SM26S Manual

Transcription

SM26S Manual
22369
2
0
10
LEVEL
8
2
10
LEVEL
0
6
10
2
10
2
6
MIX / PAN
8 6
1
CONTENTS (in order of appearance)
6
2
10
6
LEVEL
0
4
10
2
10
2
6
MIX / PAN
8 6
2
2
10
6
LEVEL
0
4
10
2
10
2
6
MIX / PAN
8 6
3
2
10
6
LEVEL
0
4
10
2
10
2
6
MIX / PAN
8 6
4
2
10
6
LEVEL
0
4
10
2
10
2
6
MIX / PAN
8 6
5
2
10
6
LEVEL
0
4
10
2
10
2
6
MIX / PAN
8 6
6
2
10
6
LEVEL
0
4
MASTER
OUTPUT
8
POWER
SPLITTER
MIXER
SM26S
SPLITTER / MIXER
4
4
Important Safety Instructions
SM26S Manual
SM26S Data Sheet
The SM26S Swiss Army Mixer
Sound System Interconnection
Schematics
Warranty
Declaration of Conformity
MASTER
INPUT
SM26S
IMPORTANT SAFETY INSTRUCTIONS
1. Read these instructions.
2. Keep these instructions.
3. Heed all warnings.
4. Follow all instructions.
5. Do not use this apparatus near water.
6. Clean only with a dry cloth.
7. Do not block any ventilation openings. Install in accordance with manufacturer’s instructions.
8. Do not install near any heat sources such as radiators, registers, stoves, or other apparatus (including amplifiers) that produce heat.
9. Do not defeat the safety purpose of the polarized or grounding-type plug. A polarized plug has two blades with one wider than the other. A
grounding-type plug has two blades and a third grounding prong. The wide blade or third prong is provided for your safety. If the provided plug
does not fit into your outlet, consult an electrician for replacement of the obsolete outlet.
10. Protect the power cord and plug from being walked on or pinched particularly at plugs, convenience receptacles, and the point where it exits from
the apparatus.
11. Only use attachments and accessories specified by Rane.
12. Use only with the cart, stand, tripod, bracket, or table specified by the manufacturer, or sold with the apparatus. When a cart is used, use caution
when moving the cart/apparatus combination to avoid injury from tip-over.
13. Unplug this apparatus during lightning storms or when unused for long periods of time.
14. Refer all servicing to qualified service personnel. Servicing is required when the apparatus has been damaged in any way, such as power supply
cord or plug is damaged, liquid has been spilled or objects have fallen into the apparatus, the apparatus has been exposed to rain or moisture, does
not operate normally, or has been dropped.
15. The plug on the power cord is the AC mains disconnect device and must remain readily operable. To completely disconnect this apparatus from
the AC mains, disconnect the power supply cord plug from the AC receptacle.
16. This apparatus shall be connected to a mains socket outlet with a protective earthing connection.
17. When permanently connected, an all-pole mains switch with a contact separation of at least 3 mm in each pole shall be incorporated in the
electrical installation of the building.
18. If rackmounting, provide adequate ventilation. Equipment may be located above or below this apparatus, but some equipment (like large power
amplifiers) may cause an unacceptable amount of hum or may generate too much heat and degrade the performance of this apparatus.
19. This apparatus may be installed in an industry standard equipment rack. Use screws through all mounting holes to provide the best support.
WARNING: To reduce the risk of fire or electric shock, do not expose this apparatus to rain or moisture. Apparatus shall not be exposed to dripping
or splashing and no objects filled with liquids, such as vases, shall be placed on the apparatus.
WARNING
CAUTION
RISK OF ELECTRIC SHOCK
DO NOT OPEN
ATTENTION: RISQUE DE CHOCS ELECTRIQUE - NE PAS OUVRIR
To reduce the risk of electrical shock, do not open the unit. No user
serviceable parts inside. Refer servicing to qualified service personnel.
The symbols shown below are internationally accepted symbols
that warn of potential hazards with electrical products.
This symbol indicates that a dangerous voltage
constituting a risk of electric shock is present
within this unit.
This symbol indicates that there are important
operating and maintenance instructions in the
literature accompanying this unit.
WARNING: This product may contain chemicals known to the State of California to cause cancer, or birth defects or other reproductive harm.
NOTE: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules.
These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses
and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio
communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful
interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct
the interference by one or more of the following measures:
• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and receiver.
• Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
• Consult the dealer or an experienced radio/TV technician for help.
CAUTION: Changes or modifications not expressly approved by Rane Corporation could void the user's authority to operate the equipment.
CAN ICES-3 (B)/NMB-3(B)
INSTRUCTIONS DE SÉCURITÉ
1. Lisez ces instructions.
2. Gardez précieusement ces instructions.
3. Respectez les avertissements.
4. Suivez toutes les instructions.
5. Ne pas utiliser près d’une source d’eau.
6. Ne nettoyer qu’avec un chiffon doux.
7. N’obstruer aucune évacuation d’air. Effectuez l’installation en suivant les instructions du fabricant.
8. Ne pas disposer près d’une source de chaleur, c-à-d tout appareil produisant de la chaleur sans exception.
9. Ne pas modifier le cordon d’alimentation. Un cordon polarisé possède 2 lames, l’une plus large que l’autre. Un cordon avec tresse de masse possède
2 lames plus une 3è pour la terre. La lame large ou la tresse de masse assurent votre sécurité. Si le cordon fourni ne correspond pas à votre prise,
contactez votre électricien.
10. Faites en sorte que le cordon ne soit pas piétiné, ni au niveau du fil, ni au niveau de ses broches, ni au niveau des connecteurs de vos appareils.
11. N’utilisez que des accessoires recommandés par Rane.
12. N’utilisez que les éléments de transport, stands, pieds ou tables spécifiés par le fabricant ou vendu avec l’appareil. Quand vous utlisez une valise de
transport, prenez soin de vous déplacer avec cet équipement avec prudence afin d’éviter tout risque de blessure.
13. Débranchez cet appareil pendant un orage ou si vous ne l’utilisez pas pendant un certain temps.
14. Adressez-vous à du personnel qualifié pour tout service après vente. Celui-ci est nécessaire dans n’importe quel cas où l’appareil est abimé : si le
cordon ou les fiches sont endommagés, si du liquide a été renversé ou si des objets sont tombés sur l’appareil, si celui-ci a été exposé à la pluie ou
l’humidité, s’il ne fonctionne pas correctement ou est tombé.
15. La fiche du cordon d’alimentation sert à brancher le courant alternatif AC et doit absolument rester accessible. Pour déconnecter totalement
l’appareil du secteur, débranchez le câble d’alimentation de la prise secteur.
16. Cet appareil doit être branché à une prise terre avec protection.
17. Quand il est branché de manière permanente, un disjoncteur tripolaire normalisé doit être incorporé dans l’installation électrique de l’immeuble.
18. En cas de montage en rack, laissez un espace suffisant pour la ventilation. Vous pouvez disposer d’autres appareils au-dessus ou en-dessous de celuici, mais certains (tels que de gros amplificateurs) peuvent provoquer un buzz ou générer trop de chaleur au risque d’endommager votre appareil et
dégrader ses performances.
19. Cet appareil peut-être installé dans une baie standard ou un chassis normalisé pour un montage en rack. Visser chaque trou de chaque oreille de
rack pour une meilleure fixation et sécurité.
ATTENTION: afin d’éviter tout risque de feu ou de choc électrique, gardez cet appareil éloigné de toute source d’humidité et d’éclaboussures quelles
qu’elles soient. L’appareil doit également être éloigné de tout objet possédant du liquide (boisson en bouteilles, vases,…).
ATTENTION
CAUTION
RISK OF ELECTRIC SHOCK
DO NOT OPEN
ATTENTION: RISQUE DE CHOCS ELECTRIQUE - NE PAS OUVRIR
Afin d’éviter tout risque de choc électrique, ne pas ouvrir l’appareil.
Aucune pièce ne peut être changée par l’utilisateur. Contactez un
SAV qualifié pour toute intervention.
Les symboles ci-dessous sont reconnus internationalement
comme prévenant tout risque électrique.
Ce symbole indique que cette unité utilise un
voltage élevé constituant un risque de choc
électrique.
Ce symbole indique la présence d’instructions
d’utilisation et de maintenance importantes dans le
document fourni.
REMARQUE: Cet équipement a été testé et approuvé conforme aux limites pour un appareil numérique de classe B, conformément au chapitre 15
des règles de la FCC. Ces limites sont établis pour fournir une protection raisonnable contre tout risque d’interférences et peuvent provoquer une
énergie de radiofréquence s'il n'est pas installé et utilisé conformément aux instructions, peut également provoquer des interférences aux niveaux
des équipements de communication. Cependant, il n'existe aucune garantie que de telles interférences ne se produiront pas dans une installation
particulière. Si cet équipement provoque des interférences en réception radio ou télévision, ceci peut être detecté en mettant l'équipement sous/hors
tension, l'utilisateur est encouragé à essayer de corriger cette interférence par une ou plusieurs des mesures suivantes:
• Réorienter ou déplacer l'antenne de réception.
• Augmenter la distance entre l'équipement et le récepteur.
• Connecter l'équipement à une sortie sur un circuit différent de celui sur lequel le récepteur est branché.
• Consulter un revendeur ou un technicien radio / TV expérimenté.
ATTENTION: Les changements ou modifications non expressément approuvés par Rane Corporation peuvent annuler l'autorité de l'utilisateur à
manipuler cet équipement et rendre ainsi nulles toutes les conditions de garantie.
CAN ICES-3 (B)/NMB-3(B)
Cartons et papier à recycler.
OPERATORS MANUAL
SM26S
SPLITTER MIXER
MASTER
INPUT
4
1
6
2
4
8
0
10
LEVEL
2
6
2
2
8 6
0
10
LEVEL
4
2
6
10
10
MIX / PAN
3
6
2
2
8 6
0
10
LEVEL
4
2
6
10
10
MIX / PAN
4
6
2
2
8 6
0
10
LEVEL
4
2
6
10
10
MIX / PAN
5
6
2
2
8 6
0
10
LEVEL
4
2
6
10
10
MIX / PAN
2
2
10
LEVEL
4
2
8 6
0
MASTER
OUTPUT
6
6
6
10
10
MIX / PAN
6
2
2
8 6
0
10
LEVEL
4
2
6
10
10
MIX / PAN
6
2
SM26S
SPLITTER
MIXER
8
0
10
LEVEL
POWER
Quick Start
SM26S Connection
Realizing that in most areas there are laws against reading owners manuals, and that reading them under the blankets at night
with a flashlight makes you feel stupid, we therefore provide this
brief, yet legal description of how to use the SM26S just in case
your batteries are low and your mother is about to come in the
room.
To achieve a quick understanding of the SM26S, think of
it as a six channel mixer with faders and pans only. Or think of
it as a 2-to-6 channel splitter with output level controls and a
mix knob (to control how much of which input goes to which
output). If you get that, you may stop here as long as you know
what a TRS plug is.
As a six channel mixer, MONO INPUT 1 through 6 may
be placed on the Right or Left bus or both, in any amount. The
respective LEVEL controls on the front serve as the mixer’s faders, the adjacent PAN controls place the channel’s signal into the
stereo field. As an effects mixer or line level expander for a larger
mixer, set up the LEVELS then adjust the PANS. The MASTER OUTPUT LEVEL adjusts the overall level of the mix at
the Master Outputs.
As a splitter, place one or both input signals into the LEFT
and/or RIGHT MASTER INs. Select the Input(s) to be placed
at each of the six MONO OUTPUTS by rotating the MIX /
PAN control to the proper position. Set the individual channel
LEVEL controls for proper output level. The MASTER INPUT
LEVEL control adjusts both Right and Left Input signal levels
together.
When connecting the SM26S to other components in your system for the first time, leave the power cord for last. This gives
you a chance to make mistakes and correct them before damage
is done to anything fragile.
As you have no doubt noticed, all Inputs and Outputs on the
SM26S’s rear panel are ¼" connectors. The Inputs and Outputs
are active balanced on Tip-Ring-Sleeve (TRS) jacks which allow
the flexibility of connecting in either a balanced or unbalanced
fashion. If unbalanced operation is your preference, the simplest
way to accomplish this is through the use of tip-sleeve ¼" connectors. The ring is not essential unless balanced operation is
required. Be aware that if you are running unbalanced and using
TRS connectors with both tip and ring, the ring and sleeve must
be shorted together. Failure to do so on the inputs results in a
gain loss of 6 dB.
Balanced operation requires that TRS plugs be used. The tip
is hot (+), the ring is return (–) and the sleeve is ground. RaneNote, “Sound System Interconnection” (included here) contains
some great pictures to aid your interconnect ventures.
WEAR PARTS: This product contains no wear parts.
Manual-1
Front Panel Description
MASTER
INPUT
4
1
6
2
4
8
0
10
2
6
2
2
8 6
0
10
4
2
6
10
10
LEVEL
LEVEL
MIX / PAN
1
2 3
3
6
2
2
8 6
0
10
LEVEL
4
2
6
10
10
MIX / PAN
4
6
2
2
8 6
0
10
LEVEL
4
2
6
10
10
MIX / PAN
5
6
2
2
8 6
0
10
LEVEL
4
2
6
10
10
MIX / PAN
2
2
10
LEVEL
4
2
8 6
0
MASTER
OUTPUT
6
6
6
10
10
MIX / PAN
6
2
2
8 6
0
10
LEVEL
4
2
6
10
10
MIX / PAN
6
2
SM26S
SPLITTER
MIXER
8
0
10
LEVEL
POWER
4 5
1 MASTER INPUT LEVEL sets the gain of the Left & Right Master Input stages, with a range of Off to +12 dB. In the splitting
mode, this controls the Level of all Mono channel Outputs at once (i.e., those which do not have a separate input).
2 Mono Input LEVEL controls the Level of signal through each particular channel. When fed from the MONO INPUT jack,
each stage has a gain range from Off to +12 dB minimum, allowing level matching of -10 dBV equipment to +4 dBu gear. When
fed via the LEFT & RIGHT MASTER IN, these LEVEL controls automatically limit to a maximum of unity gain to accommodate the +12 dB available from the Left & Right Input gain stages.
3 MIX / PAN serves two different functions:
MIX: When used as a SPLITTER, this controls the mix of Left and Right Master Input program to each channel’s MONO
OUT.
PAN: When used as a MIXER, this control pans the Mono channel Input between the LEFT and RIGHT MIX OUTPUTS.
4 MASTER OUTPUT LEVEL controls the gain of the output stages and the amount of signal at the MIX OUTPUT jacks. It
does not affect the level of any of the six MONO OUTPUTs. This allows an increase in headroom to eliminate overloading due to
excessive combined signal from one or more Inputs. Range of gain is from Off to 0 dB (unity). Refer to the block diagram below.
5 POWER indicator: When this yellow LED is lit, the SM26S is ready to go (when it’s off, it’s not).
Manual-2
Rear Panel Description
SM26S
100-240 V
50/60 Hz 7 WATTS
LEFT
COMMERCIAL AUDIO
EQUIPMENT 24TJ
6
R
LEFT
This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions:
(1) this device may not cause harmful interference, and (2) this device must accept any interference
received, including interference that may cause undesired operation. CAN ICES-3 (B)/NMB-3(B)
5
4
3
2
All Inputs and Outputs are Balanced: Tip = positive (+), Ring = Negative (–), Sleeve = Chassis Ground.
All audio jacks are Class 2 wiring.
1
6
RIGHT
5
4
3
2
1
RIGHT
RANE CORPORATION
MIX OUTPUT
MONO OUTPUTS
EXPAND OUT
MASTER IN
MONO INPUTS
6
5
3
4
1
2
1 MASTER IN are balanced Tip-Ring-Sleeve (TRS) ¼" Master Inputs. These Inputs feed all six MONO OUTs when all MONO
INs are not used. Connecting to individual MONO INs disconnects that channel from these Inputs (refer to the Block Diagram).
For unbalanced operation use a standard mono ¼" plug; for balanced operation use a TRS (stereo) ¼" plug wired as follows:
TIP is signal + (connect to Pin 2 on a 3-pin connector).
RING is signal – (pin 3 in a 3-pin connector).
SLEEVE is chassis ground.
2 MONO INPUTS are TRS ¼" jacks which accept either balanced or unbalanced mono signals. These are switching jacks which
automatically bypass the MASTER IN jacks whenever a plug is inserted (see the Block Diagram). Same wiring conventions as in
1 above.
3 MONO OUTPUTS are ¼" TRS jacks that deliver either an unbalanced output (use TS plugs), or a balanced output (use TRS
plugs). Follow wiring conventions as in 1 above.
4 EXPAND OUTS are ¼" TRS jacks connected in parallel with the MASTER IN jacks, allowing two or more SM26Ss to be
daisychained for multiple splitting. Simply connect the EXPAND OUT to the MASTER IN of another SM26S; there is no limit
to the number of expansions possible with the SM26S.
NOTE: These Expand Outputs are not buffered from the Master Inputs. Therefore it is not possible to mix both balanced and
unbalanced lines in the same channel between several units: once the ring and sleeve are shorted anywhere in the chain (by using a
mono plug) the entire line becomes unbalanced.
5 MIX OUTPUTS are balanced TRS ¼" outputs controlled by the MASTER OUTPUT LEVEL control. They are fed either by
the MASTER IN or by any of the six MONO INPUTS, or a combination of both (see The Swiss Army Mixer RaneNote). Follow
wiring conventions as in 1 above.
6 Universal Voltage Input: via a miniature IEC 60320 C6 appliance inlet. This mates with an IEC 60320 C5 line cord (USA
domestic). Do not lift the ground connection!
Manual-3
Operating Instructions
Since numerous applications exist for the SM26S, no single
set of operational procedures control its use. The SM26S Swiss
Army Mixer RaneNote (included) explores the many configurations of the SM26S in depth, and you should peruse it for
applications information.
SHIP POSITION: SEND CHANNEL OUTPUT TO THE MIX BUS
CHANGE JUMPER TO DISCONNECT AND ONLY ROUTE TO THE MONO OUT
Internal Jumper Options
There exist within the SM26S some signal routing options,
requiring removal of the top cover to move some jumpers.
This must only be done with the power off by qualified service
personnel.
If an SM26S needs to have an additional set of independent outputs, as in a 2x4 stereo distribution amplifier (see
Swiss Army Mixer, Figure 10), the LEFT and RIGHT MIX
OUTPUTS can be used in addition to the 6 MONO OUTS.
Normally, the LEFT and RIGHT MIX OUTPUTS produce
the sum mix of all 6 LEVEL and PAN controls. To break any
channel away from the Mix Output bus, internal jumpers
have been provided. These are located behind the MIX/PAN
controls for each channel. J3 connects MONO OUT 1 to the
mix bus. J6 connects MONO OUT 2, J9 connects MONO
OUT 3, and so on — see the board layout.
©Rane Corporation 10802 47th Ave. W., Mukilteo WA 98275-5000 USA TEL 425-355-6000 FAX 425-347-7757 WEB rane.com
Manual-4
DATA SHEET
SM26S
SPLITTER MIXER
General Description
The Rane Model SM26S Splitter Mixer is one of the most useful,
yet unusual audio products available. In its most basic configuration, it is a six-to-two line level mixer. It will accept six balanced
or unbalanced line level inputs which are applied to six Level and
Pan controls. An additional stereo Master Input allows a total of
eight inputs. The result of the mix is sent to an overall Master
Output Level control and appears at the Left and Right Outputs
on the rear. In its splitter mode, the SM26S can take one or two
line level inputs and split these to any of the six Mono Outputs
on the rear. The Mix/Pan controls in this mode control the level
from each of the two input buses to be applied to each Output.
Internal header blocks allow the Mix Outputs to become an
independent stereo out, allowing a total of eight outputs. The
SM26S may also be used as a six input, six output buffer amplifier in which case signal applied to Input 1 is delivered to Output
1, and so on.
The SM26S may also be used in a combination of modes at once.
For instance, Inputs 1 through 3 may be mixed to the left and/
or right output buses while at the same time Outputs 4 and 5 are
delivering signal originally applied to the Left and Right Master
Inputs while at the same time Output 6 is being driven from
Input 6 in the straight through mode.
The front of the SM26S comprises a Master Input Level
control, six Channel Level controls, six Mix/Pan controls and a
Master Output Level control. The rear of the SM26S provides
two Master Left and Right Inputs, six Mono Inputs, six Mono
Outputs and two Master Left and Right Mix Outputs. All Inputs
and Outputs on the SM26S are ¼" TRS active balanced.
See the RaneNote, “The SM26S Swiss Army Mixer” for additional application information, available from our website.
Features
Applications
•
•
•
•
•
•
•
–10 dBV to +4 dBu Shifter
+4 dBu to –10 dBV Shifter
6 Balanced Mono Inputs, 6 Balanced Mono Outputs
2 Main Balanced Inputs, 2 Main Balanced Outputs
6 Input Level Controls and 6 Mix/Pan Controls
Master Input and Output Level Controls
Internal Universal Power Supply (100-230 VAC)
•
•
•
•
•
•
6 Mono Inputs, Stereo Output Line Mixer
4 Stereo Inputs, Stereo Output Line Mixer
Stereo Input, 6 Mono Output Line Splitter
1 Stereo Input, 4 Stereo Output Splitter
6-In, 6-Out Booster Amplifier
Configurable to 8 Outputs
Data Sheet-1
SM26S
SPLITTER MIXER
Features and Specifications
Parameter
Specification
Limit
Units
Conditions/Comments
Inputs: Type
Active Balanced
..........Connectors
¼" TRS
..........Impedance
20k
1%
Ω
..........Maximum Level
22
1
dBu
Outputs: Type
Active Balanced
..........Connectors
¼" TRS
..........Impedance
125
typ
Ω
1 kHz
..........Maximum Level
26
1
dBu
10 kΩ or greater
Overall Gain Range
Off to +12
-0/+6
dB
Any Input to any Output
RFI Filters
Yes
5%
Frequency Response
10-40 kHz
+0/-3
dB
THD+Noise
0.008
.002
%
+4 dBu, 20-20 kHz unity gain
IM Distortion (SMPTE)
0.009
.002
%
60 Hz /7 kHz, 4:1, +4 dBu unity gain
Tip=(+), Ring=(–), Sleeve=GND
Signal-to-Noise Ratio
re +4 dBu, 20 kHz noise bandwidth
120
2
dB
Mono Outputs, unity gain
98
2
dB
Mix Outputs, unity gain
..........L-R Panning
60 (1 kHz)
2
dB
Any Input to Mix Outs
..........Channel-Channel
75 (1 kHz)
2
dB
Any Input to Mix Outs
Mean Time Between Failure
35,500 hours
h
Mil-Hdbk-217D, Section V
Unit: Maximum Power
7
W
..........Universal Line Voltage
100 to 240
..........Conformity
CE, FCC, CULUS
..........Construction
All Steel
19" 1U Rackmount
..........Size
1.75" H x 19" W x 5.3" D
(4.4 cm x 48.3 cm x 13.5 cm)
..........Weight
5 lb
(2.3 kg)
Shipping: Size
4.25" x 20.3" x 13.75"
(11 cm x 52 cm x 35 cm)
..........Weight
9 lb
(4.1 kg)
Note: 0 dBu=0.775 Vrms
Unity Gain = Master Levels Set to ~ “7” Position
Crosstalk
Data Sheet-2
10%
VAC
50/60 Hz
SM26S
SPLITTER MIXER
Block Diagram
Application Information
Aptly nicknamed the “Swiss Army Mixer”, the SM26S is an
extremely versatile single rack-space tool providing a number of
different functions to solve a broad spectrum of line-level signal
routing problems. Whether the need is for line mixing, line
distribution or line matching/amplification, the SM26S easily
performs these tasks, along with additional features for even more
flexibility.
One of the most popular uses is line-level mixing for keyboards, drum machines, and effects. Expanding existing console
limitations is simple. Whenever a mono or stereo sub-mix is
desired, the SM26S comes to the rescue. Up to three stereo, or six
mono sources easily mix together, with panning ability on every
input. Many musical instrument performers find the SM26S
indispensable for combining various effects and expanding the
available loops on their signal processors.
The SM26S capabilities also include a wide variety of functions such as live recording splitting, -10 dBV to +4 dBm level
matching, intercom splitting, line boosting, hotel and club zone
management, restaurant paging systems, adding additional monitor buses for studio or stage use, and many more custom applications. Please consult the RaneNote “The SM26S Swiss Army
Mixer” for in-depth applications.
The SM26S provides full expansion capabilities for all applications. Simple ¼" TRS connectors allow expansion using patch
cords. Using these provisions, an unlimited number of lines may
be mixed or split upon demand. For example, three units create
either an 18 input mixer or an 18 output splitter, or a combination of both.
Data Sheet-3
SM26S
SPLITTER MIXER
Rear Panel
Architectural Specifications
The splitter mixer unit shall have six (6) mono inputs, six (6)
mono outputs, two (2) master inputs, and two (2) master outputs. The unit shall be capable of mixing or splitting any inputs
to any outputs simultaneously. Each mono input shall have a level
control with a range of off to +12 dB gain. Separate +12 dB gain
Master Input and Output Level controls shall be provided.
Complete expansion capabilities shall be provided to allow
any number of similar units to be coupled together.
A combination Mix or Pan control shall be provided on each
of the six (6) mono channels to allow any output to be a mix of
the two master inputs, or to allow any mono input to be panned
between the two master outputs.
The inputs and outputs shall be active balanced designs terminated with ¼" TRS (tip-ring-sleeve) connectors. RFI filters shall
be provided. Ultrasonic filters shall be built-in.
The unit shall be capable of operation by means of its own
built-in universal power supply operating at 100-240 VAC and
meet CE requirements (pending). The unit shall be UL and cUL
listed (pending). The unit shall be entirely constructed from coldrolled steel.
The unit shall be a Rane Corporation SM26S.
©Rane Corporation 10802 47th Ave. W., Mukilteo WA 98275-5000 USA TEL 425-355-6000 FAX 425-347-7757 WEB rane.com
Data Sheet-4
All features & specifications subject to change without notice. 9-2015
RaneNote
SM26S SWISS ARMY MIXER
The SM26S Swiss Army Mixer
• 6 In, 2 Out Mixer
• 2 In, 6 Out Splitter
• 6 In, 6 Out Buffer Amplifier
• 4 Channel Stereo Splitter
• Other Applications
Introduction
Everyone needs a line level mixer. Even my mother. It
has to be small, and cheap, and versatile. It has to be
able to mix split, distribute, level match, amplify, at‑
tenuate and pan—all without adding any distortion or
noise whatsoever. The mind reels...
And recovers, and discovers the Rane SM26S Split‑
ter Mixer. It is small (1 rack space), extremely versatile,
and affordable. It is a 6 in / 2 out mixer, a 2 in / 6 out
splitter/distribution amplifier, and a 6 in / 6 out buffer
amplifier. It has 12 dB of gain and better than 80 dB
of attenuation. The distortion products are less than
.008% and the noise floor is a trifle 35 microvolts.
Inside this RaneNote is found a gruelingly complete
description of the innards of an SM26S and a patheti‑
cally skimpy introduction to the many possible ap‑
plications of same. Such is my belief that you are the
best judge of how to apply the SM26S once you really
understand its workings.
Dennis Bohn
Rane Corporation
RaneNote 108
© 1983, 2007 Rane Corporation
Swiss Army Mixer-1
Block Diagram
A complete block diagram of the SM26S appears as
Figure 1. (Get your eyeglasses, you may need them.)
Stereo input pairs are accommodated by the individual
LEFT and RIGHT INPUT jacks. Expansion or “daisy
chaining” is possible through the use of the parallel
EXPAND OUT jacks. A dual ganged MASTER INPUT
LEVEL control sets the gain from off to +12 dB for both
Inputs.
From here, the Master Inputs feed a left and right
mixing bus to each of the six MIX pots, as well as going
straight through to the MASTER OUTPUT LEVEL
control stage which feeds the Left and Right Mix
Outputs. The Output from each of the Mix pots feeds
the individual Mono Channel Level stages through a
switching contact associated with the MONO IN jack.
(The jacks are drawn in their open, i.e., unused state.
Inserting a plug into the MONO IN jack causes the
auxiliary switch to change position.) The combined left
and right signals go to each of the channel Outputs.
Individual mono inputs enter through the MONO
IN jacks, through the (now closed) auxiliary switch to
the +12dB gain stage where it feeds the MONO OUT
jack. The PAN pot splits the signal into two signals that
feed the LEFT and RIGHT MIX OUTPUTs via the
Master Outputs.
It’s really quite simple. Now let’s look at specific con‑
figurations, leaving out the unused circuitry.
Figure 1. SM26S Complete Block Diagram
Swiss Army Mixer-2
LEFT
EXPAND
OUTPUT
LEFT
MASTER
INPUT
LEFT MIX
OUTPUT
MASTER
INPUT
LEVEL
RIGHT
EXPAND
OUTPUT
MASTER
OUTPUT
LEVEL
RIGHT
MASTER
INPUT
RIGHT MIX
OUTPUT
6+ In / 2 Out Mixer
Figure 2 diagrams the SM26S signal path when configured as a 6+
In/2 Out mixer. The individual Inputs are connected to each of the
six MONO IN jacks and the combined Outputs are taken from the
LEFT AND RIGHT MIX OUTPUT Jacks. The “plus” comes from
the fact that the LEFT and RIGHT INPUTS also connect to the
LEFT and RIGHT MIX OUTPUTS. There is no pan capability on
these two Inputs, but each of them does sum with the 6 MONO
INs to produce a 6 plus LEFT to the LEFT OUTPUT and a 6 plus
RIGHT to the RIGHT OUTPUT option if so desired.
MONO
OUT 1
MIX 1
CH. 1 LEVEL
MONO
OUT 2
MIX 2
CH. 2 LEVEL
MONO
OUT 3
MIX 3
CH. 3 LEVEL
LEFT
EXPAND
OUTPUT
MONO
OUT 4
LEFT
MASTER
INPUT
RIGHT
EXPAND
OUTPUT
LEFT MIX
OUTPUT
MASTER
INPUT
LEVEL
CH. 4 LEVEL
MONO
OUT 5
MASTER
OUTPUT
LEVEL
RIGHT
MASTER
INPUT
MIX 4
MIX 5
CH. 5 LEVEL
MONO
OUT 6
RIGHT MIX
OUTPUT
MIX 6
CH. 6 LEVEL
Figure 3. 2 In / 6+ Out Splitter / Distribution Amp
PAN 1
MONO
INPUT 1
CH. 1 LEVEL
PAN 2
MONO
INPUT 2
CH. 2 LEVEL
PAN 3
MONO
INPUT 3
CH. 3 LEVEL
PAN 4
MONO
INPUT 4
CH. 4 LEVEL
PAN 5
MONO
INPUT 5
2 In / 6+ Out Splitter / Distribution Amplifier
Figure 3 shows how the SM26S can be used in the ex‑
act opposite mode as described above. When wired per
Figure 3, the SM26S becomes a 2 In / 6+ Out Splitter/
Distribution Amp. The master stereo signal is con‑
nected to the LEFT and RIGHT INPUT jacks and is
summed via the six MIX pots to each of the MONO
OUTPUTS. The “plus” is that the stereo bus is also
coupled directly through to the LEFT and RIGHT MIX
OUTPUTS. This allows signal translation from ‑10
dBV to +4 dBm or other level related conditioning to
the master stereo bus before feeding other equipment.
CH. 5 LEVEL
PAN 6
MONO
INPUT 6
CH. 6 LEVEL
Figure 2. 6+ In / 2 Out Mixer Configuration
Swiss Army Mixer-3
MONO
INPUT 1
RFI
FILTER
MONO
OUT 1
0 dB
CH. 1 LEVEL
6 In / 6 Out Buffer Amplifier
Figure 4 shows how the SM26S can be used
as a “straight through” line buffer amplifier.
Inputs are brought into the MONO IN jacks
and exit from the MONO OUT jacks. Each
channel has a separate +12dB gain stage with
LEVEL control.
NOTE: One additional channel can be
gained by rotating all the PAN pots fully CW
and using the LEFT INPUT and LEFT MIX
OUTPUT (or rotate tully CCW and use the
RIGHT IN and OUT combination).
MONO
INPUT 2
RFI
FILTER
MONO
OUT 2
0 dB
CH. 2 LEVEL
MONO
INPUT 3
RFI
FILTER
MONO
OUT 3
0 dB
CH. 3 LEVEL
MONO
INPUT 4
RFI
FILTER
MONO
OUT 4
0 dB
CH. 4 LEVEL
MONO
INPUT 5
RFI
FILTER
MONO
OUT 5
0 dB
CH. 5 LEVEL
MONO
INPUT 6
RFI
FILTER
MONO
OUT 6
0 dB
CH. 6 LEVEL
Figure 4. 6 In/6 Out Buffer Amplifier
Swiss Army Mixer-4
LEFT
BUS
RIGHT
BUS
RIGHT INPUT
EXPAND OUT
RIGHT INPUT
EXPAND OUT
2x6
SM26S
1
2
3
4
5
6
Expansion
Expanding the input and output capacity of the SM26S
Splitter Mixer is quite easy. Figure 5 shows the proce‑
dure for splitter mode expansion. The Left and Right
Input buses are “daisy chained” using the EXPAND
OUT jacks as shown, and the Outputs are taken di‑
rectly from each SM26S's MONO OUTS.
Mixer expansion is the reverse procedure and ap‑
pears as Figure 6. Inputs are brought into each of the
SM26S’s while their respective LEFT and RIGHT MIX
OUTPUTS are used to cascade the chain by con‑
necting to the LEFT and RIGHT INPUTS of the next
SM26S, and so on.
2 x 12
RIGHT INPUT
EXPAND OUT
RIGHT INPUT
EXPAND OUT
2 x 18
SM26S
1
2
3
4
5
6
RIGHT INPUT
EXPAND OUT
RIGHT INPUT
EXPAND OUT
SM26S
1
2
3
4
5
6
TO ANOTHER SM26S...
Figure 5. Splitter Expansion
RIGHT INPUT
LEFT INPUT
1
2
3
4
5
6
SM26S
LEFT MIX OUTPUT
RIGHT MIX OUTPUT
6x2
RIGHT INPUT
LEFT INPUT
1
2
3
4
5
6
SM26S
LEFT MIX OUTPUT
RIGHT MIX OUTPUT
12 x 2
RIGHT INPUT
LEFT INPUT
1
2
3
4
5
6
Figure 6. Mixer Expansion
SM26S
18 x 2
LEFT MIX OUTPUT
RIGHT MIX OUTPUT TO ANOTHER SM26S...
Swiss Army Mixer-5
Applications
The SM26S is unusually versatile in its applications.
With the capability to mix 6 Mono Inputs down to one
stereo pair, or split one stereo pair into 6 separate Out‑
puts. or condition 6 Inputs by adding gain or attenua‑
tion—all of this either balanced or unbalanced and able
to drive 600 Ω lines, makes the SM26S truly a “Swiss
Army Mixer”. Further, any combination of the above
can occur at the same time, in the same unit.
1 In / 3 Out +
3 In / 3 Out Combination
For instance. you can split one signal into three sepa‑
rate Outputs with individual LEVEL controls and
use the remaining three MONO INS and OUTS as
buffer/line driving amps. creating a 1‑to‑3 / 3‑to‑3
combination.
Zone Amplifier Level Controls
Adding individual remote level controls to the MA 3
Multichannel Amplifier is easy with the SM26S as dia‑
grammed in Figure 7. The mono signal is applied to the
LEFT INPUT jack and the 6 balanced MONO OUTS
are connected to the balanced inputs of the MA 3. Ro‑
tating all MIX pots fully CCW routes the Input signal
to each of the MONO OUTS. Each individual Output
is adjusted by its respective channel LEVEL control.
If separate sources are connected to the LEFT and
RIGHT INPUT jacks then the individual MIX pots
will determine which source (or combination of both)
is presented to each of the MONO OUTS. Full CCW
rotation gives Left only; full CW rotation gives Right
only; and the middle position gives equal amounts of
Left plus Right.
6 In / 6+2 Out
Another interesting combination is to use the SM26S
as a 6 In / 6 Out level translation amplifier (infinite cut
to +12 dB boost) and also mix the 6 Mono Inputs down
to one stereo pair with the PAN pots. The stereo Out‑
put appears at the LEFT and RIGHT MIX OUTPUT
jacks.
6+2 In / 2 Out
Or bring 6 Mono and 1 Stereo pair into the
SM26S and add the 6 MONO INs to the stereo pair via
the PAN pots. You now have a 6+2 In / 2 Out situation
with the 6 Mono Inputs still available as 6 buffered
Outputs if needed.
LEFT INPUT
SM26S
1
1
2
2
3
3
4
4
5
5
6
6
MA3
MA3
Figure 7. Level Controls for two MA 3 Amplifiers
Stereo Headphone Mixer
Figure 8 shows how the SM26S can be used as a
6 In / 2 Out stereo mixer driving the HC 6 Headphone
Console. Six Mono Inputs are brought into the SM26S
where they are mixed together via the PAN pots to
create a stereo output signal at the LEFT and RIGHT
MIX OUTPUT jacks. These lines are connected to the
MASTER LEFT and RIGHT INPUT jacks of the HC 6
where they drive the six stereo headphone amplifiers.
LEFT MIX OUTPUT
RIGHT MIX OUTPUT
1
2
3
4
SM26S
LEFT INPUT
RIGHT INPUT
HC6S
1
HEADPHONE 1
2
3
HEADPHONE 2
HEADPHONE 3
4
5
5
6
6
HEADPHONE 4
HEADPHONE 5
Figure 8. Stereo Headphone Mixer
Swiss Army Mixer-6
HEADPHONE 6
1
LEFT MIX OUTPUT
RIGHT MIX OUTPUT
LEFT INPUT
RIGHT INPUT
2
6-to-1-to-6 Mixer Splitter
3
SM26S
Figure 9 shows how to use two SM26S’s to
4
create a 6-to-1 mix then a 1-to-6 splitter,
5
6
to drive the six channels of two MA 3 am‑
plifiers. In just six rack spaces, this con‑
figuration creates a complete six-channel
mixer zone amplifier system.
The controls of the first SM26S are used to condition
and mix the six Mono Input signals while the controls
of the second SM26S are used to set the individual
Levels of the six amplifiers.
4-Channel Stereo Splitter
Don’t get into the mind trap of thinking of the SM26S
as only a mono splitter mixer. It can function equally
well as a stereo splitter mixer. Figure 10 shows how
to configure the SM26S as a 4-channel stereo splitter.
The stereo Input pair is brought into the Left and Right
INPUT jacks and then routed via the MIX pots to all of
the Outputs. By setting Channels 1, 3 and 5 for full Left
mix and channels 2, 4 and 6 for full Right mix, you split
the incoming signal into 3 stereo output pairs available
from OUTS 1 & 2, 3 & 4, and 5 & 6 respectively. The
4th stereo Output pair is taken from the Left and Right
MIX OUTPUT jacks as shown. (Note: use of the 4th
independent stereo output requires an internal jumper
modification.)
Stereo mixing is done in the exact opposite man‑
ner. Up to 4 stereo pairs are brought into all Inputs
by connecting one pair to the Left and Right INPUT
jacks and the three remaining “lefts” to Channels 1,
3 and 5, and the “rights” to Channels 2, 4 and 6. Now
by rotating all odd PAN pots fully CCW(Left) and all
even PANs fully CW(Right), you have mixed all 4 pairs
down to 1 master pair available at the Left and Right
MIX OUTPUTs.
SM26S
1
1
2
2
3
3
4
4
5
5
6
6
MA3
MA3
Figure 9. Mixer Splitter
STEREO
INPUT
PAIR
LEFT INPUT
RIGHT INPUT
1
2
3
4
SM26S
5
6
LEFT OUTPUT
RIGHT OUTPUT
STEREO PAIR 1
STEREO PAIR 2
STEREO PAIR 3
STEREO PAIR 4
Figure 10. Four Channel Stereo Splitter
GUITAR AMP
FROM
GUITAR
LOOP SEND
LOOP RETURN
Guitar Racks
Figures 11-13 show three possible ways to connect a
guitar amp to multiple effects. Figure 11 involves buy‑
ing or building a cable that parallels all of the inputs
of the effects so one loop output drives them all. This
works and should cause no great difficulty if the output
impedance of the amplifier loop is low. Outputs of 1k
ohms or less should be able to drive as many effects de‑
vices as you would ever want. A second amplifier could
be used from the other Mix Output of the SM26S for
stereo.
MONO IN
L
1
R
2
L
3
R
4
L
5
R
6
EFFECT 1
MONO IN
EFFECT 2
MONO IN
EFFECT 3
SM26S
Figure 11. Guitar Effects Mixer
Swiss Army Mixer-7
Many effects have mono inputs and stereo outputs.
In this case, connect the left and right outputs of Effect
1 to MONO IN CHANNELS 1 and 2 of the SM26S
respectively. Rotate the MIX/PAN control of Channel
1 all the way to the Left and the MIX/PAN of Chan‑
nel 2 all the way to the Right. This preserves the mix of
the effects’ stereo output and passes it to the LEFT &
RIGHT MIX OUTPUTs of the SM26S. Continue with
Channels 3 & 4 for the second effect and Channels 5 &
6 for the last effect. Set the Channel LEVEL pairs to the
same levels to preserve the intended mix of the stereo
effect.
The best way, shown in figure 12, uses one SM26S as
a splitter to actively split the signal into as many as six
separate feeds (or three stereo) for the effects inputs.
A second SM26S mixes all of the effects outputs back
together.
Now here's a way to split and mix with one SM26S,
shown in Figure 13. From the loop output going to
the LEFT INPUT, Channels 1,2 and 3 will act as the
splitter, with their pan controls all the way to the left
bus. Since the MONO IN jacks know that an individual
Input overrides the master Input…Channels 4,5 and
6 will act as the mixer, with their pan controls all the
way to the right. The RIGHT MIX OUTPUT returns
signal to the amplifier. Cool!
DJ Effects Mixer
DJ mixers have stereo sends and returns, but it’s just as
easy to use the SM26S to combine 3 stereo effects. The
concept is the same as the Guitar Rack in Figure 11, but
in stereo. See Figure 14.
And More
The range of applications of the Model SM26S Split‑
ter Mixer is staggering and have been barely touched
in this RaneNote. From simple sub-mixing to complex
split-mix combinations, to individual equipment signal
conditioning, to line splitting, to your unique applica‑
tion, the list of uses for the SM26S goes on and on.
Experiment and have fun!
FROM
GUITAR
GUITAR AMP
LOOP SEND
LOOP RETURN
1
SM26S
1
EFFECT 1
2
2
3
3
EFFECT 2
4
LEFT OUTPUT
SM26S
4
5
6
RIGHT OUTPUT
5
EFFECT 3
6
LOOP RETURN
GUITAR AMP
Figure 12. Ultimate Guitar Effects Splitter/Mixer
FROM
GUITAR
GUITAR AMP
LOOP SEND
LOOP RETURN
LEFT INPUT
1
(1,2,3 PAN LEFT)
2
EFFECT 1
3
EFFECT 2
SM26S
4
5
EFFECT 3
(4,5,6 PAN RIGHT)
6
RIGHT OUTPUT
Figure 13. Mono Guitar Effects Splitter/Mixer
DJ MIXER
EFFECTS LOOP SEND
L R
L
EFFECTS LOOP RETURN
L R
L
1
PAN L
R
2 PAN R
L
3
R
4 PAN R
L
5
PAN L
L
R
6 PAN R
R
EFFECT 1
R
L
EFFECT 2
R
L
R
EFFECT 3
PAN L
SM26S
Figure 14. DJ Mixer Effects Loop Mixer
©Rane Corporation 10802 47th Ave. W., Mukilteo WA 98275-5098 USA TEL 425-355-6000 FAX 425-347-7757 WEB www.rane.com
Swiss Army Mixer-8
DOC 103062
RaneNote
SOUND SYSTEM INTERCONNECTION
Sound System
Interconnection
• Cause & prevention of ground loops
• Interfacing balanced & unbalanced
• Proper pin connections and wiring
• Chassis ground vs. signal ground
• Ground lift switches
Introduction
This note, originally written in 1985, continues to be one
of our most useful references. It’s popularity stems from
the continual and perpetual difficulty of hooking up audio
equipment without suffering through all sorts of bizarre
noises, hums, buzzes, whistles, etc.— not to mention the
extreme financial, physical and psychological price. As technology progresses it is inevitable that electronic equipment
and its wiring should be subject to constant improvement.
Many things have improved in the audio industry since
1985, but unfortunately wiring isn’t one of them. However,
finally the Audio Engineering Society (AES) has issued a
standards document for interconnection of pro audio equipment. It is AES48, titled “AES48-2005: AES standard on
interconnections —Grounding and EMC practices — Shields
of connectors in audio equipment containing active circuitry.”
Rane’s policy is to accommodate rather than dictate.
However, this document contains suggestions for external
wiring changes that should ideally only be implemented by
trained technical personnel. Safety regulations require that
all original grounding means provided from the factory be
left intact for safe operation. No guarantee of responsibility
for incidental or consequential damages can be provided. (In
other words, don’t modify cables, or try your own version of
grounding unless you really understand exactly what type of
output and input you have to connect.)
Rane Technical Staff
RaneNote 110
© 1985, 1995, 2006, 2007, 2011, 2015 Rane Corporation
Interconnection-1
Ground Loops
Almost all cases of noise can be traced directly to ground
loops, grounding or lack thereof. It is important to understand the mechanism that causes grounding noise in order
to effectively eliminate it. Each component of a sound
system produces its own ground internally. This ground is
usually called the audio signal ground. Connecting devices
together with the interconnecting cables can tie the signal
grounds of the two units together in one place through
the conductors in the cable. Ground loops occur when the
grounds of the two units are also tied together in another
place: via the third wire in the line cord, by tying the metal
chassis together through the rack rails, etc. These situations
create a circuit through which current may flow in a closed
“loop” from one unit’s ground out to a second unit and back
to the first. It is not simply the presence of this current that
creates the hum—it is when this current flows through a
unit’s audio signal ground that creates the hum. In fact, even
without a ground loop, a little noise current always flows
through every interconnecting cable (i.e., it is impossible to
eliminate these currents entirely). The mere presence of this
ground loop current is no cause for alarm if your system
uses properly implemented and completely balanced interconnects, which are excellent at rejecting ground loop and
other noise currents. Balanced interconnect was developed
to be immune to these noise currents, which can never be
entirely eliminated. What makes a ground loop current annoying is when the audio signal is affected. Unfortunately,
many manufacturers of balanced audio equipment design
the internal grounding system improperly, thus creating balanced equipment that is not immune to the cabling’s noise
currents. This is one reason for the bad reputation sometimes given to balanced interconnect.
A second reason for balanced interconnect’s bad reputation comes from those who think connecting unbalanced
equipment into “superior” balanced equipment should
improve things. Sorry. Balanced interconnect is not compat-
ible with unbalanced. The small physical nature and short
cable runs of completely unbalanced systems (home audio)
also contain these ground loop noise currents. However, the
currents in unbalanced systems never get large enough to
affect the audio to the point where it is a nuisance. Mixing
balanced and unbalanced equipment, however, is an entirely
different story, since balanced and unbalanced interconnect
are truly not compatible. The rest of this note shows several
recommended implementations for all of these interconnection schemes.
The potential or voltage which pushes these noise currents through the circuit is developed between the independent grounds of the two or more units in the system. The
impedance of this circuit is low, and even though the voltage
is low, the current is high, thanks to Mr. Ohm, without
whose help we wouldn’t have these problems. It would take
a very high resolution ohm meter to measure the impedance
of the steel chassis or the rack rails. We’re talking thousandths of an ohm. So trying to measure this stuff won’t
necessarily help you. We just thought we’d warn you.
The Absolute Best Right Way To Do It
The method specified by AES48 is to use balanced lines and
tie the cable shield to the metal chassis (right where it enters
the chassis) at both ends of the cable.
A balanced line requires three separate conductors, two
of which are signal (+ and –) and one shield (see Figure 1a).
The shield serves to guard the sensitive audio lines from
interference. Only by using balanced line interconnects can
you guarantee (yes, guarantee) hum-free results. Always use
twisted pair cable. Chassis tying the shield at each end also
guarantees the best possible protection from RFI [radio frequency interference] and other noises [neon signs, lighting
dimmers].
Neil Muncy1, an electroacoustic consultant and seasoned
veteran of years of successful system design, chairs the AES
BALANCED OUTPUTS
+
–
BALANCED INPUTS
RED
BLACK
SHIELD
+
RED
BLACK
SHIELD
2-CONDUCTOR SHIELDED CABLE
–
G
G
MALE
2
3
1
T
R
S
CHASSIS
GROUND
Interconnection-2
FEMALE
RED
2
BLACK
C 3
SHIELD
1
RED
BLACK
SHIELD
2-CONDUCTOR SHIELDED CABLE
RED
BLACK
SHIELD
2-CONDUCTOR SHIELDED CABLE
RED
BLACK
SHIELD
Figure 1a. The right way to do it.
MALE
2
3
1
FEMALE
2
C 3
1
T
R
S
CHASSIS SIGNAL
GROUND GROUND
Standards Committee (SC-05-05) working on this subject.
He tirelessly tours the world giving seminars and dispensing information on how to successfully hook-up pro audio
equipment2. He makes the simple point that it is absurd that
you cannot go out and buy pro audio equipment from several different manufacturers, buy standard off-the-shelf cable
assemblies, come home, hook it all up and have it work hum
and noise free. Plug and play. Sadly, almost never is this the
case, despite the science and rules of noise-free interconnect
known and documented for over 60 years (see References for
complete information).
It all boils down to using balanced lines, only balanced
lines, and nothing but balanced lines. This is why they were
developed. Further, that you tie the shield to the chassis, at
the point it enters the chassis, and at both ends of the cable
(more on ‘both ends’ later).
Since standard XLR cables come with their shields tied to
pin 1 at each end (the shells are not tied, nor need be), this
means equipment using 3-pin, XLR-type connectors must
tie pin 1 to the chassis (usually called chassis ground) — not
the audio signal ground as is most common.
Not using signal ground is the most radical departure
from common pro-audio practice. Not that there is any argument about its validity. There isn’t. This is the right way
to do it. So why doesn’t audio equipment come wired this
way? Well, some does, and since 1993, more of it does. That’s
when Rane started manufacturing some of its products with
balanced inputs and outputs tying pin 1 to chassis. So why
doesn’t everyone do it this way? Because life is messy, some
things are hard to change, and there will always be equipment in use that was made before proper grounding practices were in effect.
Unbalanced equipment is another problem: it is everwhere, easily available and inexpensive. All those RCA and
¼" TS connectors found on consumer equipment; effectloops and insert-points on consoles; signal processing boxes;
semi-pro digital and analog tape recorders; computer cards;
mixing consoles; et cetera.
The next several pages give tips on how to successfully
address hooking up unbalanced equipment. Unbalanced
equipment when “blindly” connected with fully balanced
units starts a pattern of hum and undesirable operation,
requiring extra measures to correct the situation.
The Next Best Right Way To Do It
The quickest, quietest and most foolproof method to connect balanced and unbalanced is to transformer isolate all
unbalanced connections. See Figure 2.
Many manufacturers provide several tools for this task,
including Rane. Consult your audio dealer to explore the
options available.
The goal of these adaptors is to allow the use of standard
cables. With these transformer isolation boxes, modification
of cable assemblies is unnecessary. Virtually any two pieces
of audio equipment can be successfully interfaced without
risk of unwanted hum and noise.
Another way to create the necessary isolation is to use a
direct box. Originally named for its use to convert the high
impedance, high level output of an electric guitar to the low
impedance, low level input of a recording console, it allowed
the player to plug “directly” into the console. Now this term
is commonly used to describe any box used to convert unbalanced lines to balanced lines.
The Last Best Right Way To Do It
If transformer isolation is not an option, special cable
assemblies are a last resort. The key here is to prevent the
shield currents from flowing into a unit whose grounding
scheme creates ground loops (hum) in the audio path (i.e.,
most audio equipment).
It is true that connecting both ends of the shield is theoretically the best way to interconnect equipment –though
this assumes the interconnected equipment is internally
grounded properly. Since most equipment is not internally
grounded properly, connecting both ends of the shield is
not often practiced, since doing so usually creates noisy
interconnections.
A common solution to these noisy hum and buzz problems involves disconnecting one end of the shield, even
though one can not buy off-the-shelf cables with the shield
disconnected at one end. The best end to disconnect is the
receiving end. If one end of the shield is disconnected, the
noisy hum current stops flowing and away goes the hum
— but only at low frequencies. A ground-sending-end-only
shield connection minimizes the possibility of high frequency (radio) interference since it prevents the shield from
acting as an antenna to the next input. Many reduce this
potential RF interference by providing an RF path through
UNBALANCED
COMMON (WRONG) PRACTICE
(+)
CASE
RECOMMENDED PRACTICE
2
2
3
(–)
3
1
CHASSIS
GROUND
(+)
CASE
OPTIONAL
(–)
NOT CONNECTED
AT CHASSIS
(PLASTIC JACK)
TRANSFORMER
1/4”
TIP-SLEEVE
1
SIGNAL
GROUND
CHASSIS
GROUND
CHASSIS
GROUND
Figure 1b. Recommmended practice.
BALANCED
CASE LUG MAY
CONNECT TO
CHASSIS
(NOT REQUIRED)
2
3
1
EARTH GROUNDED
METAL ENCLOSURE
CHASSIS IS
GROUNDED TO PIN 1
Figure 2. Transformer Isolation
Interconnection-3
a small capacitor (0.1 or 0.01 microfarad ceramic disc) connected from the lifted end of the shield to the chassis. (This
is referred to as the “hybrid shield termination” where the
sending end is bonded to the chassis and the receiving end is
capacitively coupled. See Neutrik’s EMC-XLR for example.)
The fact that many modern day installers still follow this
one-end-only rule with consistent success indicates this
and other acceptable solutions to RF issues exist, though
the increasing use of digital and wireless technology greatly
increases the possibility of future RF problems.
If you’ve truly isolated your hum problem to a specific
unit, chances are, even though the documentation indicates
proper chassis grounded shields, the suspect unit is not internally grounded properly. Here is where special test cable
assemblies, shown in Figure 3, really come in handy. These
assemblies allow you to connect the shield to chassis ground
at the point of entry, or to pin 1, or to lift one end of the
shield. The task becomes more difficult when the unit you’ve
isolated has multiple inputs and outputs. On a suspect unit
with multiple cables, try various configurations on each connection to find out if special cable assemblies are needed at
more than one point.
See Figure 4 for suggested cable assemblies for your particular interconnection needs. Find the appropriate output
configuration (down the left side) and then match this with
the correct input configuration (across the top of the page.)
Then refer to the following pages for a recommended wiring
diagram.
Ground Lifts
Many units come equipped with ground lift switches. In
only a few cases can it be shown that a ground lift switch
improves ground related noise. (Has a ground lift switch
ever really worked for you?) In reality, the presence of a
ground lift switch greatly reduces a unit’s ability to be
“properly” grounded and therefore immune to ground loop
hums and buzzes. Ground lifts are simply another Band-Aid®
to try in case of grounding problems. It is true that an entire
system of properly grounded equipment, without ground
lift switches, is guaranteed (yes guaranteed) to be hum free.
The problem is most equipment is not (both internally and
externally, AC system wise) grounded properly.
Most units with ground lifts are shipped so the unit is
“grounded” — meaning the chassis is connected to audio
signal ground. (This should be the best and is the “safest”
position for a ground lift switch.) If after hooking up your
system it exhibits excessive hum or buzzing, there is an
incompatibility somewhere in the system’s grounding configuration. In addition to these special cable assemblies that
may help, here are some more things to try:
1. Try combinations of lifting grounds on units supplied
with lift switches (or links). It is wise to do this with the
power off!
2. If you have an entirely balanced system, verify all chassis
are tied to a good earth ground, for safety’s sake and hum
protection. Completely unbalanced systems never earth
ground anything (except cable TV, often a ground loop
source). If you have a mixed balanced and unbalanced
system, do yourself a favor and use isolation transformers or, if you can’t do that, try the special cable assemblies
described here and expect it to take many hours to get
things quiet. May the Force be with you.
3. Balanced units with outboard power supplies (wall warts
or “bumps” in the line cord) do not ground the chassis
through the line cord. Make sure such units are solidly
grounded by tying the chassis to an earth ground using a
star washer for a reliable contact. (Rane always provides
this chassis point as an external screw with a toothed
washer.) Any device with a 3-prong AC plug, such as an
amplifier, may serve as an earth ground point. Rack rails
may or may not serve this purpose depending on screw
locations and paint jobs.
FEMALE
2
C
3
1
RED
BLACK
SHIELD
2-CONDUCTOR SHIELDED CABLE
RED
BLACK
SHIELD
MALE
2
3
1
TEST
WIRE
Figure 3. Test cable
Interconnection-4
GROUND CLIP
Floating, Pseudo, and Quasi-Balancing
During inspection, you may run across a ¼" output called
floating unbalanced, sometimes also called psuedo-balanced
or quasi-balanced. In this configuration, the sleeve of the
output stage is not connected inside the unit and the ring
is connected (usually through a small resistor) to the audio
signal ground. This allows the tip and ring to “appear” as
an equal impedance, not-quite balanced output stage, even
though the output circuitry is unbalanced.
Floating unbalanced often works to drive either a balanced or unbalanced input, depending if a TS or TRS standard cable is plugged into it. When it hums, a special cable
is required. See drawings #11 and #12, and do not make
the cross-coupled modification of tying the ring and sleeve
together.
Winning the Wiring Wars
• Use balanced connections whenever possible, with the
shield bonded to the metal chassis at both ends.
• Transformer isolate all unbalanced connections from balanced connections.
• Use special cable assemblies when unbalanced lines cannot be transformer isolated.
• Any unbalanced cable must be kept under 10 feet
(3 m) in length. Lengths longer than this will amplify all
the nasty side effects of unbalanced circuitry's ground
loops.
Summary
If you are unable to do things correctly (i.e. use fully balanced wiring with shields tied to the chassis at both ends,
or transformer isolate all unbalanced signals from balanced
signals) then there is no guarantee that a hum-free interconnect can be achieved, nor is there a definite scheme that will
assure noise-free operation in all configurations.
References
1. Neil A. Muncy, “Noise Susceptibility in Analog and Digital Signal Processing Systems,” presented at the 97th AES
Convention of Audio Engineering Society in San Francisco, CA, Nov. 1994.
2. Grounding, Shielding, and Interconnections in Analog
& Digital Signal Processing Systems: Understanding the
Basics; Workshops designed and presented by Neil Muncy
and Cal Perkins, at the 97th AES Convention of Audio
Engineering Society in San Francisco, CA, Nov. 1994.
3. The entire June 1995 AES Journal, Vol. 43, No. 6, available
$6 members, $11 nonmembers from the Audio Engineering Society, 60 E. 42nd St., New York, NY, 10165-2520.
4. Phillip Giddings, Audio System Design and Installation
(SAMS, Indiana, 1990).
5. Ralph Morrison, Noise and Other Interfering Signals (Wiley, New York, 1992).
6. Henry W. Ott, Noise Reduction Techniques in Electronic
Systems, 2nd Edition (Wiley, New York, 1988).
7. Cal Perkins, “Measurement Techniques for Debugging
Electronic Systems and Their Instrumentation,” The Proceedings of the 11th International AES Conference: Audio
Test & Measurement, Portland, OR, May 1992, pp. 82-92
(Audio Engineering Society, New York, 1992).
8. Macatee, RaneNote: “Grounding and Shielding Audio
Devices,” Rane Corporation, 1994.
9. Philip Giddings, “Grounding and Shielding for Sound and
Video,” S&VC, Sept. 20th, 1995.
10. AES48-2005: AES standard on interconnections —
Grounding and EMC practices — Shields of connectors
in audio equipment containing active circuitry (Audio
Engineering Society, New York, 2005).
Band-Aid is a registered trademark of Johnson & Johnson
Interconnection-5
To Input
CABLE
CONNECTORS
MALE
BALANCED XLR
FEMALE BALANCED XLR
(NOT A TRANSFORMER,
NOR A CROSS-COUPLED
OUTPUT STAGE)
From Output
FEMALE BALANCED XLR
(EITHER A TRANSFORMER
OR A CROSS-COUPLED
OUTPUT STAGE)
¼” BALANCED TRS
(NOT A TRANSFORMER,
NOR A CROSS-COUPLED
OUTPUT STAGE)
¼” BALANCED TRS
(EITHER A TRANSFORMER
OR A CROSS-COUPLED
OUTPUT STAGE)
¼” FLOATING UNBALANCED
TRS (TIP-RING-SLEEVE)
(SLEEVE IN UNIT = NC)
¼” OR 3.5 mm
UNBALANCED
TS (TIP-SLEEVE)
UNBALANCED RCA
(TIP-SLEEVE)
BALANCED
EUROBLOCK
¼" BALANCED
TRS (TIP-RING-SLEEVE)
¼" OR 3.5mm
UNBALANCED
TS (TIP-SLEEVE)
UNBALANCED RCA
1
2
3
4
1
2
5
6
B
B
BALANCED
EUROBLOCK
+ to +
– to –
SHIELD NC
+ to +
– to –
SHIELD NC
+ to +
– to –
7
8
9
10
7
8
11
12
21
22
11
12
GROUND to GROUND
13
14
15
16
23
17
18
19
20
23
+ to +
– to –
+ to +
– to –
24
+ to +
– to –
A
SHIELD ONLY
TO XLR PIN 1
A
SHIELD ONLY
TO TRS SLEEVE
B
A
A
24
B
A
A
SHIELD ONLY
TO EUROBLOCK
+ to +
– to –
SHIELD NC
+ to +
– to –
GROUND to GROUND
Figure 4. Interconnect chart for locating correct cable assemblies on the following pages.
Note: (A) This configuration uses an “off-the-shelf” cable.
Note: (B) This configuration causes a 6 dB signal loss. Compensate by “turning the system up” 6 dB.
Interconnection-6
2-CONDUCTOR SHIELDED CABLE
2
FEMALE
1=SHIELD
RED
2
2=RED
BLACK
C 3
3=BLACK
SHIELD
1
2-CONDUCTOR SHIELDED CABLE
3
FEMALE
1=SHIELD
RED
2
2=RED
C 3
B 3=NC
SHIELD
1
1-CONDUCTOR SHIELDED CABLE
4
FEMALE
1=SHIELD
RED
2
2=RED
C 3
B 3=NC
SHIELD
1
1-CONDUCTOR SHIELDED CABLE
From Output
5
6
FEMALE
1=SHIELD
RED
2
2-CONDUCTOR SHIELDED CABLE
2=RED
BLACK
C 3
3=BLACK
SHIELD
1
CROSS-COUPLED OUTPUT ONLY: CONNECT PIN 1 TO PIN 3 AT THIS END
AND SET GROUND LIFT SWITCH TO ‘GROUNDED’ (IF PRESENT).
7
RED
BLACK
SHIELD
2-CONDUCTOR SHIELDED CABLE
8
T=RED
R=BLACK
S=SHIELD
RED
BLACK
SHIELD
2-CONDUCTOR SHIELDED CABLE
9B
T=RED
R=NC
S=SHIELD
T=RED
10B R=NC
S=SHIELD
T=RED
R=BLACK
S=SHIELD
RED
1-CONDUCTOR SHIELDED CABLE
SHIELD
RED
SHIELD
RED
BLACK
SHIELD
2
3
1
1=NC
2=RED
3=BLACK
T=RED
R=BLACK
S=NC
RED
T=RED
S=SHIELD
SHIELD
RED
T=RED
S=SHIELD
SHIELD
RED
BLACK
T=RED
S=BLACK
RED
BLACK
RED
BLACK
N/C
T=RED
S=BLACK
MALE
2
3
1
1=NC
2=RED
3=BLACK
RED
BLACK
N/C
T=RED
R=BLACK
S=NC
RED
T=RED
S=BLACK
SHIELD
RED
1-CONDUCTOR SHIELDED CABLE
2-CONDUCTOR SHIELDED CABLE
MALE
RED
BLACK
N/C
FEMALE
1=SHIELD
RED
2
2-CONDUCTOR SHIELDED CABLE
BLACK
2=RED
C 3
SHIELD
3=BLACK
1
CROSS-COUPLED OUTPUT ONLY: CONNECT PIN 1 TO PIN 3 AT THIS END
AND SET GROUND LIFT SWITCH TO ‘GROUNDED’ (IF PRESENT).
T=RED
R=BLACK
S=SHIELD
11
RED
BLACK
N/C
SHIELD
RED
BLACK
To Input
1
FEMALE
1=SHIELD
RED
2
2=RED
BLACK
C 3
3=BLACK
SHIELD
1
T=RED
S=SHIELD
T=RED
S=BLACK
CROSS-COUPLED OUTPUT ONLY: CONNECT RING TO SLEEVE
AT THIS END AND SET GROUND LIFT SWITCH TO ‘GROUNDED’ (IF PRESENT).
12
T=RED
R=BLACK
S=SHIELD
RED
RED
2-CONDUCTOR SHIELDED CABLE
BLACK
BLACK
SHIELD
CROSS-COUPLED OUTPUT ONLY: CONNECT RING TO SLEEVE
AT THIS END AND SET GROUND LIFT SWITCH TO ‘GROUNDED’ (IF PRESENT).
T=RED
S=BLACK
Interconnection-7
14
T=RED
S=BLACK
RED
BLACK
N/C
2-CONDUCTOR SHIELDED CABLE
15A
T=RED
S=SHIELD
16A
T=RED
S=SHIELD
17
From Output
T=RED
S=BLACK
2-CONDUCTOR SHIELDED CABLE
18
T=RED
S=BLACK
T=RED
S=BLACK
19A
T=RED
S=SHIELD
20A
T=RED
S=SHIELD
RED
SHIELD
RED
SHIELD
1-CONDUCTOR SHIELDED CABLE
2-CONDUCTOR SHIELDED CABLE
RED
BLACK
2-CONDUCTOR SHIELDED CABLE
1-CONDUCTOR SHIELDED CABLE
SHIELD
2
3
1
RED
T=RED
S=SHIELD
SHIELD
RED
T=RED
S=SHIELD
SHIELD
RED
BLACK
SHIELD
MALE
2
3
1
T=RED
R=BLACK
A S=SHIELD
RED
BLACK
SHIELD
2-CONDUCTOR SHIELDED CABLE
22A
T=RED
R=BLACK
S=SHIELD
RED
BLACK
SHIELD
2-CONDUCTOR SHIELDED CABLE
RED
T=RED
S=SHIELD
RED
23
(ANY UNBALANCED CONNECTOR)
RED
BLACK
T=RED
S=BLACK
2-CONDUCTOR SHIELDED CABLE
T=RED
S=SHIELD
SHIELD
RED
BLACK
SHIELD
RED
BLACK
SHIELD
1=SHIELD
2=RED
3=BLACK
T=RED
R=BLACK
S=SHIELD
RED
BLACK
SHIELD
1-CONDUCTOR SHIELDED CABLE
SHIELD
1=SHIELD
2=RED
3=BLACK
T=RED
R=BLACK
S=SHIELD
SHIELD
RED
21
MALE
RED
BLACK
SHIELD
1-CONDUCTOR SHIELDED CABLE
RED
BLACK
RED
RED
BLACK
SHIELD
To Input
13
RED
BLACK
N/C
MALE
2
3
1
1=SHIELD
2=RED
3=BLACK
T=RED
R=BLACK
S=SHIELD
(CHECK: NO STANDARD POLARITY ON EUROBLOCKS)
RED
+
BLACK
SHIELD
–
(CHECK: NO STANDARD POLARITY ON EUROBLOCKS)
24
–
+
RED
BLACK
SHIELD
RED (ANY UNBALANCED CONNECTOR)
T=RED
BLACK
S=BLACK
CROSS-COUPLED OUTPUT ONLY: CONNECT BLACK TO SHIELD AT THIS END
AND SET GROUND LIFT SWITCH TO ‘GROUNDED’ (IF PRESENT).
2-CONDUCTOR SHIELDED CABLE
©Rane Corporation 10802 47th Ave. W., Mukilteo WA 98275-5000 USA TEL 425-355-6000 FAX 425-347-7757 WEB rane.com
Interconnection-8
DOC 102907
11/15/2011
C:\CAD Projects\sm26s\SM26S-1.SchDoc
J1
8
5
7
9
4
6
3
2
1
GND
7
9
4
6
3
2
1
GND
D1
D2
D3
D4
D5
D6
R135
30.1k
5
GND
R136
30.1k
2200pF
R138
30.1k
2
3
R50
10.0k
30.1k
R146
GND
30.1k
R137
MIX
R2B
20kB
R16
10.0k
Z4
C84
220pF
GND
R18
R20
3
2
30.1k
R145
MIX
R4B
20kB
10.0k
Z1
C85
2200pF
220pF
GND
R143
30.1k
5
GND
R23
30.1k
2200pF
R22
10.0k
Z5
C86
220pF
GND
R52
10.0k
GND
R154
30.1k
3
2
30.1k
R153
MIX
R24
R7B
20kB
10.0k
Z2
C87
2200pF
220pF
GND
R151
30.1k
5
GND
R152
30.1k
2200pF
R26
10.0k
Z6
C88
220pF
GND
A
B
R49
10.0k
+15
U1A
1
4580
-15
6
5
B
A
GND
R51
10.0k
+15
U15A
1
4580
-15
6
5
B
A
GND
R53
10.0k
+15
U4A
1
4580
-15
6
R67
C9
C12
100kA
6 R1B 4
LEVEL
R80
20.0k
R139
30.1k
2
R142
30.1k
R2A
20kB
30.1k
R141
MIX
51.1
R99
30.1k
R7A
20kB
R157
30.1k
RJ
C
D
C
D9
1SMB15CAT3
CHECKED BY:
SH
J2
MONO
OUT 1
MONO
OUT 2
GND BKT
ST NS TH
GND
J5
GND BKT
ST NS TH
GND
J8
1 of 3
SHEET:
114371
SM26S MONO IN/OUT 1-3
MONO
OUT 3
GND BKT
ST NS TH
GND
10802 47th Avenue West
Mukilteo WA 98275-5098
D10
1SMB15CAT3
D13
1SMB15CAT3
2200pF
R108 Z11
D
D8
1SMB15CAT3
D11
1SMB15CAT3
2200pF
R100 Z7
J3
3pin MALE HDR
GND
R140
30.1k
3
2
1
C11
R158
51.1 Z10
C4
2200pF
820pF
GND
D12
1SMB15CAT3
2200pF
R104 Z9
D
C
51.1 Z8
C2
2200pF
820pF
GND
R150
30.1k
R4A
20kB
30.1k
R149
MIX
R116
100k
51.1
22/16v R115
C1
100k
820pF
51.1
C10 GND R101 GND R102
22/16v
2
GND
R147
30.1k
GND
R148
51.1
R103
J6
3pin MALE HDR
30.1k
22/16v
2
GND
R155
30.1k
51.1
R107
J9
3pin MALE HDR
GND
R156
30.1k
3
2
1
22/16v
51.1 Z12
C6
2200pF
820pF
GND
DRAWN BY:
RI TO SMT CONVERSION
WAS 110401
ACTION:
GND
R120
100k
51.1
22/16v R119
C5
100k
820pF
51.1
C16 GND R109 GND R110
C17
MIX
R118
100k
51.1
22/16v R117
C3
100k
820pF
51.1
C13 GND R105 GND R106
C14
1
2
3
R82
4580
-15
+15
U5A
1
33pF
C40
20.0k
R84
4580
-15
+15
U3A
1
33pF
C38
20.0k
-15
4580
+15
U2A
1
C36
2
GND
3
2
GND
3
2
GND
3
33pF
R79
C35
U2B
4580
20.0k
R83
20.0k
R81
20.0k
33pF
7
100kA
1 R1A 3
CW
6
5
R68
40.2kGND
100kA
6 R3B 4
LEVEL
C37
33pF
U3B
4580
LEVEL
C39
33pF
U5B
4580
7
100kA
1 R6A 3
CW
6
5
7
100kA
1 R3A 3
CW
6
5
100kA
6 R6B 4
R70
40.2kGND
GND
40.2k 22/16v
U1B
7
4580
R69
C15
GND
R72
40.2kGND
GND
40.2k 22/16v
U15B
7
4580
R71
7
40.2k 22/16v
U4B
CW
J4
8
5
J7
8
5
7
9
4
6
3
2
1
R54
10.0k
4580
CW
CW
3
3
MONO
IN 1
MONO
IN 2
MONO
IN 3
GND
10.0k
C89
220pF
GND
Z3
2200pF
GND
5
GND
Main
3
1
1
1
8
4
8
4
8
4
5
2
5
CW
CW
CW
2
5
2
8
4
8
4
8
4
6
4
6
4
6
4
1SMB15CAT3
x2
1SMB15CAT3
x2
1SMB15CAT3
x2
1/4 SWITCHING
1/4 SWITCHING
1/4 SWITCHING
11/15/2011
C:\CAD Projects\sm26s\SM26S-2.SchDoc
J10
8
5
J13
8
5
J16
8
5
7
9
4
6
3
2
1
GND
7
9
4
6
3
2
1
GND
7
9
4
6
3
2
1
D14
D15
D16
D17
D18
D19
R159
30.1k
5
GND
R160
30.1k
2200pF
R162
30.1k
2
3
R56
10.0k
30.1k
R170
GND
30.1k
R161
MIX
R9B
20kB
R34
10.0k
Z16
C90
220pF
GND
R36
R38
30.1k
R178
GND
R58
10.0k
3
2
30.1k
R169
MIX
R11B
20kB
10.0k
Z13
C91
2200pF
220pF
GND
R167
30.1k
5
GND
R168
30.1k
2200pF
R40
10.0k
Z17
C92
220pF
GND
R42
3
2
30.1k
R177
MIX
R13B
20kB
10.0k
Z14
C93
2200pF
220pF
GND
R175
30.1k
5
GND
R176
30.1k
2200pF
R44
10.0k
Z18
C94
220pF
GND
R60
10.0k
A
B
R55
4580
10.0k
+15
U16A
1
-15
6
5
B
A
GND
R57
10.0k
+15
U8A
1
4580
-15
6
5
B
A
GND
R59
10.0k
+15
U17A
1
4580
-15
6
R73
C18
C21
100kA
6 R8B 4
LEVEL
R86
R163
30.1k
2
R166
30.1k
R165
MIX
30.1k
R9A
20kB
R121
100k
51.1
R111
51.1
C74
820pF
C
D
D
D21
1SMB15CAT3
D24
1SMB15CAT3
2200pF
R189 Z21
C
51.1 Z22
C77 2200pF
820pF
GND
R182
RJ
CHECKED BY:
SH
J19
MONO
OUT 4
MONO
OUT 5
GND BKT
ST NS TH
GND
J14
GND BKT
ST NS TH
GND
J17
2 of 3
SHEET:
114371
SM26S MONO IN/OUT 4-6
MONO
OUT 6
GND BKT
ST NS TH
GND
10802 47th Avenue West
Mukilteo WA 98275-5098
D22
1SMB15CAT3
D30
1SMB15CAT3
2200pF
R193 Z23
D
D20
1SMB15CAT3
D23
1SMB15CAT3
2200pF
R112 Z19
J12
3pin MALE HDR
GND
R164
30.1k
3
20.0k
2
1
C20
22/16v
51.1
R188
C
51.1 Z20
C75 2200pF
820pF
GND
R174
30.1k
R11A
20kB
30.1k
R173
MIX
51.1
R122
100k
C19 GND R113 GND R114
22/16v
GND
R171
2
GND
R172
30.1k
30.1k
22/16v
2
GND
R179
30.1k
30.1k
R181
MIX
51.1
R192
J18
3pin MALE HDR
GND
R180
30.1k
3
2
1
22/16v
51.1 Z24
C79 2200pF
820pF
GND
DRAWN BY:
RI TO SMT CONVERSION
WAS 110401
ACTION:
GND
R126
100k
51.1
22/16v R125
C78
100k
820pF
51.1
C25 GND R194 GND R195
C26
30.1k
R13A
20kB
R124
100k
51.1
22/16v R123
C76
100k
820pF
51.1
C22 GND R190 GND R191
C23
1
2
3
R88
C44
33pF
+15
U7A
1
4580
-15
R90
C46
20.0k
33pF
+15
U10A
1
4580
-15
J15
3pin MALE HDR
20.0k
-15
4580
+15
U6A
1
C42
2
GND
3
2
GND
3
2
GND
3
33pF
R85
C41
U6B
4580
20.0k
R89
20.0k
R87
20.0k
33pF
7
100kA
1 R8A 3
CW
6
5
R74
40.2kGND
100kA
6 R10B 4
LEVEL
C43
33pF
U7B
4580
LEVEL
4580
U10B
7
33pF
C45
100kA
1 R12A 3
CW
6
5
7
100kA
1 R10A 3
CW
6
5
100kA
6 R12B 4
R76
40.2kGND
GND
40.2k 22/16v
U16B
7
4580
R75
C24
GND
40.2k 22/16v
U8B
7
4580
R77
R78
40.2kGND
GND
40.2k 22/16v
U17B
7
4580
CW
CW
3
CW
MONO
IN 4
MONO
IN 5
MONO
IN 6
GND
10.0k
C95
220pF
GND
Z15
2200pF
GND
5
GND
Main
3
1
1
3
8
4
8
4
8
4
1
5
2
5
CW
CW
CW
2
5
2
8
4
8
4
8
4
6
4
6
4
6
4
1SMB15CAT3
x2
1SMB15CAT3
x2
1SMB15CAT3
x2
1/4 SWITCHING
1/4 SWITCHING
1/4 SWITCHING
LEFT
EXPAND
OUT
RIGHT
EXPAND
OUT
J20A
GND
R5
10.0k
C7
220pF
GND GND
R17
2200pF
Z25
D31
D32
R19
10.0k
Z26
C8
2200pF
220pF
GND
2200pF
Z27
D34
D35
3
2
6
5
C100
22pF
R62
10.0k
U9B
7
MASTER
INPUT
LEVEL
-15
C105
22pF
3
+
+
GND
2
R14A
10kA
5
R14B
10kA
GND
R92
20.0k
C27
22/16v
2
3
C101
22pF
R91
20.0k
R65
10.0k
GND
C104
R93
22pF
R94
FB
7
5
6
+15
7
1
U11A
4580
-15
130
+
130
R236
C202
470/25v
C185
0.1
R238
1.24k
C203
470/25v
+
MURS160
D29
MURS160
D28
4580
U11B
20.0k
6
5
R66
10.0k
T2
6
10
8
9
20.0k
C28
GND
22/16v
2
4
5
GND
D25
P6SMB160AT
D27
D26
MURS160
R234
1
7
600uH
C190
C
COMP
0.001 X1Y1
8 R235
LED
E
GND
NC
U36
4148
1
36.5
C189
47/50v
C193
6.8/400v
D33
DF06M
1
GND
MASTER
INPUT
LEVEL
10.0k
+15U9A
4580
1
22pF
R64
C103
C102
22pF
4580
R61
10.0k
GND
2
3
2
R63
10.0k
GND
10.0k
C96
220pF
GND
GND
R21
T1
10.0k
C97
220pF
GND
Z28
2200pF
1
20mH
C200
0.001 X1Y2
3
4
C192
1/50v
8
4
ST SW TH
J20B
GND
ST SW TH
J21A
GND
ST SW TH
J21B
GND
ST SW TH
C195
0.0022 X1Y2
C197
4
0.33 X2
C199
0.001 X1Y2
S
DRAIN
VIPER50
U38
Vdd
OSC
+
2
3
4
NC
R258
10.0k
L5
A
B
10uH
L6
10uH
R259
51.1k
+
H1
+
C182
150/25v
H3
TP1
H4
TP2
C183 GND
150/25v
H2
R128
100k
C
R127
100k
D
+15
-15
PWR
H8
R27
10.0k
D7
YEL
H7
R183
10.0k
H5
GND
6
5
C32
22/16v
R95
C63
0.1
C69
0.1
C64
0.1
C70
0.1
C65
0.1
20.0k
R97
20.0k
GND
SH
6
33pF
U14B
7
+15
U14A
1
4580
-15
R31
1.00k
R98
20.0k
C50
7
-15
4580
+15
U13A
1
33pF
U13B
R32
4580
1.00k
+15
C66
0.1
6
5
GND
3
2
2
3
GND4580
5
R96
C29
20.0k
C48
GND
5
R15B
10kA
C62
0.1
C68
0.1
CHECKED BY:
C30
R200
R201
51.1
R130 51.1
100k
C82
820pF
GND
R131 51.1
100k
R202
R197
51.1
C83
820pF
GND
R203
GND
22/16v
C31
R196
GND
22/16v
C33
51.1
R133 51.1
100k
C80
820pF
GND
D36
2200pF
Z33
1SMB15CAT3
J22A
LEFT MIX
OUTPUT
ST SW TH
D37
GND
1SMB15CAT3
Z34
2200pF
2200pF
Z35
D38
J22B
1SMB15CAT3
RIGHT MIX
OUTPUT
R2C
100kA
R1C
R8C
20kB
R7C
100kA
R6C
R13C
100kA
R12C
20kB
R11C
100kA
R10C
10kA
R15C
10kA
R14C
ST SW TH
D39
GND
1SMB15CAT3
Z36
2200pF
20kB
100kA
R199
R3C
R9C
R198
GND
22/16v
C34
22/16v
100kA
51.1
C81
820pF
GND
R4C
GND
20kB
GND
20kB
GND
20kB
R134 51.1
100k
GND
3 of 3
SHEET:
114371
SM26S EXPAND/MIX/PWR SUPPLY
GND
10802 47th Avenue West
Mukilteo WA 98275-5098
GND
-15
C71
0.1
C67
0.1
DECOUPLING CAPS
GND
22/16v
R132
C53
0.1
2
R15A
10kA
100k
C49
33pF
U12B
7
4580
33pF
+15
U12A
1
100k
C47
R129
MASTER
OUTPUT
LEVEL
GND4580
2
3
-15
C52
0.1
C56
0.1
GND
C51
0.1
C55
0.1
MASTER
OUTPUT
LEVEL
C54
0.1
ACTION:
RJ
RI TO SMT CONVERSION
WAS 110401
DRAWN BY:
8
CW
CW
FOD2741
GND
Main
CW
CW
4
8
4
3
1
6
4
8
4
8
4
1
6
4
MASTER
INPUT
LEFT
F3
T 1A 250V
C196
0.0022 X1Y2
C201
2
1
C187
0.068
R260
1.00k
3
4
MASTER
INPUT
RIGHT
J11
3
H
2
G
1
N
IEC PWR
H6
0.0022 X1Y2
R144
10.0k
C188
0.0022
COMP
5
1SMB15CAT3
x2
11/15/2011
C:\CAD Projects\sm26s\SM26S-3.SchDoc
GNDP
1SMB15CAT3
x2
WARRANTY
FACTORY AUTHORIZED SERVICE
Your unit may be serviced by the Rane Factory or any Authorized Rane Service Center. To find a Service Center near you, please call
the Rane factory, or check the Rane website. Please do not return your unit to Rane without prior authorization.
Rane Corporation
To obtain service or a Return Authorization, please phone 425-355-6000
or Fax 425-347-7757
The current list of U.S. Rane Authorized Service Centers is found on our website: www.rane.com/service.html
LIMITED DOMESTIC WARRANTY
RANE CORPORATION WARRANTS ALL RANE PRODUCTS (EXCEPT THOSE ITEMS CLASSIFIED AS WEAR PARTS, AND LISTED ON THE
MANUAL-1 PAGE OF EACH OPERATORS MANUAL) PURCHASED IN THE USA AGAINST DEFECTS IN MATERIAL OR WORKMANSHIP
FOR A PERIOD OF TWO (2) YEARS. WEAR PARTS ARE LIMITED TO A PERIOD OF NINETY (90) DAYS FROM THE INITIAL DATE OF
RETAIL PURCHASE FROM AN AUTHORIZED RANE DEALER—WEAR PARTS REQUIRE PROOF OF PURCHASE DATE. This limited
warranty extends to all purchasers or owners of the product during the warranty period beginning with the original retail purchase. Rane Corporation
does not, however, warrant its products against any and all defects: 1) arising out of material or workmanship not provided or furnished by Rane, or
2) resulting from abnormal use of the product or use in violation of instructions, or 3) in products repaired or serviced by other than authorized Rane
repair facilities, or 4) in products with removed or defaced serial numbers, or 5) in components or parts or products expressly warranted by another
manufacturer. Rane agrees to supply all parts and labor to repair or replace defects covered by this limited warranty with parts or products of original
or improved design, at its option in each respect, if the defective product is shipped prior to the end of the warranty period to any Rane authorized
warranty repair facility in the U.S. or to the Rane factory in the original packaging or a replacement supplied by Rane, with all transportation costs and
full insurance paid each way by the purchaser or owner.
LIMITED WARRANTY OUTSIDE THE U.S.A.
RANE PRODUCTS ARE WARRANTED ONLY IN THE COUNTRY WHERE PURCHASED, THROUGH THE AUTHORIZED RANE
DISTRIBUTOR IN THAT COUNTRY, AGAINST DEFECTS IN MATERIAL OR WORKMANSHIP, THE SPECIFIC PERIOD OF THIS
LIMITED WARRANTY SHALL BE THAT WHICH IS DESCRIBED TO THE ORIGINAL RETAIL PURCHASER BY THE AUTHORIZED
RANE DEALER OR DISTRIBUTOR AT THE TIME OF PURCHASE. Rane Corporation does not, however, warrant its products against any and
all defects: 1) arising out of materials or workmanship not provided or furnished by Rane, or 2) resulting from abnormal use of the product or use in
violation of instructions, or 3) in products repaired or serviced by other than authorized Rane repair facilities, or 4) in products with removed or defaced
serial numbers, or 5) in components or parts or products expressly warranted by another manufacturer. Rane agrees, through the applicable authorized
distributor, to repair or replace defects covered by this limited warranty with parts or products of original or improved design, at its option in each respect,
if the defective product is shipped prior to the end of the warranty period to the designated authorized Rane warranty repair facility in the country
where purchased, or to the Rane factory in the U.S., in the original packaging or a replacement supplied by Rane, with all transportation costs and full
insurance paid each way by the purchaser or owner.
ALL REMEDIES AND THE MEASURE OF DAMAGES ARE LIMITED TO THE ABOVE SERVICES, IT IS POSSIBLE THAT ECONOMIC
LOSS OR INJURY TO PERSON OR PROPERTY MAY RESULT FROM THE FAILURE OF THE PRODUCT; HOWEVER, EVEN IF RANE
HAS BEEN ADVISED OF THIS POSSIBILITY, THIS LIMITED WARRANTY DOES NOT COVER ANY SUCH CONSEQUENTIAL OR
INCIDENTAL DAMAGES. SOME STATES OR COUNTRIES DO NOT ALLOW THE LIMITATIONS OR EXCLUSION OF INCIDENTAL
OR CONSEQUENTIAL DAMAGES, SO THE ABOVE LIMITATION MAY NOT APPLY TO YOU.
ANY AND ALL WARRANTIES, EXPRESS OR IMPLIED, ARISING BY LAW, COURSE OF DEALING, COURSE OF PERFORMANCE, USAGE
OF TRADE, OR OTHERWISE, INCLUDING BUT NOT LIMITED TO IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
FOR A PARTICULAR PURPOSE, ARE LIMITED TO A PERIOD OF TWO (2) YEARS FROM EITHER THE DATE OF ORIGINAL RETAIL
PURCHASE OR, IN THE EVENT NO PROOF OF PURCHASE DATE IS AVAILABLE, THE DATE OF MANUFACTURE, SOME STATES
OR COUNTRIES DO NOT ALLOW LIMITATIONS ON HOW LONG AN IMPLIED WARRANTY LASTS, SO THE ABOVE LIMITATIONS
MAY NOT APPLY TO YOU. THIS LIMITED WARRANTY GIVES YOU SPECIFIC LEGAL RIGHTS, AND YOU MAY ALSO HAVE OTHER
RIGHTS WHICH VARY FROM STATE TO STATE, COUNTRY TO COUNTRY.
Warranty-1
WARRANTY PROCEDURE - Only Valid in the USA
NOTICE! You must complete and return the warranty card or register your
product online to extend the Warranty from 2 years to 3 years!
TO VALIDATE YOUR EXTENDED WARRANTY: Use the postcard that came in the box with your unit, or go to www.rane.com and
click on New Product Registration. Fill out the warranty completely, being sure to include the model and serial number of the unit
since this is how warranties are tracked. If your Rane product was purchased in the USA, mail the completed card or register online with
to Rane Corporation within 10 days from the date of purchase. If you purchased the product outside the USA you must file your
warranty registration with the Rane Distributor in that country. It is advised that you keep your bill of sale as proof of purchase,
should any difficulties arise concerning the registration of the warranty card. NOTICE: IT IS NOT NECESSARY TO REGISTER IN
ORDER TO RECEIVE RANE CORPORATION’S STANDARD TWO YEAR LIMITED WARRANTY.
WARRANTY REGISTRATION is made and tracked by model and serial numbers only, not by the purchaser’s or owner’s name.
Therefore any warranty correspondence or inquires must include the model and serial number of the product in question. Be sure to fill
in the model and serial number in the space provided below and keep this in a safe place for future reference.
WARRANTY SERVICE MUST BE PERFORMED ONLY BY AN AUTHORIZED RANE SERVICE FACILITY LOCATED IN
THE COUNTRY WHERE THE UNIT WAS PURCHASED, OR (if product was purchased in the USA) AT THE RANE FACTORY
IN THE USA. If the product is being sent to Rane for repair, please call the factory for a Return Authorization number. We recommend
advance notice be given to the repair facility to avoid possible needless shipment in case the problem can be solved over the phone.
UNAUTHORIZED SERVICE PERFORMED ON ANY RANE PRODUCT WILL VOID ITS EXISTING FACTORY WARRANTY.
FACTORY SERVICE
If you wish your Rane product to be serviced at the factory, it must be shipped fully insured, in the original packing box or equivalent.
This warranty will not cover repairs on products damaged through improper packaging. If possible, avoid sending products through the
mail. Be sure to include in the package:
1. Complete return street shipping address (P.O. Box numbers are not acceptable).
2. A detailed description of any problems experienced, including the make and model numbers of any other system equipment.
3. Remote power supply, if applicable.
Repaired products purchased in the U.S. will be returned prepaid freight via the same method they were sent to Rane. Products purchased
in the USA, but sent to the factory from outside the USA must include return freight funds, and the sender is fully responsible for all
customs procedures, duties, tariffs and deposits.
In order to qualify for Rane’s one year extended warranty (for a total of 3
years parts and labor), the warranty must be completely filled out and sent to
us immediately. Valid in USA only.
We recommend you write your serial number here in your owners
manual and on your sales receipt for your records.
SERIAL NUMBER:______________________________________PURCHASE DATE:__________________________________
©Rane Corporation 10802 47th Ave. W., Mukilteo WA 98275-5000 TEL 425-355-6000 FAX 425-347-7757 WEB www.rane.com
Warranty-2
108360
EU Declaration of Conformity
Product Model: SM26S
Serial Numbers: 900000 – 999999
Product Type: Professional Audio Signal Processing
Manufacturer: Rane Corporation
Address: 10802 47th Avenue West, Mukilteo WA 98275-5000 USA
This declaration is issued under the sole responsibility of Rane Corporation.
The object of the declaration described above is in conformity with the relevant Union harmonisation legislation:
2014/35/EUThe Low Voltage Directive
2014/30/EUThe Electromagnetic Compatibility Directive
2012/19/EU
The Waste Electrical and Electronic Equipment Directive
2011/65/EU
The Restriction of Hazardous Substances Directive
2001/95/ECThe General Product Safety Directive
References to the relevant harmonised standards used in relation to which conformity is declared:
EN60065:2002/A1:2006/A11:2008/A2:2010/A12:2011
Safety for audio, video and similar electronic apparatus.
EN55103-1:2009/AM1:2012
Compatibility of professional electronic A/V apparatus emissions.
EN55103-2:2009
Compatibility of professional electronic A/V apparatus immunity.
EN50581:2012
Technical documentation for RoHS assessment of electronic products.
Additional Information:
Environment E2
CE mark first affixed in 2007
In order for the customer to maintain compliance with these regulations, high quality shielded cable must be used for
interconnection to other equipment. No changes or modification of the equipment, other than that expressly outlined by the
manufacturer, are allowed. The user of this equipment shall accept full responsibility for compliance with Union harmonisation
legislation in the event that the equipment is modified without written consent of the manufacturer.
EN55103-2 Immunity Results: Test Description
RF Electromagnetic Fields Immunity
80 MHz - 1000 MHz, 1 kHz AM, 80% depth, 3V/m
Conducted RF Disturbances Immunity
150 kHz - 80 MHz, 1 kHz AM, 80% depth, 3V rms
Magnetic Fields Immunity
50 Hz - 10 kHz, 4.0 - 0.4 A/m
THD+N: 4 dBu, 400 Hz, BW 20 Hz - 20 kHz
Measurement
Conditions
<-66 dB
<-31 dB
80 MHz - 200 MHz
200 MHz - 1000 MHz
<-82 dB
<-82 dB
Power Lines
Signal Lines
<-70 dB
Signed for and on behalf of: Rane Corporation
Place of issue: Mukilteo WA USA Date of issue: May 31, 2007
Name: Michaël Rollins
Function: Compliance Engineer
Signature:
SM26S
RANE CORPORATION
100-240 V
50/60 Hz 7 WATTS
R
COMMERCIAL AUDIO
EQUIPMENT 24TJ
MIX OUTPUT
RIGHT
LEFT
6
5
3
MONO OUTPUTS
4
2
1
This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions:
(1) this device may not cause harmful interference, and (2) this device must accept any interference
received, including interference that may cause undesired operation. CAN ICES-3 (B)/NMB-3(B)
EXPAND OUT
MASTER IN
RIGHT
LEFT
6
5
3
MONO INPUTS
4
2
1
All Inputs and Outputs are Balanced: Tip = positive (+), Ring = Negative (–), Sleeve = Chassis Ground.
All audio jacks are Class 2 wiring.
SPLITTER / MIXER
SM26S