Tone Frenzy

Building the “Tone Frenzy” Amp
A Torres Engineering amp design kit
Our good friend Jeff D. is a regular at Torres
Engineering and has the great “Tone Frenzy” web
page (http://www.tonefrenzy.com) dedicated to
getting “the tone.”
We are always looking at and testing real
interesting/unusual guitars and effects Jeff brings
in to the shop.
Jeff also has a couple of Torres Engineering
Prototype amps including the world famous
“mini-Dual Marshall” and the “Tone Frenzy
Champ Amp” described here.
The latest project was a relatively ill Fender
Champ amp. Since it was in rough condition we
decided to get some good stuff going in it and
Jeff wanted to develop the ultimate single ended
rock amp at a non-bankruptcy price.
First we added a real tube reverb circuit,
complete with extra tubes, transformer and 3
spring reverb tank.
Next it was an extra gain stage for some full-on
overdrive and sustain.
After all that sounded perfect, Jeff wanted to step
the power up from the single ended 6V6 to a 6L6
- cool!
One of these mods can be done to the amp fairly
easily, but when you get to adding multiple tubes
for a reverb, increasing the filament string current
requirements, needing more power trans current,
and then mis-matching the output transformer,
the project gets more complex.
To make it a dependable amp, and get the last
ounce of performance from the amp, all the
design factors have to be accounted for.
transformer to take the load off of the original
champ power transformer filament winding.
The complete amp project uses a power
transformer with enough current capacity for
all the tubes, filaments and rectifier tube.
Also hefty 1 x 6L6 output transformers of the
correct primary impedance, and capable of
driving an 8 ohm 10" speaker in stead of the
now-overpowered 8" champ speaker.
Of course all this doesn’t fit!! Adding two
12AX7 tubes to the chassis and such, plus
transformers (filament, reverb, and new output
about 3 times as large), and fitting it all back
into the champ cabinet is a real 3 dimensional
design project, we won’t go into all that, but will
build a new amp from scratch taking all design
considerations into mind, and making still more
improvements.
Check out the block diagram. I’ll go through
each of the stages in the process of building a
complete single ended 8 to 10 watt amp with
reverb and killer “Tone Frenzy tone.”
Input of the amp is to the extra gain stage. It has
its own volume, and outputs to a switch jack
that allows you to bypass it and plug into the
“normal” fender style preamp.
The preamp is modified a bit to get a fuller,
warmer tone, and better frequency response
when used with a better power supply and high
quality (higher than the original Fender) output
transformer.
A complete reverb circuit is next - reverb circuit
are actually in parallel with the main amp circuit,
and are actually a little amplifier driving the
reverb springs.
The Champs ended up with an auxiliary filament
This is a free project. There is no tech help available unless the kit has been purchased from Torres Engineering
Page 1
A new driver circuit using both sides of a tube in
parallel is used to get more current drive to the
power tube.
A single stage of a 12AX7 as found in the champ
is somewhat underpowered and incapable of
really driving a 6L6 with enough “voltage swing”
to make the tube come to life.
The 6L6 is wired in pentode for the most output
power. It would also be possible to use a high
end audiophile ultra-linear single ended air gap
transformer for lots and lots of clean power from
the amp. I certainly will try that on the completed
model.
A whole new power supply is designed for this
amp. Single ended amps do not have the benefit
of hum cancelling that push-pull amps have.
Some degree of hum exists in the very simple
champ power supply circuit. This is completely
eliminated for a professional quality low noise
amp.
One of the difficulties with single-ended amps,
those using only one power tube, is the loss of the
"humbucking effect" from two power tubes in
push pull. This push-pull humbucking effect
reduces the hum in the amp (called "ripple")
quite a bit, making it easier to design the DC
power supply for the amplifier.
Without the noise reduction of push-pull, many
(almost all) vintage single ended amps have
noticeable residual hum in their power supplies
and in the audio signal.
After all, these were designed as cheap amps.
Low cost for practice or beginners, not at all for
the uses we put them to today - recording, high
gain, higher expectations in performance etc.
It is fairly easy to reduce the ripple of the power
supply, but it was not considered in the design of
the vintage amps.
The Tone Frenzy amp is designed to be a
professional level amp with very low noise and
no apparent ripple sneaking into the audio signal
from the power supply.
Adding an extra stage of filter capacitance,
separated from the rectifier by a low value
resistor reduces the power supply ripple by a
factor of over 100 -(see "Inside Tube Amps" by
Dan Torres for full details on the math and
ripple reduction).
So take a look at the drawing for the added filter
cap and resistor.
This power supply also feature a "turn on" cap at
the output of the rectifier tube. A .1 mfd 600V
metal film cap (we have them custom made just
for this purpose.) This cap keeps the rectifier
tube from seeing an open circuit when turned on
with the standby switch open.
Since voltages are fairly low for a single ended
amplifier, filter caps in series, as found on other
higher voltage push pull amps, are not
necessary.
The first 47 mfd filter cap (rated for 450 volts)
has a 100k resistor in parallel with it. This
resistor is a "capacitor bleed" resistor. It will
bleed off the stored cap voltages when the amp
is turned off.
At 100k it adds a bit of regulation to the power
supply - helps it remain more stable. 50k would
add more regulation but would have to be a 5 or
10 watt resistor and would also bleed off some
of the B+ voltage.
The second 47 mfd cap (450V) is the first node
of the power supply - called B+1. From there
the power supply is pretty standard single ended
vintage amp.
The second resistor, a 1k 1 watt could be
replaced by a choke for a smoother sounding
This is a free project. There is no tech help available unless the kit has been purchased from Torres Engineering
Page 2
amp with higher voltages appearing down the
power supply. The final version of the amp will,
most likely, include a choke.
the gain to provide more of a “tube screamer”
subtle “push” effect with lots of compression,
low noise and clarity. (Feedback reduces noise.)
When building the amp new, the old fashioned
Fender one piece "can caps" won't be used - a
separate power supply board is used to
accommodate the individual capacitors.
The 500k pot at the output of the first stage
controls the amount of added gain from the
extra circuit.
This amp has a modern preamp with a full tone
circuit, single ended 6L6 tube instead of a 6V6
for more power, plus an extra overdrive stage,
and a full tube/transformer driven reverb - a very
cool and versatile amp.
Pint to point eyelet circuit boards are available
Torres Engineering, as well as a kit for the entire
“Tone Frenzy Amp.”
Ok, take a look at the preamp circuit.
This isn’t a super complex circuit, but it has a
few “twists” of interest, and the high gain and
high performance will require top quality
assembly and materials.
Take a look at the schematic for the details of the
preamp circuit.
Input is pretty normal with a grid load resistor
and into the first stage - half of a 12AX7 tube.
This is the overdrive stage. Plugging into its jack
provides an extra stage of gain to “push” the rest
of the preamp into pleasing tube distortion with
lots of sustain.
This feeds into another input jack (#2) with a
switch. The switch disconnects the overdrive
stage when you plug into jack #2 for a clean
tone - easy, not a new idea. This type of circuit
is found on many amps back to the 1970's,
boogie, Marshall etc.
Following Jack #2 is a fairly standard Fender
amp tone circuit comprising two more stages of
a 12AX7 tube. There are changes in the tone
control circuit (called the “tone stack” by some)
and in the tube gain stages to adapt the
frequency response for the single ended 6L6
tube and to modify the overall tone so the “Tone
Frenzy amp” sounds like it is a 30 year old
classic Fender.
A modified reverb circuit is inserted right after
the tone control recover stage. This reverb
circuit is modified to have the reverb effect
cover a wider frequency range and the input
dwell to the reverb driver tube (specified as a
12AT7) is slightly reduced for better application
in a high gain amplifier.
Reverb return comes back to the circuit using
the Reverb pot as the following stage’s grid load
resistor.
The “trick” here is the local feedback1 shown as a
.1 mfd. capacitor and 10 meg resistor going from
the input of the tube stage to the output. Instead
of blasting hard-to-control overdrive typical of
1970's designs, this local feedback circuit lowers
Overall, a circuit that will work beautifully if
attention to detail and layout are done correctly.
1
This is a fairly easy part of the project, the final
schematic is included with all the power supply
connections and entire amp shown.
Not to be confused with the squeal feedback of a
microphone. This is signal feedback designed to lower the
gain of the input by sending some of the output back to the
input out of phase to reduce gain
This is the final section of the amp, the driver
and power tube.
This is a free project. There is no tech help available unless the kit has been purchased from Torres Engineering
Page 3
The “driver” is a 12AT7 tube, wired with both
stages in parallel for more current capacity and a
stronger drive to the 6L6 power tube.
(Class A tubes require considerably more drive
than the standard Class AB amps. A 6L6 in class
A requires much more drive than a 6V6 to really
get the tube working right.)
The cathode bias resistor for the 12AT7 may
need to be adjusted a bit to get 2.5 ma current
draw for the tube. A one ohm (1 ohm) resistor is
installed in the cathode circuit of the 12AT7. The
current converted to milliVOLTS can be read
across this resistor with your VOM meter. If the
current draw is too high, use a larger resistor (1k
for example.) If the current draw is too low, use a
lower value resistor (680 ohm for example.)
12AT7 tubes vary considerably in response so
this adjustment may be necessary.
The 8 pin 6L6 tube is next, with drive at the
control grid from the 12AT7 plate to a 250k
master volume which acts as the plate load
resistor for the 6V6 (can not be left out. If you do
not wish to have a master volume. Replace the
pot with a 220K 1W resistor.
This is a cathode biased output. Contrary to
popular (internet) knowledge, cathode bias amps
can and do need to have the bias adjusted.
The process is fairly simple. Again, a one ohm
resistor in installed in the cathode circuit.
The current draw of the tube (milliamperes - ma)
can be read at this resistor. The resistor
automatically converts the current into a voltage
figure.
The plate voltage using the specified transformer,
is about 330 volts with the 5V4 rectifier tube
specified.
Place your VOM meter red lead at the tube side
of the 1 ohm resistor, and the black lead at the
cathode resistor side of the same 1 ohm resistor.
You must have clips on the meter leads to be
sure you don’t get a shock.
Notice: this kind of work requires the amp to
be on. You must be experienced and trained
in working with high voltages and current,
and knowledgeable of the dangers and
concerns in doing this kind of work. If you do
not have the correct experience and verified
training, do not work on any kind of
electronic device when it is turned on.
The current draw of the tube can be read on
your VOM meter in millivolts. The single ended
Class A 6L6 should draw between 40 and 53 ma
(mv) adjust the cathode bias resistor (5 watt
minimum, 10 watt suggested) to get as close as
possible to this current reading.
You can adjust the required current if you have
slightly higher or lower plate voltages by
consulting the bias charts found in “Inside Tube
Amps” by Dan Torres
The new 6L6 sounds very, very good at 50 ma
in this amp design.
The output transformer is rated for about 15
watts to be sure it has sufficient headroom.
Primary impedance is best at 4.1k to 4.2k for a 4
or 8 ohm load. The transformer specified on the
schematic has both output impedances available.
Copyright ©® Dan Torres 2004
all rights reserved.
May not be reproduced in any media existing
now or to exist in the future.
For one time personal use only.
Revised Wednesday, September 15, 2004
This is a free project. There is no tech help available unless the kit has been purchased from Torres Engineering
Page 4
The Tone Frenzy Amp Block Diagram
2
1
extra gain
stage
switch
volume
switch
1
Input preamp
tone circuit
preamp volume
single ended
power tube
single ended
driver circuit
output transformer
speaker
volume
reverb circuit
amp circuit only (power supply not included)
DANGER
Drawing By Dan Torres
DANGER
C
HIGH
VOLTAGE
CAUT ION
300 - 400
VOLTS
Copyright
Dan Torres 2000
This circuit is copyrighten. not for commercial use of
any kind. May not be reproduced in any media existing now or to
exist in the future. For one-time only personal use only.
Protected by International Copyright laws.
Filament Wiring
green (usually) from power; transformer
the pilot light and hum balance can be connected
anywhere along the filament string (to any tube)
they do not have to be at the ends as shown here.
filament wires have to connect all the tubes
The filament wiring is Parallel - all connections are
identical
9
5
6
7
4
8
3
pilot light
2
1
12AX7
12AT7
12AU7
5751
12AY7 etc.
7
FIL
8
6
1
7
2
6
8
FIL
1
2
3
4 &5
green (usually) from power; transformer
9
FIL
3
FIL
4 &5
actually the wires should be twisted around each other
twist as tight as possible
route filament wires away from any other signal wires in the amp
Power tube connections (6L6, 6V6, EL34, 6CA7, 6550, KT66, KT88)
are pins 2 and 7
Preamp tube filaments are pin 9 and pins 4 and 5 - pins 4 & 5 are connected together
200 ohm
yellow
DANGER
VOLTS
white
rectifier tube
5 Volt
recitfier tube
filament
primary
high volt B+
center
tap
red
C
DANGER
HIGH
VO LTAG E
Dan Torres
8
6
red/yellow
secondary
red
4
2
5V4
rectifier tube
6.3 V olt
green
Copyright
yellow
power transformer
fuse
black
power
switch
Drawing By Dan Torres
CAUTION
300 - 400
This circuit is copyrighten. not for commercial use of
any kind. May not be reproduced in any media existing now or to
exist in the future. For one-time only personal use only.
Protected by International Copyright laws.
green
100 ohm
hum
balance
to all tube heaters
green
The Tone Frenzy Amp
1 meg
47 pf
110k
220k
.01
500k
22 pf
150 pf
1M
switch
1.5k
1.1 meg
1.1 meg
22 pf
470k
2.2k
Ground
100 mfd
mid
1.8k
.003
22 mfd
25k
+
+
Bass
+
2
110k
.022
Treble
.1
47k
33k
500 pf
330k
1.8k
22 mfd
470K
100K POT
yellow
250k treble and bass
B+
reverb control
blu
.001
100K
.003
grn
1+6
V4A
220K
2+7
reverb
red
3+8
blk
springs
680K
2.2K
22 MFD
12AT7 parallel
reverb transformer
+
.1
1.5K
22 MFD
B+1
4100 to 4200 ohm
primary resistance
for 6L6 tube
The Tone Frenzy Amp
110k
220k
.01
500k
1M
switch
820 ohm
(bias?)
mid
1.8k
.003
22 mfd
Ground
25k
1.8k
22 mfd
470K
green
white
rectifier tube
primary
5 Volt
250k treble and bass
5V4
recitfier tube
filament
high volt B+
center
tap
red
1+6
rectifier tube
green
to all tube heaters
standby
10W
1W
B+3
B+4
22k
4.7k
1W
red
22
22
B+5
2.2K
DANGER
C
HIGH
VOLTAGE
Copyright
reverb transformer
1.5K
22 MFD
22
Drawing By Dan Torres
CAUTION
300 - 400
Dan Torres 2000
This circuit is copyrighten. not for commercial use of
any kind. May not be reproduced in any media existing now or to
exist in the future. For one-time only personal use only.
Protected by International Copyright laws.
B+2
22 MFD
1W
22
DANGER
springs
VOLTS
12AT7 parallel
47
blk
680K
100k
all in mfd and 450V 47
Ground
V4A
220K
reverb
3+8
pilot
light
to all tube heaters
B+2
1k
B+
100K
.003
grn
2+7
B+1
10 ohm
B+3
22 mfd
Bias?
470 ohm?
2
4
green
200 ohm
hum
balance
.1
600V
blu
.001
red/yellow
secondary
red
TH-270DX
8
6
reverb control
rectifier
output
yellow
6.3 V olt
power
switch
power transformer
3A
fuse
22 mfd
Torres optional
250k reverb pot
100K POT
yellow
black
1 ohm
+
100 mfd
+
+
+
2.2k
B+2
screen grid
filament is pins 2 and 7
470k
22 pf
Bass
4
8
1 ohm
1.5k
1.1 meg
1.1 meg
TH-125E output transformer
1.5k
22 pf
+
2
110k
.022
Treble
.1
6L6
3
5
500 pf
330k
47k
33k
47k
12AT7 parallel
.02
250k
B+4
47 pf
B+5
.1
B+3
B+4
1 meg
4 or 8 ohms
Drawing By Dan Torres
DANGER
CAUTION
Copyright
300 - 400
VOLTS
C
DANGER
HIGH
VOLTAGE
Dan Torres 2001
This circuit is copyrighten. not for commercial use of
any kind. May not be reproduced in any media existing now or to
exist in the future. For one-time only personal use only.
Protected by International Copyright laws.
front of the amp (where the controls go)
Parts ID legend
M = meg (as in 1 M)
K = 1000 ohms as in 100k
W1 = 1 watt
W2 = 2 watt
W5 = 5 watt
No ID on resistors = 1/2 watt
Tone Frenzy Amp Layout
MFD = microfarad
PFD = pico farad capacitor
size or capitalization of parts labels has no meaning
all small value capacitors are rated for 400 V or more
switch
switch
ground
ground
hot
Switching Jack
Switching Jack
22 mfd 450V
Torres Freeform 'board
22 mfd
22 mfd
22
47
mfd
450V
330k
470k
22 pf
B+4
4.7k .003
470k
B+3
.001
22k
W1
500 pf
.01
.033
220k
100k
.1 mfd
680k
100k
10 watt
.0
2
100k
B+2
10 ohm
FIL
5
6
7
7
6
3
2
1
1
7
2
6
3
4
8
FIL
8
FIL
FIL
FIL
8
1
7
2
6
3
FIL
1.8k
22 mfd
1 meg
k
K
47
1 ohm W2
B+1
1.5k
B+4
.02
2.2k
3.3k
0
10
mfd
450V
470 1k W1
22 ohm
mfd
B+3
100V 5W
10
0k
mfd
450V
100k W1
47
B+5
1.8k
B+4
B+2
820 ohm
22 mfd
450V
22 mfd 450V
8
7
1
1
6
2
2
3
3
FIL
8
FIL
.1
m
fd
hot
Drawing By Dan Torres
DANGER
CAUTION
Copyright
300 - 400
VOLTS
C
DANGER
HIGH
VOLTAGE
Dan Torres 2001
This circuit is copyrighten. not for commercial use of
any kind. May not be reproduced in any media existing now or to
exist in the future. For one-time only personal use only.
Protected by International Copyright laws.
front of the amp (where the controls go)
Parts ID legend
M = meg (as in 1 M)
K = 1000 ohms as in 100k
W1 = 1 watt
W2 = 2 watt
W5 = 5 watt
No ID on resistors = 1/2 watt
Tone Frenzy Amp Layout
Black Ground wires
MFD = microfarad
PFD = pico farad capacitor
size or capitalization of parts labels has no meaning
all small value capacitors are rated for 400 V or more
22 mfd
mfd
450V
330k
470k
22 pf
B+4
4.7k .003
470k
B+3
.001
22k
W1
500 pf
.01
.033
220k
100k
.1 mfd
680k
100k
10 watt
.0
2
100k
B+2
10 ohm
FIL
5
6
7
7
6
3
2
1
1
7
2
6
3
4
8
FIL
8
FIL
FIL
FIL
8
1
7
2
6
3
FIL
1.8k
22 mfd
1 meg
k
K
47
1 ohm W2
B+1
1.5k
B+4
.02
2.2k
3.3k
0
10
100k W1
47
470 1k W1
22 ohm
mfd
B+3
100V 5W
10
0k
22
B+5
1.8k
B+4
820 ohm
22 mfd
450V
22 mfd 450V
22 mfd
B+2
mfd
450V
Switching Jack
Switching Jack
22 mfd 450V
Torres Freeform 'board
mfd
450V
ground
hot
black to star ground at input jack
black to power supply ground at transformer
47
switch
switch
ground
8
7
1
1
6
2
3
3
FIL
8
FIL
2
.1
m
fd
hot
Drawing By Dan Torres
DANGER
CAUTION
Copyright
300 - 400
VOLTS
C
DANGER
HIGH
VOLTAGE
Dan Torres 2001
This circuit is copyrighten. not for commercial use of
any kind. May not be reproduced in any media existing now or to
exist in the future. For one-time only personal use only.
Protected by International Copyright laws.
front of the amp (where the controls go)
Parts ID legend
Tone Frenzy Amp Layout
M = meg (as in 1 M)
K = 1000 ohms as in 100k
W1 = 1 watt
W2 = 2 watt
W5 = 5 watt
No ID on resistors = 1/2 watt
MFD = microfarad
PFD = pico farad capacitor
size or capitalization of parts labels has no meaning
all small value capacitors are rated for 400 V or more
switch
switch
ground
ground
hot
Switching Jack
Switching Jack
22 mfd 450V
Torres Freeform 'board
22 mfd
22 mfd
22
47
mfd
450V
470
22 ohm
mfd
100V 5W
B+3
K
47
1 ohm W2
B+1
330k
470k
22 pf
B+4
4.7k .003
470k
.0
2
.001
B+3
500 pf
220k
100k
10 ohm
5
6
7
7
3
4
8
6L6
3
2
1
FIL
V4 1 & 6
8
6
1
7
2
6
FIL
3
1
7
2
6
8
7
1
3
1
2
3
V2 1 & 6
12AT7
reverb trans blue wire
Blue wire from output tranformer
8
6
2
FIL
12AX7
V1-1
FIL
FIL
8
FIL
12AT7
.1 mfd
V1-6
V3-1
V3-6
FIL
.01
.033
680k
100k
10 watt
22k
W1
100k
B+2
1.8k
22 mfd
1 meg
B+4
.02
2.2k
3.3k
0k
10
mfd
450V
1.5k
10
0k
mfd
450V
100k W1
47
1k W1
B+5
1.8k
B+4
B+2
820 ohm
22 mfd
450V
22 mfd 450V
FIL
12AX7
.1
m
fd
hot
Drawing By Dan Torres
DANGER
CAUTION
Copyright
300 - 400
VOLTS
C
DANGER
HIGH
VOLTAGE
Dan Torres 2001
This circuit is copyrighten. not for commercial use of
any kind. May not be reproduced in any media existing now or to
exist in the future. For one-time only personal use only.
Protected by International Copyright laws.
front of the amp (where the controls go)
Parts ID legend
M = meg (as in 1 M)
K = 1000 ohms as in 100k
W1 = 1 watt
W2 = 2 watt
W5 = 5 watt
No ID on resistors = 1/2 watt
Tone Frenzy Amp Layout
MFD = microfarad
PFD = pico farad capacitor
size or capitalization of parts labels has no meaning
all small value capacitors are rated for 400 V or more
switch
switch
ground
ground
hot
under the circuit board
Switching Jack
Switching Jack
under the circuit board
Torres Freeform 'board
V4 pin 3 & 8
22 mfd
22 mfd 450V
V3-3 green
22 mfd
22
47
mfd
450V
4.7k .003
470k
B+3
green
V4 pin 3 & 8
green
6
7
6L6 pin 8
7
8
6L6
3
2
1
1
7
2
6
FIL
8
1
2
.01
.033
.1
m
fd
220k
100k
.1 mfd
V1-8 green
pin 3 & 8
green
V3-3 green
7
8
7
1
6
8
1
6
2
3
3
2
FIL
FIL
12AX7
FIL
FILV2
3
FIL
12AT7
500 pf
FIL
3
4
.001
22k
W1
V3 pin 8 green
8
6
.0
2
100k
FIL
5
22 mfd
680k
100k
10 ohm
1.8k
1 meg
B+4
B+2
10 watt
2.2k
330k
470k
22 pf
k
K
47
1 ohm W2
B+1
1.5k
B+4
.02
B+5
3.3k
0
10
mfd
450V
470 1k W1
22 ohm
mfd
B+3
100V 5W
10
0k
mfd
450V
100k W1
47
820 ohm
22 mfd
450V
V2 pin 3 & 8 grreen
1.8k
B+4
B+2
22 mfd 450V
12AT7
V1-3 green
12AX7
hot
Drawing By Dan Torres
DANGER
CAUTION
C
Copyright
300 - 400
VOLTS
Parts ID legend
Tone Frenzy Amp Layout
M = meg (as in 1 M)
K = 1000 ohms as in 100k
W1 = 1 watt
W2 = 2 watt
W5 = 5 watt
No ID on resistors = 1/2 watt
pot ground bus - black wire
reverb 100k
master 250k
midrange 25k
22 mfd
820 ohm
22 mfd
450V
1.5k
450V
h ite
B+4
470k
B+3
.0
2
22k
W1
500 pf
.001
.01
.033
22 mfd
.1
m
fd
220k
100k
100k
B+2
1.8k
1 meg
0k
K
47
4.7k .003
.1 mfd
680k
100k
10 watt
1.1 meg
2.2k
330k
Tre
b
B+4
.02
1 ohm W2
B+1
470k
22 pf
B+3
Switching Jack
B+5
3.3k
10
100k W1
mfd
450V
470
22 ohm
mfd
100V 5W
hot
hot
1.1 meg
22 mfd 450V
1.8k
B+4
10
0k
22
mfd
ground
ground
V3-2
22 mfd
B+2
1k W1
volume
Switching Jack
22 mfd 450V blue
reverb
switch
switch
gre
en
Torres Freeform 'board
47
treble 250k
bass 250k
le W
MFD = microfarad
PFD = pico farad capacitor
size or capitalization of parts labels has no meaning
all small value capacitors are rated for 400 V or more
mfd
450V
HIGH
VOLTAGE
This circuit is copyrighten. not for commercial use of
any kind. May not be reproduced in any media existing now or to
exist in the future. For one-time only personal use only.
Protected by International Copyright laws.
front of the amp (where the controls go)
47
DANGER
Dan Torres 2001
10 ohm
V1-7
1.5k
FIL
5
6
7
8
6L6
2
1
1
7
2
6
3
4
3
8
6
7
FIL
V4 - 2 & 7
shielded
8
d
de
iel
sh
1
7
V3-2 & 7
FIL
v3 - 7
reverb return RCA jack
220k
7
1
1
2
33k
3
3
V1-2
FIL
12AT7
shielded
8
6
2
FIL
12AX7
FIL
47k
8
6
2
3
FIL
12AT7
FIL
12AX7
shielded
Drawing By Dan Torres
DANGER
CAUTION
Copyright
300 - 400
VOLTS
C
DANGER
HIGH
VOLTAGE
Dan Torres 2001
This circuit is copyrighten. not for commercial use of
any kind. May not be reproduced in any media existing now or to
exist in the future. For one-time only personal use only.
Protected by International Copyright laws.
front of the amp (where the controls go)
Parts ID legend
M = meg (as in 1 M)
K = 1000 ohms as in 100k
W1 = 1 watt
W2 = 2 watt
W5 = 5 watt
No ID on resistors = 1/2 watt
MFD = microfarad
PFD = pico farad capacitor
size or capitalization of parts labels has no meaning
all small value capacitors are rated for 400 V or more
Tone Frenzy Amp Layout
power supply connections
switch
switch
ground
ground
hot
Switching Jack
Switching Jack
22 mfd 450V
Torres Freeform 'board
22 mfd
22 mfd
820 ohm
22 mfd
450V
1.5k
22
47
mfd
450V
red
red
B+1
B+4
4.7k .003
470k
B+3
.0
2
.001
22k
W1
500 pf
.01
.033
220k
100k
100k
B+2
.1 mfd
680k
100k
10 watt
10 ohm
rectifier tube
FIL
5
6
5
7
4
5V4
0o
47
8
hm
5
W
6
8
6L6
3
1
.1 mfd
2
1
FIL
8
6
1
7
2
6
3
4
3
2
7
7
FIL
1
7
2
6
3
metal film
yellow
yellow
5V filament from power transformer
green from reverb trans
reverb send
brown wire from output transformer
red wire is NOT USED at all
red wire from reverb transformer
8
7
1
black (ground) from reverb trans
8
1
6
2
2
3
3
FIL
FIL
12AX7
FIL
FIL
8
FIL
12AT7
1.8k
22 mfd
1 meg
0k
K
47
1 ohm W2
2.2k
330k
470k
22 pf
B+4
.02
B+5
3.3k
10
mfd
450V
470 1k W1
22 ohm
mfd
B+3
100V 5W
10
0k
mfd
450V
hi voltage secondary
from power transformer
100k W1
47
22 mfd 450V
1.8k
B+4
B+2
12AT7
12AX7
.1
m
fd
hot