Dan D`Agostino - The Absolute Sound`s Illustrated History of High

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Dan D’Agostino
Krell Industries and Dan D’Agostino Master Audio Systems
BY C H R I S M A RT E N S
Dan
Left:
Dan D’Agostino
Master Audio Systems
Momentum Integrated
Amplifier.
D’Agostino has had high-end audio in his blood from
a very young age, having been influenced early on by
his father’s interest in music and hi-fi (D’Agostino
fondly recalls his dad’s system, which consisted of assembled-from-plans
Klipschorns and a small Lafayette Radio tube amplifier—a system the young
D’Agostino thought sounded “really amazing”). Later, D’Agostino began
spending time at a neighborhood hi-fi store and, at 16, became an employee
of the shop, launching what has thus far proven to be a lifelong career in
high-end audio. Dan D’Agostino enjoys the distinction of having founded
not one but two top-tier audio electronics manufacturing companies: Krell
Industries and Dan D’Agostino Master Audio Systems, both of which have
produced state-of-the-art contenders.
As the high-end audio movement gradually gathered momentum in the
1970s, D’Agostino closely followed products that were garnering critical
acclaim. One such product was the Mark Levinson ML-2, a comparatively
expensive, 25Wpc, Class A power amplifier. While acknowledging the
Levinson amplifier’s sonic appeal, D’Agostino considered its power output
underwhelming, leading him to decide to “try to make one that was 100
watts” per channel. Out of that decision Krell Industries was born.
Krell’s first product was the KSA-100, a Class A 100Wpc channel stereo
power amplifier, which debuted at a trade show early in 1980 (at the time only
three prototypes of the amp existed). Coming in, D’Agostino’s hope was that
his fledgling firm might eventually grow to a point where it would ship as
many as ten KSA-100s per month. However, initial reactions to the amplifier
were so positive that Krell left the show with orders for fifty amplifiers, with
more to come—essentially going from being a start-up to becoming a fullfledged company almost overnight. What ensued was a cyclic process of
designing, selling, and building one new model after another as the company
continued to expand. But over time D’Agostino found that Krell’s growthfirst mentality had in certain respects drained some of the fun and satisfaction
out of building top-tier audio amplifiers.
Then, in 2009, everything changed. Krell had taken on a minority investor
without grasping that the associated investment contract gave the investor
the power to force top-level staffing changes. Within a matter of months,
D’Agostino’s position was terminated and he was compelled to leave a firm
he had spent the better part of 30 years developing. Naturally, D’Agostino
found this turn of events distressing and disappointing, but rather than
give himself over to bitterness, he decided to begin anew by founding Dan
D’Agostino Master Audio Systems, a company deliberately guided by a
somewhat different ethos than Krell.
Where Krell had been strongly growth-oriented, Dan D’Agostino Master
Audio Systems is a business whose primary mission involves exploring the
upper limits of performance and aesthetics for premium-class high-end audio
electronics—electronics that, for now, are best represented by the firm’s lovely
Momentum series amplifiers. Interestingly, D’Agostino describes his new firm
as the sort of company he initially imagined Krell might become, where the
designer derives satisfaction from creating technically advanced amplification
products that are profoundly musical and artful in every sense of that term.
Dan D’Agostino
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Dan D’Agostino
The Interview
How did you get your start in high-end audio? What first attracted you to the field?
Well, music was a big deal for me as a kid and my dad was really interested in it.
He built a pair of Klipschorns from a kit. He was always listening to different
kinds of music and got a little tube amplifier from Lafayette Radio. At the
time, the thing sounded really amazing. That really got me into listening.
There was an audio store a few blocks from where I lived and (the owner)
got me excited about audio; we listened to his big record collection there.
When I was 16, he gave me a job, cleaning up, dusting, and helping out, which
was cool.
When I got out of school I wanted to work in audio and I started looking
for opportunities. At the time, everybody was buzzing about the (Mark
Levinson) ML-2 pure Class A amplifier that was 25 watts per channel. I
looked at the marketplace and decided that that
25-watt amplifier was not what I really liked,
so I decided to try to make one that produced
100Wpc. That amp became the Krell KSA-100.
That’s how I got started in the business.
and satellite speaker system for him. It was called the Point 3. Burt financed
(the design) and sold the Point 3s all over the country, so that was how I went
right from working in a store to designing equipment.
How and when was Krell founded?
I had put a little money away—I was in New York—and I decided that I was
going start this company. I had met my then-friend Rondi Holling and we
started Krell Industries in 1979, with our first showing in 1980. Our initial
product was the KSA-100 amplifier. She was going to sell it, and I was going
to design it.
When the company first began, what were your goals for its products?
Here’s what our plan was. We figured if we sold
ten of those (KSA-100 amplifiers) a month
worldwide, we could live OK and design a
preamp and a couple of other products and just
have kind of a decent living and not have any
worries.
Actually none of that worked out because
when we went to the show we sold something
like fifty amplifiers! And when we got back from
that show I didn’t even know where to start. I
had to actually produce products that weren’t
prototypes!
We spent a whole year getting out the fifty
units we had sold and we collected some more
orders, and it became kind of like a treadmill
after that, doing more products. I’d go out on
sales trips and come back with orders. Then,
most of the time, I would deliver the finished
products and collect payment for them, because
we needed money. It was kind of hand-to-mouth.
Krell never turned out to be the kind of small, hobby-oriented shop and
fun place that I thought it was going to be. Before I knew it, I had probably
eight or 10 employees and just kept on putting products out, so there was
never a time—once the company got a foothold—that we ever got to relax
with it. I mean, it just turned into a company organically and kept on growing
until we were inundated.
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What was the first hi-fi system you remember owning?
I had a system with some Williamson tube
amps that I built from scrap components, and
speakers put together from Philips drivers
from Olson Radio. I can’t recall what turntable
I had, but it wasn’t anything special, though it
had a Shure cartridge. And that was my homebrew system. It played music and I loved it; I
thought it was the best thing in the whole world.
What types of music do you enjoy most?
I love listening to great jazz; I can’t get enough
of it. And I sneak in some rock. Because I’m
a child of the 60s, I have to have some rock ’n’ roll in my life. I like some
classical music, but it’s not my mainstay, though I do enjoy a few operas, and I
love Mozart and Chopin. Those kinds of things are all enjoyable. But mostly
I listen to jazz.
How did you make the transition from the retail side of audio to becoming a full-fledged
equipment manufacturer?
Well, the owner of the store I worked in and I had a disagreement and I left.
After that, I met this guy in New York named Burt Cullen who had an audio
company called Great White Whale, and he asked me to design a subwoofer
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Dan D’Agostino
You are best known for your solid-state amplifiers, but what is your take on the age-old tubes
vs. transistors debate? Have you experimented with tube-based designs?
I haven’t really experimented much with tube designs. I have compared
(tube electronics) with my stuff and when I did my new company (Dan
D’Agostino Master Audio Systems) I really worked at making a solid-state
amplifier, not one that mimicked tubes, but that actually sounded better and
that didn’t exhibit the sonic anomalies that some solid-state amplifiers do. I
worked on making something really linear that wasn’t fatiguing, and didn’t get
harsh or bright. That’s something I’ve worked at and am constantly working at.
What led to your transition from Krell and to the creation of Dan D’Agostino Master
Audio Systems?
I was virtually thrown out of Krell by a minority investor who had the power
to do that, though we didn’t realize it (at the time the investment was made). We
took in the investor so that we could grow the company horizontally and vertically at the same time. That was never, in my opinion, his plan and he was able to
terminate my job there within two months after he got involved in the company.
Between my ex-wife Rondi and myself, we own 60 percent of Krell—
so it’s kind of a bitter thing. The matter never got to court and may
never get resolved, but after six or eight months I said, “I’m just going
to start another company; I’m going to do something that’s unique and
different and better and more beautiful than anything I’ve ever done.”
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Does Dan D’Agostino Master Audio Systems have different goals and a different mission
than Krell did? If so, how does it differ?
Yes. Krell always wanted to grow, always wanted to push that envelope, and
so we went high, and then we went low, and we went into different things like
home theater—things like that.
Dan D’Agostino Master Audio Systems does not want to do that. We
primarily want to stay in the two-channel domain, focusing on products that
offer truly exemplary performance. We are not into making compromises in
what we have designed, so it’s not our goal to go down to the two- or threethousand dollar price range and expand horizontally.
Top: KSA-100
stereo amplifier.
Middle: KSA250, interior view.
Bottom: Dan
D’Agostino at the
Krell factory.
Is the new company more like the way you had imagined Krell might have been in the
beginning?
Yeah. I’m actually having more fun here than I had at Krell. When I first
started Krell, I was having this kind of fun, too, but then it got to be too much
of a business.
Dan D’Agostino Master Audio Systems is a pretty solid business, too, but
we’re much more laid-back and we’re only interested in the finest products we
can create. And I’m doing a lot of the work myself—all of the board layouts
and mechanical designs, and I’m having a ball with that.
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What is your design process like? What is your approach to design?
At Krell, I would conceive a product and its performance envelope and then
I would put a package around it—kind of like having the function dictate the
form.
But with the Momentum I really wanted to make something that no one
had ever built before; I wanted to cross the lines between watches and cars and
audio equipment—things that could be beautiful, yet functional. To that end,
I worked with forms until I got a shape that I liked and then I started working
on the size. I don’t know if you’ve ever heard the term “God’s numbers,” but
the dimensions of the Momentum amplifier are really within that realm. So
it’s very pleasing when you look at it in real life.
This amplifier represents an effort to make something beautiful (and
moderately sized) that could have real performance, which wasn’t going to
happen unless I got that package designed first. Then, I realized how small
the inside was and how much power I wanted it to have and that’s when the
designing really got difficult.
If you look inside the Momentum amplifier, it’s got an 1800VA transformer,
30-some output devices, a big power supply, four different regulators,
protection circuits, and meters, all in a box that’s 12" x 4" x 18". And that
thing really does put out—a little over 400 watts into 8 ohms, doubles down
to 2 ohms—and it’s got huge reserves of power.
It also uses a heat control system made of copper, which allowed me to
eliminate big fins on the outside. The copper works very well in storing energy,
meaning there’s hardly any difference between the temperature of the output
devices and the heatsink, if any at all. This gives the amp terrific stability.
The circuits I use in the Momentum are totally different, too. The whole
design was based on the idea that it was going to sound musical. I listened
with a lot of friends and I compared the amp to things I’d done in the past,
until I got it to where it was head and shoulders above any of my older work.
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Is the industrial design of the Momentum entirely your own work?
Totally. When prospective customers first saw the Momentum at shows,
sitting on its little stand on the floor, they said, “Is this the mock-up? This is
not the real amplifier, is it?” because it was so small. They all expected it to
be a giant.
Here’s an admittedly loaded question: When you design, are you driven more by the love of
music, love of technology in the service of music, or a bit of both?
It is a little bit of both. Some of the design I do is because it’s technically really
cool to do. But a lot of the circuits that I have been drawn to also sound really
good. I’ve had a lot of experience with different kinds of circuitry and their
sounds, so I know certain things that I do are going to sound good.
What sonic qualities do you hope listeners will associate with your designs?
First, I’m after an anti-fatiguing sound overall—something that relaxes you.
I also consider low-level detail, information retrieval, and wide, deep 3-D
soundstage to be mandatory for my designs now. I want my amps to make a
big holographic presentation. Along with that, I want all of the little nuances
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Top: Dan with
Krell’s Dean
Roumanis (left)
and an early Krell
distributor.
Middle: Inside the
KSA-100.
Bottom: Dan
working on a
Momentum
prototype.
ICONIC PRODUCT
Momentum Monoblock Power Amplifier
In recent conversations with Dan D’Agostino, The Absolute Sound asked,
“If you had to name one iconic Dan D’Agostino product that best represents your core technical and musical values, what product would that
be?”
Without hesitation D’Agostino replied, “I think without question it
would be the Dan D’Agostino Master Audio Systems Momentum Monoblock amplifier. It achieved all of the things that I tried to do in one small
unit.” But to really understand the amplifier’s full appeal it is first necessary to understand what D’Agostino means by the phrase, “all of the
things I tried to do.”
While many of D’Agostino’s amplifiers are regarded as fine pieces of
industrial design, the Momentum was his first product conceived from
the outset to be a true work of art. Profoundly influenced by D’Agostino’s
deep fondness for fine watches and automobiles (among other things),
the Momentum exudes an unmistakably elegant yet understated sense
of physical presence, with graceful proportions and gleaming, precisionmachined, billet-aluminum and solid-copper chassis panels. The pièce de
résistance, however, is the amplifier’s upward-angled, Jules Verne-esque,
machined aluminum “porthole,” which houses a softly illuminated steamgauge-style power-output meter bearing Dan D’Agostino’s signature.
So striking
design
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p y is thet o
d that,
a yat trade shows, the Momentum has been
known to attract groups of admirers who gather around the amplifier as
if viewing it on display in an art gallery.
But the artistry doesn’t end with the amplifier’s physical appearance,
as the Momentum’s sonic prowess is more than a match for its visual
appeal. The amplifier is a low-feedback, high-power, high-current design
that puts out a conservatively rated 300Wpc at 8 ohms, 600Wpc at 4
ohms, and a whopping 1200Wpc at 2 ohms, while exhibiting wide bandwidth (1Hz–200kHz), good (but not obsessively good) distortion specifications, and the ability to reproduce square-waves with no discernible ringing or overshoot. The amp uses extremely high-quality parts throughout,
including—in Dan D’Agostino’s own words—“an 1800VA transformer,
30-some output devices, a big power supply, four different regulators,
protection circuits, and meters—all in a box that’s 12 inches by 4 inches by
18 inches.”
The upshot is that the Momentum has quickly earned a reputation as
the most aesthetically pleasing, best built, most sonically revealing, and
by far most effortlessly musical power amplifier that Dan D’Agostino has
ever created. The amplifier has received critical acclaim from numerous
audio journalists, but perhaps an even more telling indicator of its balanced excellence is the fact that makers of high-resolution loudspeaker
systems often request (or require) Momentum series amplifiers for use in
their trade show demonstration rooms—where making a great first impression, musically speaking, is of paramount importance.
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that are way down at low, low levels reproduced so that you can hear them
even at low levels. It’s always been my goal to make amplifiers whose operation
remains consistent, even when loudspeaker impedances fluctuate.
When was Dan D’Agostino Master Audio Systems founded?
I think it was 2010 or maybe 2009, though I don’t think we had a product
until 2011.
What is your view of the emerging high-resolution digital audio movement and how does
your company fit into that movement?
I think that that’s the savior of our industry if we can get a good, solid reference
company to go out there and make people want to use hi-res downloads. I
think it’s going to drive people back into the stores.
It doesn’t help when the press talks about competing digital music systems,
such as the new Apple Music or Tidal systems, stating that they offer “higher
resolution,” but without explaining that they are superior sounding. I suspect the
people writing those articles are not knowledgeable enough to understand the
difference sonically that something like Tidal represents to us.
When evaluating amplifier designs, do you have a preference for using analog or digital
source components and if so, why?
Mostly I use digital because I have a bunch of recordings in digital format that
sound really good and that I use as references. I have them on a server and
so it’s easy to switch between different tracks and I can get a real reading for
how that amplifier sounds and for its strong points, right away. I can play ten
or twelve tunes and I’ve got it.
Consistency is a wonderful part of digital audio’s appeal, but if you have
a really good DAC like a dCS Vivaldi or a big MSB, you’re going to get such
great resolution and musicality that it’s a pleasure to listen to in every aspect.
Where do you feel high-end audio is headed in the next decade?
In my opinion, I think it’s going to be more segmented, and more pushing
the envelope of high end in every realm, whether it’s tube or transistor. I
think people are just going to keep on pushing and pushing and pushing.
Maybe somebody will come up with a really good-sounding Class D amplifier
someday. It won’t be for me, but it would be for somebody else. [He chuckles.]
I’m really praying that people get the idea that music never goes away and that
listening to music on a mediocre system is never going to make you satisfied.
Maybe somebody will come up with a
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Because once you get the idea that you can sit in your chair and call up your
favorite tune—one that you liked when you were in high school (or searched
for online), and can play that song in hi-res on your system, I think that’s an
extraordinary thing.
What’s next for Dan D’Agostino Master Audio Systems?
We’re building a unit that will come out at the end of this summer (2015),
called the M-Life. It is our integrated amplifier with streaming audio and
Tidal built into it, and with its own app on iTunes and on Android. It comes
packaged with an iPod touch and an (Internet) Access Point so that you just
hook it up to a pair of speakers and get amazing sound. It’s a single-chassis
streamer/amp/DAC, but done at the highest level.
Then, at the beginning of next year (2016) I will have the new Helios amp
finished. It is a big power amplifier whose performance envelope is similar
to that of the huge Krell Master Reference Amplifier (from a decade ago),
but that sounds much better and is also much smaller—though it is still quite
heavy. It’s going to weigh between 750 and 800 pounds. It’s for people who
want big Momentums. The name Helios, by the way, is a Greek word that
means “power of the sun.” The amp applies some really different circuit concepts, which I’m not going to talk about too much, but it’s going to be a real
mind-blower when it comes out.
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Dan D’Agostino
impossible to drive. However,
Krell’s KSA-100 amplifier became
part of audio legend by consistently
delivering roughly 1000 watts (if
not more) into the Scintilla’s worstcase 0.8-ohm load.
Helios
The first Dan D’Agostino-designed
high-end audio product wasn’t an
amplifier; it was the Great White
Whale Point 3 satellite/subwoofer
loudspeaker system.
Dan D’Agostino Master Audio Systems’ upcoming Helios power amplifier is intended to address the desires of listeners who want, says Dan
D’Agostino, “a big Momentum.”
While the Helios will be smaller than
Krell’s absolutely massive 1000Wpc
Master Reference Amplifier circa
2006, it will offer comparable output
capabilities, is claimed to provide superior sound quality, and will weigh
between 750 and 800 pounds.
Deceptive Momentum
Krell
Dan D’Agostino has an established
history of producing large, physically imposing power amplifiers. So,
when D’Agostino first showed his
comparatively compact Momentum
amplifier to members of the audio
Although Dan D’Agostino is no
longer involved with Krell Industries, a company he founded nearly
30 years ago, he and his ex-wife
Rondi still own 60 percent of the
firm.
D’Agostino’s Debut
TECH FOCUS
Unflappable Output Power
In surveying Dan D’Agostino’s high-end amplifier designs over the years, it seems his
adjustable output-stage biasing circuit that made even higher-powered Class A amplifiers
overarching philosophy might be summed up in this aphorism: The only thing better than
feasible.
a great sounding low-output amplifier is an equally great sounding high-output amplifier.
Fourth, D’Agostino amplifiers have long been industry standard-setters in both external
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Through conversations with D’Agostino, it becomes apparent he believes that an amplifier
and internal build-quality, often coupled with innovative use of components and materials.
should never, by dint of insufficient output, dictate the listener’s choice of loudspeakers.
Unlike designers who seemingly take a prosaic, “parts is parts” approach to design, D’Agostino
Similarly, D’Agostino holds the conviction that high power output should never, ever be used as
has never been shy about specifying ultra-high-quality and ultra-tight-tolerance parts
an excuse for an amplifier that exhibits mediocre sound quality. But how do these beliefs play
throughout his designs, starting with chassis components and working inward to power
out in technical terms in D’Agostino amplifier designs?
supply components, PCBs (which D’Agostino often lays out by hand), resistors, capacitors, and
First, D’Agostino’s amps are extremely linear, wide-bandwidth designs. A good example
would be the Momentum Monoblock amplifier, whose stated frequency response is 1Hz–
semiconductors.
But D’Agostino also has a keen eye for simplicity and elegance in his designs, some of which
200kHz, +0dB/-1dB, or 20Hz–20kHz +/-0.1dB. Not surprisingly, the Momentum uses twenty-
involve creative use of materials. For example, he once developed an amplifier that used no
four 69MHz output transistors, reflecting the fact that, for D’Agostino, the quest for bandwidth
internal wiring whatsoever, where circuit boards used pin-connectors to attach directly to
and linearity never ends.
the amplifier’s outputs via gold-plated copper bars. Similarly, in the new Momentum amps,
Second, most D’Agostino models are typically fully balanced designs—an approach taken
D’Agostino eschews traditional cooling fins in favor of thick, smoothly finished solid copper
with an eye toward reducing noise (or increasing gain relative to a given level of noise) in order
sideplates that have clever, visually unobtrusive venturis machined into their edge surfaces,
to improve rendering of low-level sonic details. D’Agostino recently told The Absolute Sound,
thus creating a highly effective, passive, flow-through cooling system.
“I think I was the one who pioneered the use of balanced output designs in high-end audio. I’m
Finally, as D’Agostino has matured as a designer, his products have increasingly shown
not the first guy that did balanced circuits, because they were already prolific in the pro-audio
an emphasis on the elusive quality of musicality. To achieve this end, the latest D’Agostino
industry. But when I did the Krell Reference Standard Amplifier, which had balanced inputs,
amplifiers are low-feedback designs with abundant open-loop bandwidth and they forego,
and brought it to a show in 1985 or 1986, it was considered a big deal—a really big deal.”
apparently by design, the “nth” degree of (nearly immeasurable) low-distortion performance
Third, in pursuit of the often difficult-to-balance goals of high sonic purity and high power
output, D’Agostino has long been a proponent of “high-powered, clean amplifiers that operate
in mostly Class A mode.” He is also insists that his amplifiers provide exceptional current
in an effort to achieve superior sonic agility, nuance, and resolution in handling unpredictable
and constantly varying musical signals.
As D’Agostino says in our accompanying interview, “I really worked at making a solid-state
output capabilities, the better to handle low-impedance loudspeaker loads. Indeed, this
amplifier, not one that mimicked tubes, but that actually sounded better and that didn’t exhibit
pattern was established with D’Agostino’s very first amplifier, the Krell KSA-100—a 100W Class
the sonic anomalies that some solid-state amplifiers do. I worked on making something really
A design that became legendary for its ability to deliver enormous power into speakers with
linear that wasn’t fatiguing, and didn’t get harsh or bright. That’s something I’ve worked at and
impedances as low as 0.8 ohms! By the mid-1990s, D’Agostino was granted a patent for an
am constantly working at.”
Dan D’Agostino
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