US: SAN FRANCISCO
Jason Victor Serinus
IT'S 11AM ON October 1, and event
organizer Variac's (Mark Cronander)
"Official Welcome" to the fifth annual
Burning Amp Festival for do-it-yourself
audio designers and builders (www.
burningamp.org) is half an hour overdue.
I had already been unofficially welcomed
when I wandered into a large
room, commanded in part by Wood
Artistry's latest execution of Siegfried
Linkwitz's Orion loudspeakers,
Zenwood Audio's far larger and
eye-catching Lowthers, and Auraliti's
PK90 USB file player. As an unforgettable
recording of Viennese waltzes
punctuated by aggressive birdcalls
played far too loudly on the Zenwoods,
and friends old and new chatted at even
higher volume, volunteers lugged roll
after roll of quilted padding into the
room to optimize its acoustics.
For a moment, I wondered if I'd
wandered into a makeshift asylum.
No, this was the country's
premier annual DIY gathering,
where equipment builders let
their imaginations run free and
hope that what they come up
with makes the grade. Even if it
doesn't, the sheer joy of creation
is ample reward.
This year, Burning Amp was
attended by a record-breaking
200 DIYers, most of whom
also participate in the diyAudio.
com forum.They arrived at San
Francisco's Fort Mason Center from
as far away as India, Serbia, the UK-even
Minnesota. ...... Such is the
atmosphere of camaraderie that makes
Burning Amp and the diyAudio.com
forum unique.
Every room on the second floor was
fllled with equipment displays, both
active and silent. Exhibitors rotated
systems, sometimes adding just-arrived
components they'd never heard. Exhibits
were even squeezed into "The Big
Room," where DIY hero and mentor
Nelson Pass, of Pass Labs, addressed
a standing-room-only crowd about his
latest experimental circuits, Douglas
Self spoke about active crossovers, and
a heaven's helping of audio parts was
raffled off. Against one wall, Linear
Systems touted their second-source
replacement parts for highly prized
JFET transistors and other essential
devices no longer produced by their
original manufacturers. Elsewhere,
several DIY magazines were on display,
and refreshments and snacks were
available. Except during the scheduled
talks, schmoozing was ubiquitous.
This year, Nelson Pass, his son Colin,
Pass Labs analog-and-digital designer
Wayne Colburn, and many volunteers
converted one room into the Pass Pub.
Although I saw no liquid refreshment,
its sonic equivalent included Pass's slot-loaded,
open-baffle loudspeakers and
two of his most interesting amplifier
designs. One, dubbed The Beast with a
Thousand JFETs, is a monoblock design
whose 1176 little JFETs are perfectly
positioned on four boards, each of which
contains 14 rows of 21 ranks. Nelson
calls the JFETs "those unobtainable little
Toshiba parts that give bragging rights
to Pass Labs and A yre, etc. They are the
best MC phono input devices, and now
I am using them also as output
transistors. Why? Because I can."
With excellent results, I might
add.
Nelson Pass's other amp, a
Static Induction Transistor (SIT)
design that will soon be the
subject of a white paper, was formally
unveiled at the 2011 Rocky
Mountain Audio Fest, in October:
"In the '70s, SITs were called
VFETs," Pass explained by e-mail.
"Yamaha and Sony made them
for a while. I had some made for
me in silicon carbide (SiC), and
First Watt is in the process of
producing a mono and stereo amp
with them. They are particularly special
in that their curve is like that of a triode,
where other FETs look like pentodes.
The amps feature only the single transistor
as the gain device, operated single-ended
class-A with no output transformer,
no feedback, and no degeneration. It's
about as raw as you can possibly get, and
they sound fantastic."
True to the DIY spirit, even the
Pass Pub included equipment made by
others. When an awed Terry Gesualdo,
of Santa Rosa, arrived with his preamp,
he was shocked when Pass greeted him
with, "We'll squeeze you in." Gesualdo,
who got hooked on DIY at age 18,
when he built 18" subwoofers to augment
his Magnepans, was one of many
still-youthful DIYers at Burning Amp
who began tinkering with components
in their teens, and decades later are still
building and modifying gear.
In another room I encountered Dave
Meyers, of Minnesota. On weekdays,
Meyers works as a QA tech at Audio
Research. His job is to power
up units for the first time, then
burn them in. "We breathe life
into amps," he quipped, before
showing me his USB HDDAC.
"My whole reason for
doing this was to learn about
digital audio and see what
worked."
Some designs worked far less
well than others. As I spoke
with software engineer Ti Kan,
of Sunnyvale, California, whose
AMB Laboratories sells to
DIYers circuit boards, parts, and
headphone amps (in collaboration
with Bryan Levin of Sercona
Audio), an unrelated adjacent
system was playing in the background.
After a while, I was pretty certain that
I was hearing the voice of the young
Joan Baez. But without any top or bottom
to the sound, I couldn't be sure.
Some of the best sounds came from
Don Naples' Linkwitz-designed Wood
Artistry speakers, fed by Auraliti's
entry-level PK90-USB file player with
new optional power supply, a SOtM
USB DAC 200 from Korea, a proto-
type Auraliti line preamp, a six-channel
ATI amplifier, and nondescript cables.
Auraliti's long-awaited, top-of-the-line
L-1000 file player, designed by Demian
Martin and Ray Burnham, will be out
by end of October. Siegfried Linkwitz
told me that he's now using specially
modified SEAS 10" woofers in his
speakers, and that the SEAS drive-units,
modified for dipole application, will
soon be made generally available-yet
another boon for DIY speaker builders.
Ultimately, the Burning Amp Festival
is about being there, in whatever ways
you wish, and showing off equipment
that you've built to your heart's desire.
California residents Glen Egan (Oakley)
and Scott Mallet (Coto de Caza) typified
the spirit of the occasion when they
told me, "We first got together and
connected equipment 50 seconds ago.
Of course, we haven't played it yet. We
hope the smoke stays in." Happily, the
climactic bonfire never happened.
) ......
