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Thor Audio News
New Preamp Chassis !
Inside view (upside down) of
the bored 1" (25.4 mm)
thick Top Plate
(used in our TA-1000, TA-
2000, & TA-3000 preamps)
Black Diamond Racing
“Pucks” & “Cones”.
A one -piece “spun” bare
metal of a TPA-150 main/
bottom chassis.
The new preamp
chassis is basically bored
from solid blocks of pristine
aircraft-quality aluminum
and now features a massive
1" thick top plate!
In addition, the
sides of the chassis are now
a full 1/2" thick. All RCA
jacks in the back are recessed into oversized holes
counterbored from the outside showing the true thic kness of the outside wall.
We will continue to
use the Black Diamond
New Power Amp Chassis !
“Metal Spinning”
is a procedure that dates
back well over 100 years.
Surprisingly, most people in
the metal fabrication business these days have never
even heard of it!
While others may
have heard of it, there are
only a couple of dozen people in the entire US that can
"Pucks and Cones" combination (see picture) for stability and height underneath
all of our power amplifiers.
However, as a result of this re-design, the
preamp chassis is so massive and rigid that it will handle any sound-robbing
(preamp level) vibrations
with ease. Because it no
longer needs as much mechanical clamping/damping
of the bottom, we have removed the "pucks".
Note that we will
continue to use the pyramid
actually do it, and this is be-
cause it was handed down
from father to son!
This procedure
(soon to be seen in it’s entirety on our web site)
makes a one-piece round
chassis (see picture).
If you want a truly
round chassis, AND have it
be only one piece, this is the
cone feet as before.
Another added
benefit is that removal of the
pucks will also lower the
overall height of the preamp
from 5 1/2" to 4 3/4". This
lower height also makes it
useable with many more
audio racks.
Readers Note : Some of the
best news is that while these
chassis are much more expensive to produce, we will
not be increasing our retail
prices until next year!
only way to do it.
The chassis are so
structurally strong and inert
that they handle any soundrobbing vibrations with ease
and gives the best look we
have seen to our amp cha ssis. Even the TPA-30 and
the TPA-60 chassis will be
back-engineered to accommodate this new design!
Powder coated chassis
shown with the Electron-
Beam Laser -welded Top
Electron-Beam Laser -Welded Chassis !
A perfect marriage of “old and new” -
We start with a perfectly
“spun” chassis. (see above
picture)
Then, any welds
that are necessary are done
using the very latest in
“Space-Age” technology—
The Electron-Beam Laser
Welder.
This makes the
chassis itself (and especially
the electrical earth ground)
totally contiguous and gives
an invisible seem to the outside of the chassis.
Additionally, it is
so strong that it becomes
even harder than the metal
itself. This is why it can be
used for spacecrafts and the
like.
The invisible laser-weld on
the side of an amp chassis.
Volume 3, Issue 1
Black Diamond
Our Stock Tube Selection - How and Why
Page 1
Quite a few customers have called to ask us about
replacing the stock tubes with
NOS, etc.
While we don’t ask
not to replace our tubes, we
thought that an explanation of
how and why we use the tubes
we do would make our point.
Our importer receives
1000 tubes at a time. He then
measures each tube (both tri-
odes) for gain, noise, distortion,
microphonics, etc. He then
sends back up to 600 that do not
meet our criteria. Of the remaining 400 tubes, 300 go into
line stages, and the remaining
The TPA-150s are in Production !
These amps are
the result of a painstaking
process taking many years
to production. Like the rest
of our line, they reflect a noprice-point approach to circuit/component selection,
and are built using essentially a hard-wired point to
point design. This approach
retains all the sonic characteristics of any source, leaving their original signals in
100 best (lowest noise figures,
etc.) go into phono stages. We
pay quite a hefty price to have
this done for us, but it is more
than worth it.
Different tubes can be
used as an “equalizer” in systems. For example, they can help
to tone down a bright interconnect, or give more detail to a
dark pair of speakers. We always
suggest that the customer keep
the stock tubes in out component until at least 400 hours of
play. This will give you a good
starting point to begin experimenting. NOTE: We have had
many customers call us to tell us
that they went back to our original
tact. As a result of this design, the TPA-150 has a
startlingly clear presentation
of inner detail with a transparency that goes beyond
soundstaging and literally
enters your listening envi-
ronment!
The TPA-150 is
designed into a 20" round
chassis with careful thought
to every aspect of circuitry,
customer safety, and ease
tubes because they felt that in our
circuits they were the best overall
choice for timbre neutrality, tran-
sients, and detail.
Also, because of the
reveling nature of our components, we have had other customers call to tell us that our
preamp or amp revealed some
system weaknesses such as the
cabling, etc. We always suggest
that the purchase of more neutral cables, etc. is the way to
go—not to “Band-Aid” the prob-
lem by using different tubes.
Another reason to
keep our stock tubes is a matter
of soundstage depth and focus...
of use. All circuitry and
transformers are mounted
inside the chassis. Only the
tubes, fuses, bias pots and
meter are visible. The result
is a simple and extremely
elegant appearance.
All power and out-
put transformers in the TPA150 are custom wound to
our demanding specifications and are proprietary to
Thor Audio.
… We ask to “Use Reversed
Matched Tubes Only!” in both
TA-2000 and TA-3000 owner’s
manuals. The reason for this is
that the tubes’ physical layout is
a “mirror” image of the left and
right channels. This means that
triode 1 of the Left tube must
equal triode 2 of the Right tube
to keep the same gain for both
channels. This extra step is one
of the reasons for our depth!
Very few of the providers of
NOS tubes will give you the gain
of both triodes, let alone giving
you a reversed matched set.
However, this sort of mismatch
can result in as much as a loss of
ten feet in the soundstage!
TPA-150 Mono-Block
We are very
pleased to announce that
Black Diamond Racing has
designed stands specifically
for our power amps! Each
stand is a full 1 1/4" thick,
and is modeled after their
well received "The Shelf"
series. However, with the
many added benefits of it's
matching round shape,
these stands provides a
performance that has to be
Black Diamond Amp Stands
heard to be believed! Each
stand has three "Pyramid
Cones" and "Pucks", (see
picture) making the overall
height of the stand a little
over 3". Each stand has
three dimples on the top that
align with the three cone
feet on the bottom of the
amp. This alignment is used
to keep the heavy section of
the amp precisely lined up
with the stand's feet at the
optimum place for the best
weight distribution - and
therefore the best sound.
Besides being an obvious
visual match to the amp's
standard BDR feet and
round shape, many audible
benefits are immediately
heard. Most notably, they
are in the areas of focus, air,
transparency, soundstage,
timbre, attack/rise time, and
a deeper/tighter bass.
Amp Stands
(TPA-30 version shown)
Thor Audio
Thor Audio
315 Palamar Drive
Fairfield, CT 06432 USA
Phone: 203-373-9264
Fax: 203 -372-2202
Email: sales@thoraudio.com
You will hear the difference Immediately!
We’re on the Web at
www.thoraudio.com
ThorAudio.com
Please visit our web site. It will have many new pictures
and pages devoted to what we have discussed in this
newsletter.
We have teamed up with a few of our retail dealers.
Watch for our ads in Stereophile and The Absolute Sound.
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