Vibrations in the audio range, whether airborne (sound) or structure-borne
(sound conducted through equipment stands, etc.) are something that vacuum
tube electronics are particularly susceptible to. These vibrations combine with and modulate the audio
in your electronic components, and are responsible for blurring of details,
smearing of the soundstage, and a reduction of fullness, presence and
weight to the sound.
All electronics, and tube gear in particular,
are affected by the sounds in your listening room. The large coupling
capacitors and the tubes are microphonic to a surprising degree. Even
normal electrolytic capacitors used on solid-state amplifiers, and the
circuit board itself are microphonic. Because everything is mounted to
a stiff, resonant circuit board that is nothing more than a sounding board,
they resonate to every whisper of sound in the room, every vibration carried
into the chassis.
For twenty years I've wanted to do
something about this, but never could figure out how to damp the circuit
board to eliminate resonances. In the SA-5000 I devised an elaborate
suspension system that decouples the circuit board from structure-borne
vibrations. Yet the circuit board itself remained undamped and
still responds to airborne vibrations (sound).
What is needed is some kind of damping
material that can be applied to the bottom of the circuit board, yet is
easily removed if access to the bottom of the board is required for
servicing. What would do the trick?
The solution eluded me until now: a
solution so simple and elegant that I feel a little foolish for not
having seeing it: Felt. A thick pad of wool felt between the circuit
board and the chassis completely damps out all resonances. Completely.
The improvement to the sound is
stunningly audible and includes:
- Increased lateral and depth space between instruments and
- More detail: sounds which had been smeared over are now
clearly audible -- you'll hear things you never heard before,
- Deeper, fuller tone, with more presence, pace and impact,
- Instrumental and vocal lines are much easier to follow --
if you're a harmony buff, or like to follow what the piano or
bass player is playing, you'll find every note much more
- Reduction of fatiguing edginess,
- More musical, "believeable" sound.
By eliminating the vibration-susceptiblity of the circuit
board, the sound of your Counterpoint product is transformed. It sounds like it was built with
technique is not something I can do to every model, due to construction
details. And some products are harder to do than others, or require more
or thicker damping pads, so prices vary accordingly. See below for
1. (Setup Fee may be required
if resonance control is done without other upgrades to product. Varies
with difficulty of disassembly/assembly of model.)
Wool felt is dimensionally-stable, fireproof and unaffected by the voltages
present in tube products.
3. By the way -- there is no rocket science here. The fee we charge to
install this great modification is for the labor and knowhow -- the
materials are not expensive. Anyone can do it as a DIY project if they
have the skills. You'll need to disassemble your amp or preamp,
determine how the circuit board is mounted, remove it, determine how
thick the felt needs to be, and order some F-13 gray felt from
www.mcmaster.com, cut it to size, pierce it to clear the circuit board
mounting standoffs, set it in place and reassemble the amp or preamp.
The fee we charge is for the labor and knowhow, obviously the materials
are not expensive.