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Component vibration isolation question

I understand the need to eliminate or dampen vibration on such things as speakers, CD players, turntables, and tube gear (especially phono stages). All these component have mechanical moving parts or are delicate (as in tube gear) and any source of unwanted vibration can affect the SQ. However, I don't understand how SS equipment, cables, etc benefit from isolation devices. I would think the various spikes, pucks, racks, etc that are marketed as essential to eliminate the effects of vibration are meaningless on SS equipment. What am I missing?

J.Chip
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Showing 7 responses by bdp24

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bdp24
9,412 posts
 
Yer preachin’ to the choir, @toetapaudio! I use Ingress roller bearings on top of my old Townshend Audio Seismic Sinks, ’cause the bearings aren’t very stable on top of bare springs (I realize you suggest a platform be used between them, but for some of my components that’s not possible). I have Townshend Pods everywhere they’ll fit (they’re about 1.75-2.0" tall when compressed), and Machina Dynamica Springs where they won’t. I haven’t used the Ingress bearings with the Pods, but now that you mention it I guess I should!
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bdp24
9,412 posts
 

@elizabeth, have you tried roller bearings under your shelves? Ingress Engineering in Canada has some great ones at reasonable prices. Recording engineer and Maggie 3.7i owner Barry Diament has them under all his gear (recording and monitoring), including his Maggies!

If I had current Maggies (I have "only" Tympani T-IVa), I would have them on Mye stands fitted with Townshend Audio Seismic Pods (or Machina Dynamica Super Stiff Springs), which are even better than roller bearings at providing close to absolute isolation. Barry likes them too ;-) .

bdp24's avatar
bdp24
9,412 posts
 
The Townshend video to watch is the one he filmed in a room set up with a table, on which are placed two separate motors, onto each of which is attached a thin metal arm with a bungy cord having a weight on it's end hanging from it. In this video, Max explains the theory and physics behind his seismic isolation design, and then demonstrates it's effectiveness. Well worth your time, honest.
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bdp24
9,412 posts
 
I wonder how many readers have yet bothered to watch the Max Townshend videos viewable on You Tube? And if not, why?
bdp24's avatar
bdp24
9,412 posts
 

In his article in Stereophile, Shannon Dickerson (bet the kids in school made his life Hell ;-) makes an extreme statement that is in direct opposition to the ideas propagated by MG. After establishing the premise that any vibration added to the signal is distortion (well duh), and that vibrations therefore need to be kept out of reproduction equipment (MG’s ideas have already been disproven by this point in the article), Shannon declares that "You cannot mechanically over-damp a structure or component that that is not designed to be a transducer."

He then lists the things in a system that CAN be over-damped: electronic circuits (he is speaking of damping in electronic terms, not physical vibrations), loudspeaker Q, phono cartridge/tonearm resonance, etc. But NOT a component chassis or equipment rack---they should be as non-resonant as practically possible. Shannon dismisses the idea of "tuning" as merely shifting resonances around, and attenuating them in a frequency-selective manner. Maple shelves, anyone? ;-)

bdp24's avatar
bdp24
9,412 posts
 
Read Shannon Dickson’s Stereophile article about vibration (link provided by GK on page 1 of this thread), and compare it with all of MG’s thoughts on the subject. If one sounds (pun appropriate) correct to you, the other will sound incorrect. For myself, it’s an easy and obvious choice of which path to take.
bdp24's avatar
bdp24
9,412 posts
 

Thanks for the link to the Shannon Dickson article, Geoff. I don’t remember it, though I must have read it at the time of it’s publication. I was into it only two paragraphs when Shannon revealed his wisdom on the subject of vibration control:

"Knowledge can also help one avoid falling prey to the "Tweak-Of-The-Month" mentality characterized by mistaking tonal manipulation for improved resolution." Maple platform, anyone? ;-) For the price of one 3" thick 19" x 16" maple plank, a 4’ x 8’ sheet of 3/4" thick, 13-ply Baltic Birch can be bought, cut into enough pieces for many platforms, each comprised of two pieces of the BB with constrained layer damping between them (Green Glue, ASC Wall Damp, EAR Isodamp). Far stiffer than solid maple, with a higher resonant frequency, lower in magnitude and better damped. No "tuning" required.

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