My experience with htese has been only favorable. I have 4 placed under my turntable and 4 under my CDp. I use them with the flat side up and use the teflon pucks that come with them between the rounded end and the surface beneath.
I have never tried 3 since 4 has yeilded such good results.
I attest that the turntable does not skip at all and with out I cannot walk with a natural gape in the vicinity of the table. I would recommend using all 4 first and then experiment with 3. As far as the surface on the underside of the component I had some 1/2 glass cut at my local glass shop. I had the match the measurments of the component. Then I place the component on the glass then the glass on the AQ feet. This has worked for years, good luck.
I put them in a drawer! Under my old tt they helped a bit, but now that I'm running pure Redbook I found that Neuance iso/absorb shelves VASTLY more coherent, with much tighter bass and "continuousness", if you will.
Thanks Subaruguru! which side goes up the round side or the flat side?
These devices and other dampening devices do a dis-service to the transfer of music to your ears. Dampening does not selectivly kill only unwanted noise. Yes, these devices make a difference but to me they are all negative.
This one in particular just reduces mechanical vibration. How does mechanical vibration contribute to the sound in a positive manner? Anyway which side is up?
I used these devices many years ago. Does not matter which side is up. They effect the sound quality in either direction. Dampening devices are not selective to the frequencies they alter nor the dynamic structure they alter. I would recommend that you direct couple and not dampen. Tom
If you are going to use just 3, then find the heaviest point of your component, and place them there; the lightest point gets the the other. Usually, the heaviest point will be where the transformer is. Also, put a heavy book on top of the cdp; it will further dampen vibrations. BTW, I would stay away from steel/brass cones; they seem to offer better resolution, but highs have been distorted in my experience.
Now you have 2 positions to trap the noise,top and bottom. No exit to escape from..
Theaudiotweak wrote, "Dampening devices are not selective to the frequencies they alter nor the dynamic structure they alter."
This is untrue. All dampening devices affect some frequencies more than others. To expect otherwise would be to expect a material to react identically to differing energy inputs, which is clearly impossible. Sorbothane's website has detailed and specific data on the quite frequency-dependent effects of different sizes, shapes and durometers.
That said, Sorbothane can certainly cause problems as well as solve them. Using the appropriate Sorbothane product beneath the feet of my A/V cabinet yielded significant audible benefits with no downside. That tweak was an easy keeper, as were the four Sorbogel feet beneath my turntable. OTOH, Sorbothane feet beneath my speakers (B&W N803 on a carpeted wood floor) were an instant music-killer. Took those things out of there and put 'em back in the drawer.
Like all tweaks, listen with care and don't be afraid to give them up if they don't work.
Dougdeacon, Sorbothane is a frequency absorber and a damper. Which selected mechanical frequency did you choose to alter that did not change the frequency before or after the fundamental? By changing the Q did you not squelch the dynamic structure? All dampening devices are also storage devices. So how much was absorbed and how are you to predict the time and selective frequency to be released?
Theaudiotweak: sorry if I wasn't clear. I did not mean that Sorbothane doesn't react to/affect all frequencies. Clearly it must, but it reacts to/affects them differently. Sorbothane absorbs higher frequencies more than lower frequencies. As a result, it lowers the overall system resonance frequency. How a Sorbothane-floated system responds to vibration depends on the frequency of that vibration.
Sorbothane lowers a system's resonance frequency by absorbing vibrations above that frequency. The farther above the system resonance frequency an incoming vibration is, the more of it will be absorbed. This absorbed vibration is largely converted to heat, *not* released later as vibration.
OTOH, Sorbothane tends not to absorb vibrational energy below the system resonance frequency. At those frequencies, it seems to act less like a damper and more like a coupling device.
If you want to lower the natural resonance frequency of a system, (ie, to reduce exposure to support-borne vibrations above that frequency) then the appropriate Sorbothane feet should have reasonably predictable results. This is what I wanted to do with my equipment rack, which is sitting on a suspended wood floor that is easily excited by my speakers. Floating the rack on Sorbothane yielded greater clarity, faster attacks and a quieter background at all frequencies above 30 Hz or so. Frequencies below that, as best I can tell, are slightly amplified but seem about as clear as before. This is consistent with the worksheet on Sorbothane's website, which calculated that I'd have a system resonance frequency of about 28 Hz.
If, OTOH, a component is intended to be *producing* multi-frequency vibrations, as a loudspeaker is, we would predict that placing any vibration damper beneath it would impair its performance. That was exactly my experience with Sorbothane beneath our floorstanders. Attacks were severely dulled. Very bad.
Sorry to Bundeel for highjacking his thread with such a lengthy post. Enjoy the music!
My experience with Sorbothane beneath electronics has been the same as Dougdeacon's beneath speakers. Severely dulled, slow and dark. Sucked the life right out of the music. So if this is what damping is all about then direct coupling is the way to go. Remember your electronics were designed to operate over a much wider bandwidth than the music we hear. There are also harmonics of fundamentals that extend way beyond what we supposedly can hear. If we squelch these harmonics either by accident or by design then we are altering the life of the music. Couple not dampen..Tom's point of view..
Interesting points Tom. I've never bothered to try Sorbothane beneath electronics. Guess I won't!
Putting it just beneath the feet of my rack isolates the components without directly dampening them. A quieter rack must be good. No component is designed to work while being shaken but, as you say, no component is designed to have its own vibrational energy damped either. This has been very helpful, thanks.
We can now explain why, for example, the reportedly excellent Grand Prix Audio racks sound so good (multiple isolation/dampening layers) and also why GPA advises us *not* to isolate or dampen individual components. Let the rack do the isolation, leave the components free to work as designed.
There I go again Bundee1. Sorbothane pucks beneath my TT did isolate it from footfalls. Can't say whether they affected the sound because I've made too many other system changes recently to tell. I'll have to A/B, like you. The discussion above implies I should take them out and let the squidgy bits beneath the rack do the protecting.
Please guys feel totally free to contribute to this thread. You guys are still on topic and Im benefiting greatly from your experiences. Keep this discussion alive, and thanks for sharing.
I may be the old guy here. I have, and am guilty of the following . Making several changes to my system at the same time. My enthusiasm and excitement sometimes clouds my better judgement. I have to temper my emotions and not rush to a premature conclusion. Only one device or one measurement at only one single time, that is the only way to truly measure a change and hopefully an improvement. I will try to remember this. Tom
Enthusiasm? Excitement?? Just for music??? Shame on you! Nobody else here would stoop to that level.
The first piece I happened to listen to on our new speakers was Beethoven's 6th. Couldn't get through the 5th movement without tears. Didn't even try to :)
I just brought 4 "Vibrapods" Model #: 2 for my "Oldie" Technics SL-120 Rega RB-300 arm & Ortofon Jubilee MC cartridge.
Any opinion on those items...Please?
Vibrapods beneath my CDP sucked the life out of the music. Sorbogel footers beneath my Harmon Kardon/Rabco ST-8/ADC XLMII did the same. I'm 100% behind TheAudioTweak on this one: keep these things away from any component whose parts are designed to move or vibrate. (He would say that means *all* components, and I wouldn't necessarily disagree.)
The only benefit beneath my TT was protection from heavy-footed pedestrians. The cost was a serious degradation of HF transients and clarity, sort of like having VTA set too low. The solution is obvious, ban heavy-footed pedestrians AND dampening devices from the vicinity of your TT.
P.S. It's possible a suspended TT like a Linn *might* react differently, since the platter/arm/cartridge would be more isolated from a deadened plinth. If your Technics is a direct drive, this (untested by me) theory wouldn't apply. My guess is you'll do better without them. Why not try and let us know?