Audio feedback and Turntables

This is why when you record (digitize) from a turntable, it should always be done with headphones!

Even on highend systems, I have seen "ghost images" of the transients when you look at spectral analysis, especially when you have a snare hit and then silence. It's almost like print-through on tape!

Sombunya

Excellent question, excellent point... I always wonder about Turntable right in the field of speaker with substantial bass output ... I have mentioned exactly the same thing in this very forum. I have always suspected that the place for a TT is not where the speakers are ... It seems to me counter-intuitive to just place something that relies on mechanical vibrations to play in the field of strong vibrations producing item .. yet that is what is practiced in mos of the installations including the most carefully laid-out room systems in the US and elsewhere... I know for a fact and always thought it was the best solution to do what some Japanese audiophiles do: Place the TT in a isolated, sound-proof room/cabinet/closet .. The problem is not one of real estate or money IMO, it is of ergonomics and aesthetics .. Changing side would involve a trip to the other room and back in time to listen to the music ... that could even require some running .... Not convenient, not practical. The vibration problem is mitigated by the suspension and vibration reducing material . I used a Vibraplane, had two as a matter of fact which I used for the CD transport (made no difference under the CD transport made a world of a difference under the TT) but I am not too sure how you deal with airborne vibrations that hit the arm, thus the cartridge ... The other problem is of aesthetics ... How do you hide such carefully crafted object as a TT or a tonearm? .. They are the equivalent of Audio Bling .. Speakers can be nice, amps too, even CD tranport can be good looking ... but when it comes to TT , they are the most beautiful objects in all Audio. It would be like Buying a Picasso or a MAtisse and hiding it in a lock never to see the light of the day.

sombunya said:

There is a wall that separates the living room from my bedroom. My system is stacked near this wall. I will be boring a small hole through it and build a shelf on the other side to set my TT on. It's not too far a trip to walk back and forth and the cables can remain short.

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Well unless the wall is isolated with RC or a double leaf, then this would be almost as worse than in the same room. I'd suggest just placing the TT on a good rack on the other side of the wall.

hhmmm...
thought the same thing...LOL

http://thecarversite.com/yetanotherforum/default.aspx?g=posts&t=7849

Still have to deal with airborne vibrations (sound waves).

DonH50 said:

Still have to deal with airborne vibrations (sound waves).

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Well if it's in another room, then that shouldn't be a problem.

I was talking about the suspended arrangement linked in the post above mine, assuming it was in the same room.

As to your comment, yeah, shouldn't be, but you must not have teens in the house...

If you are interested in this subject you should watch this video: Edgar Villchur "AR Turntable"

http://www.youtube.com/watch?v=OOlAua3tBSw

In order to test the susceptibility of your turntable system to sound feedback you should listen using sealed headphones in a separate room while your turntable plays a silent groove from a test disk and your system plays a CD at normal volumes or use any kind of audio recorder for later listening. If you have access to a PC sound analyzer you can even find the critical resonance frequencies of this type of feedback.