Tube microphonics


Hello. I am using Audio Research Ref 750 mono blocks and they in front of my speakers but off to the sides. Someone told me on another site that if I move the amps beside the speakers and not in front of them , my system will improve immensely. It will reduce tube microphonics. What are your opinions of this and I just want to say that I’m very new to tube amps so this is something I never heard of before. Thank you all. 

128x128Ag insider logo xs@2xtattooedtrackman

@tattooedtrackman 

I know this is kind of backwoods, but then again I live in Vermont.

If I had your beautiful setup, here is what I would do before moving your heavy amps around.  @jjss49 if you think this is a bad idea please chime in.

With your preamp, amp and CD player on, I would set the preamp to CD mode.  I would turn my preamp up to about 1/10th volume (any VERY low setting).  I would GENTLY tap on the top of the preamp cover, then CD player cover, and then sides of the amps.  If I did not hear the dreaded (thump) or a tube rush sound I would repeat this, increasing the preamp volume, in small increments until I was at about one half volume.  This should take in total about 25 seconds.

If you do not hear a "thump" through your speakers when taping on your units I would say you have nothing to worry about regarding microphonics.

In my layman's way of explaining it, microphonics are the result of anything vibrating a tube sensitive to microphonics, whether by picking up speaker vibrations, taping the top of the unit having the microphonic tube or any other movement.

 

"Someone told me on another site that if I move the amps beside the speakers and not in front of them , my system will improve immensely."

Oh brother... to much audio internet info.

Not saying a tube can become microphonic, but that looks like perfect example of A.N.

I’d stay away from audio forums and just enjoy your excellent gear.

Edit-It's a free exercise to move them, so try it. Everything in audiophoolery is YMMV.

 

Edit-It's a free exercise to move them, so try it.

Agree 100% in general, and while OP carried them up a flight of stairs, they do weigh 170 lbs each.  And I am pretty sure the more delicate tubes weren't in them as they are now. 

 

Those Ref 750s have 16 KT 88s sitting on top of the amps with only air around them, right? You did not say what speakers you have.  If you have speakers that have large woofers pointed at your tubes, I think they could affect the sound. 

I suggest you move the amps around the speakers, to the sides, behind the speakers, etc. until you find where your system sounds the best, and that may be with the amps in front of the speakers.😁  Use some furniture sliders to move the amps around.  We don't want to hear about you ending up in the hospital.☹

i haven’t bought new audio research tube amp in a few years but i have over a half dozen of them, and in every case, the company puts thick rubber tube dampers on every low level tube when the amp is shipped from the factory, and when replacement tubes are shipped there are instructions to move the old dampers over to the new tubes to be installed

this shows that as designers/makers of the gear, they are definitely concerned about unwanted microphonics affecting the sound produced, and are making an effort to damp them out

so i think it is worthwhile for the op to make an effort to move the amps, as hard as that might be, away from the speakers, to see if a positive sonic difference results