Quickie mods

[denti alligator]

To what degree do the microphonics decrease the quality of the sound? I don't hear that dramatic of a difference between listening on headphones (where the microsphonics should be reduced) and out loud.

[corndog71]

To what degree do the microphonics decrease the quality of the sound? I don't hear that dramatic of a difference between listening on headphones (where the microsphonics should be reduced) and out loud.

With my original Quickie I only heard them when my fingers are bumping against the cables or tubes.  If I'm not touching it then I don't hear any.  I too wondered if they may be affected by high volumes but I don't listen at high volumes very often and even when I do it still sounds fantastic.

[earwaxxer]

To what degree do the microphonics decrease the quality of the sound? I don't hear that dramatic of a difference between listening on headphones (where the microsphonics should be reduced) and out loud.

I 'thought' I heard an increase in resolution after I properly damped the tubes. This may be totally subjective.

I liken it to how a camera looses resolution when there are extraneous light rays refracting at odd angles on the front element of the lens (flair).

To me it makes sense, due to the ability of the tube to produce sound from amplifying extraneous sounds from the room. Anyway, I sleep a little better!

[4krow]

Try to take photo while riding on a moving train. Ya gotta compensate. Same with the audio I think. There is a point of diminishing returns, I'm sure, and yes, if you don't play music that loud, I agree the room acoustics and air borne waves don't matter much. I am the same way. I listen softer and closer than before.

[Alonzo]

To what degree do the microphonics decrease the quality of the sound? I don't hear that dramatic of a difference between listening on headphones (where the microsphonics should be reduced) and out loud.

Sam,
I have a couple of pair of tubes that you can hear the ring just below the music level when played on ~half  the pot range (thru my speakers).  To me thats a significant decrease in quality.  My current pair is only noisy when distrubed no matter the volume level.  They have rubber grommets seperating the tube bases and copper tape on the tubes.  It is also isolated with sand filled feet until I can build a sandbox that looks good.
Alonzo

[corndog71]

Sam,
I have a couple of pair of tubes that you can hear the ring just below the music level when played on ~half  the pot range (thru my speakers).  To me thats a significant decrease in quality.  My current pair is only noisy when distrubed no matter the volume level.  They have rubber grommets seperating the tube bases and copper tape on the tubes.  It is also isolated with sand filled feet until I can build a sandbox that looks good.
Alonzo

Hmmm...  If you're hearing the ringing WITH the music then you may want to consider trying some different tubes.

[Alonzo]

Oh yeah, those tubes are gone.  Got a good set of Tele's in there now.  Wish you could recycle/reform problem tubes, hate to throw anything away.

[Doc B.]

I was at a swap meet with my dear old bud Crazy Eric, maybe 10 years ago. Eric would move about eight times as fast as anyone else at the swap meets and snag the best deals at the meet, then go back and cruise the possibilities left. So at this particular meet he finds an RCA-UX250 tube. Very collectible, I sold a pair of NOS for $800 in the early 2000s. The structure inside this one is tilted, looks like it could definitely have a problem. He buys it for $15. Walks over to me and says, "here goes nuthin'. Whaps the tube hard in his hand, a couple times. The structure straightens right up. Tube tested fine after that. 

The lesson learned? Smack 'em around if they don't behave. You might knock something that has been ringing into a state that makes the tube settle down. Or not. What have you got to lose?

[Alonzo]

Ha!!! So that's the reason my Dad used to hit the TV....couldn't make it any worse.

[Zimmer64]

Hi there,

Being a new Quickie owner, I am very excited about further improving the already awesome sound of it. So far I have replaced the pot with an Alps RK27 and installed Telefunken's.

Main concern at the moment is microphonic. Today I have put self adhesive foam strips (the stuff one uses to seal window frames) between the base and the top plate, which reduced microphonic considerably.

I plan to also try to make the top plate more rigid and stable. I thought about glueing small wooden bars to the underside of the plate. What are your opinions about that?

I have also ordered new coupling caps (Claritycaps mr), which I am looking forward to.

Best

Michael

[Doc B.]

Making the plate more rigid will simply transfer the vibrational energy into the microphonic tube more efficiently. What you want is soft, squishy mass that impedes the transfer of the energy. One thing that can help is some lossy material between the base and the shelf it sits on. I use these little lead shot and silicone pucks. Something like sorbothane hemispheres will probably work well too.

[4krow]

Just got doing the Sorbothane idea to support the plastic plate from the box, and yes, there is a notable difference.

[Zimmer64]

Thank you Doc B. Sounds plausible. I will change my strategy accordingly.

Michael

[Zimmer64]

Guys,

What kind of copper tape are you recommending and how did you apply it? Would this work: http://solutions.3m.com/wps/portal/3M/en_US/ElectricalOEM/Home/Products/Catalog/~/3M-EMI-Copper-Foil-Shielding-Tape-1181-1-4-in-x-18-yd-6-35-mm-x-16-5-m-36-per-case?N=4294705660+5428620&Nr=AND%28hrcy_id%3AGSRXMKDHQ2gs_7W8LMHK4C8_N2RL3FHWVK_GPD0K8BC31gv%29&loc=en_US&plmlblid=1273692470463&rt=d&sorttype=list?

Thanks

Michael

[4krow]

That tape would be fine, but I would consider wider tape. You can always cut to perfect width with 2" tape.