Quickie mods

Coincidently the white power supply and ground wires came from some old audioquest type 6 wire I experimented with 10 years ago.  It was nowhere near as good as Kimber 4TC as a speaker wire but I liked the solid core wires and saved them for projects just like this.  One of the things I like about this hobby is how reusable things like caps, resistors, and wires can be.  The only down side is hanging on to it all over the years takes up space.

Oh and you don't have to feel too crazy about wires making an audible difference.  Check out what Shunyata has come up with as far as measurable differences.
 
Funny how wire gets used more than once. I keep using AudioQuest 'Midnight' speaker cable for all kinds of hook ups. But I have to remember that the ground wire has a semi-conductive insulation. About 10 ohms .
 
I also noticed that Rob has his Quickie mounted in a cut out block of foam. That is a very good idea! I like it. You dont have to worry about heat or anything. Might help with microphonics.
 
Eric,
I tried foam mounting, with the high density packing type, low density cushioning and a open air type I got from work.  Neither worked for microphonics.  I don't have alot of external vibrations that aren't caused by me mucking around with components.  I settled on copper tape and tube dampers.  In my mind it made a difference (putting the Quickie on it's own shelf may have helped too but that wasn't part of the experiment so it's discounted...) and it looks really nice.  I want to try some thin copper wire to wind the tubes in...
 
I'm glad to see Bottleheads coming up with approaches to deal with microphony. It's simply an inherent part of using directly heated tubes for low level signals. They sound so resolving that we need to keep coming up with approaches to deal with this one potential shortcoming. We seem to have gotten the other issue - hum- sorted out pretty well. And if one can create an environment where the directly heated tubes don't pick up vibration, well, in my book there is nothin' else that sounds as good.

I have seen some reduction of ringing with the application of copper tape on some tube types by looking at the ringing on a scope. It doesn't eliminate it, but it can reduce it noticeably. Our racks are composed of a stack of Ikea Lack tables, which are very low mass. Many years ago a friend, Andy Bartha, made me a big batch of pucks made from lead shot mixed with a pourable silicone sealer made for patching mobile home roofs. He molded them in different sized muffin tins. I had the inspiration to place a set of these high mass pucks under the Bee Pre and a set under my Eros. They seem to reduce the energy transfer of any vibration of the shelf to the chassis quite well. 
 
The foam worked well against ground borne vibrations but couldn't control vibrations transferred through my cables.  My ultimate quickie solves that by providing a very stable chassis.  
 
Good thinking, all of this. Follow the source. If it is cables, change cables. I use Nordost because of that very fact. But I also believe in the greater mass approach. Then, if isolation is added at the right juncture, that is all we can do...now where IS that right juncture? I thought that the base of the tube would be effective, but no, there is still vibration coming directly through the pins. Detaching the tube socket may help us here. I am planning to put my Quickie into a more suitable enclosure. That may be the time to deal the rest of this issue.
 
You might try the trick we use on the SEX amp, putting a soft o-ring between the socket and the chassis. It will require longer screws.
 
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.
 
denti alligator said:
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.
Click to expand...

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.
 
denti alligator said:
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.
Click to expand...

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!
 
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.
 
denti alligator said:
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.
Click to expand...
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
 
Alonzo said:
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
Click to expand...

Hmmm...  If you're hearing the ringing WITH the music then you may want to consider trying some different tubes.
 
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.
 
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?
 
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
 
You must log in or register to reply here.

Similar threads

A
Need head phone help
Replies
3
Views
577
atul.mehta6
A
Thermioniclife
MERRY CHRISTMAS
Replies
3
Views
2K
Paul Birkeland
Paul Birkeland
Doc B
Doc B selling large (classical) portion of LP and tape collection
Replies
2
Views
277
jgarr4714
J
B
Gassy 2a3?
Replies
11
Views
12K
Paul Birkeland
Paul Birkeland
Jameson
  • Sticky
Pipettes, Subettes, and some accessories are retired
Replies
0
Views
135
Jameson
Jameson
Back
Top