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September 29, 2020, 07:43:10 AM

Author Topic: Another damping mod for quickie  (Read 279 times)

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Offline aholata

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Another damping mod for quickie
« on: October 29, 2019, 07:29:55 AM »
Started some damping mods for my quickie and thought i'd try the copper tube mod as it's been reported to be success. Well while sourcing copper tube at work (a biggish paper mill) thought came to me to use brass tube or similar stuff, since i've read positive stuff about brasses vibration controlling abilities from one manufacturers page, whom i later learned actually does this stuff for tubes too, search the forum it has come up here too. But to the point, i went with cheap solution which worked really well, actually tested against copper tubes and it was no comparison, brass was way better. What i used was some brass hose barb lined with velcro for snug fit.  I cut the bolt of from the end but it could be beneficial to keep it for extra mass, will try that next.

-Tatu-

Offline Bonzo

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Re: Another damping mod for quickie
« Reply #1 on: October 29, 2019, 08:52:21 AM »
Well done!
And a lot of nostalgia for the good old Quickie  :'(  :)
Bisogna avere orecchio!

Offline IndyNate

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Re: Another damping mod for quickie
« Reply #2 on: February 19, 2020, 06:27:12 AM »
Nice engineering! FWIW, I too had pretty bad microphonics with my Quickie, so rewired it. I put a 500k pot after the circuit, replacing the 100K stock pot. Not entirely sure why it works so well, but, letting the 3S4 swing the full input voltage, then attenuating eliminated any ringing. You can still hear it if you knock them, but, very very quiet otherwise.

Offline Paul Birkeland

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Re: Another damping mod for quickie
« Reply #3 on: February 19, 2020, 03:57:58 PM »
I put a 500k pot after the circuit, replacing the 100K stock pot.
That will make the output impedance of the Quickie vary significantly, and you'll likely notice very, very rolled off treble in certain level positions.  You could try a 25K pot instead in this spot with very short cables to decrease the dependence of performance on the position of the volume pot.
Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man