Bottlehead Forum

General Category => General Discussion => Topic started by: aragorn723 on January 14, 2025, 02:21:44 PM

Title: tube ringing
Post by: aragorn723 on January 14, 2025, 02:21:44 PM
The 3s4s on my Quickie are ringing while music is playing, so I'm looking for some tube dampers to get rid of that sound (it's almost as loud as the music, but the tubes are measuring pretty high, so newish).  Was looking at Herbie's tube dampers, but have been out of stock on the right size damper for a while.  Any other suggestions?  Interestingly Herbie's claims to improve the sound with their dampers too..

Dave
Title: Re: tube ringing
Post by: Happy Ghost on January 15, 2025, 05:32:28 AM
Any other suggestions?  Interestingly Herbie's claims to improve the sound with their dampers too..

I have had good experience with Herbie's tube dampers especially on my C2A.. It improved the sound and got rid of some persistent background hum..
Title: Re: tube ringing
Post by: aragorn723 on January 17, 2025, 03:34:33 AM
They're back in stock now.  I was a little hesitant to pull the trigger on them, but there are lots of good reviews, so we'll see how it goes..  Would you say the difference in sound is pretty significant?
Title: Re: tube ringing
Post by: Happy Ghost on January 17, 2025, 04:26:00 AM
Would you say the difference in sound is pretty significant?

Yes.. IMO it was a marked improvement..
Title: Re: tube ringing
Post by: Paul Joppa on January 17, 2025, 04:52:03 AM
For what it's worth, there seems to be a LOT of variation  among 3S4s (also called DL92, and a few other designations), in regards to microphonics.
Title: Re: tube ringing
Post by: aragorn723 on January 17, 2025, 05:03:25 AM
I wouldn't doubt it.  I recently got rid of some Westinghouse tubes and got JAN Sylvania's from 1944.  By far some of the most neutral and amazing sounding tubes i've heard in the Quickie.  These have to work, I can't imagine switching to something else!   8)  There's something to be said for American tubes.
Title: Re: tube ringing
Post by: Doc B. on January 17, 2025, 08:45:19 AM
I found that Herbie's dampers tend to damp high frequency ringing more than midrange or low frequency ringing. You might try setting something heavy on the chassis for the lower frequency stuff. Have also had some success in the past with copper tape wrapped around the tube with a wire soldered to the tape that connects to the ground buss. Works as a damper and also a shield for EMI.

Location matters too. If the tubes are near speakers they will ring a lot more than if they are far away from them.
Title: Re: tube ringing
Post by: RPMac on January 18, 2025, 03:40:45 AM
For what it's worth, there seems to be a LOT of variation  among 3S4s (also called DL92, and a few other designations), in regards to microphonics.

I have found this to be true with 3B7s for my Stereomour, but when I find one that doesn’t try to sing along (at 500Hz), this amp trashes everything else.
Title: Re: tube ringing
Post by: aragorn723 on January 30, 2025, 04:11:04 PM
Got them in the mail the other day.  It seems like they press on the tube a lot, but definitely noticed a huge reduction in ringing, and also more details like others have noticed.  Loving it!

Dave