Woofer pumping possibly due to tube amp when playing vinyl
Wrong on all of it. You tried three different clamps. If none of them are designed like I said you could try a hundred more and it won’t prove a thing- other than that a lot of record clamps are of poor design. Which is why I made my own. There are some good ones out there. I described exactly how they should look and work. Get one and use it. Problem solved. |
stereo5 It is not the turntable. I tried my VPI with 3 different clamps and none made any difference. I still use the KAB with my Technics SL1200G and even though the noise was less it wouldn't go away until I used the KAB ...If it's not the turntable, or the match between cartridge and pickup arm, then it's the set-up. Rumble filters are really a Band-Aid. They work, but treat the symptom, not the root cause. |
Well other than a clamp that works wonders, I’m not sure what is left for me to try. Here is a list of things most things I’ve done: different cartsHead shell weightsAdjusted tracking force different count wts different antiskate checked leads different mats different TT’s - in various locations different phono pre different pre Amps checked different inputs on preamp different amps moving TT to concrete floor Different cables lifted motor off table so only belt spun platter not sure what to check next. I would have thought that two different turntables without we skipped two different results but it doesn’t |
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Not sure if this is your issue but In 2010 I have a very significant woofer pumping issue with vinyl That’s when I had a triplanar arm and ZYX Universe cartridge We looked at isolation, the room, Speaker porting, suspension, etc etc like you are doing. Like your situation it was worse on the outside portion of the record and exasperated on records with subtle warps a lot of great insight from those posting here and our local guru here in New Orleans Richard Gray and Thom Mackris of Galibier converged on a solution. Major thanks to both. Finally resolved what was wrong the feather test - moving a feather lightly against the cartridge on the outer side parallel to the record should move the head shell and progress the record forward if the cartridge doesn’t respond to the feather’s light touch and move inward then The tonearm bearing isn’t moving properly The tonearm bearing wasn’t moving suficiently so the cantilever was moving up and down some instead of the cartridge moving in mass. It would follow the groove forward but not have enough sensitivity to track things vertically correctly in harmony with the cartridge. That was what was causing all the pumping It also isn’t kind to your deliccate cantilever suspension. Most likely the bearing was restricted by dust in the equation. I had the arm sent back and the bearing replaced by Triplanar and all was well Since then I move up to a Durand tonearm. I know you mentioned this was occurring with two turntables but each could be suffering from the same bearing issue to different degrees. I wouldn’t rule the tonearm bearing out. Particularly if you hadn’t played them in a while, there were similar dusting habits or if they are located in the same environment. It is certainly worth a test. Tom |
