Opinions on Power Regenerators and Tube Amps

I think the Synergistic ICs may be the problem. Are you using the active shielding? Is the active shielding connection at the preamp end or the TT end? (might try reversing it). If that doesnt help, try a pair of regular ICs just for comparison (with the arrows pointed toward the preamp)

I don't think you need to worry about grounding the VPI chassis, which is why the don't mention it.
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It is not normal for a tube system to buzz. Some hiss is normal and maybe a bit of hum but buzzing is not.

Glad to see you have isolated the problem to the phono. Now the hunt is on. Try moving cables around to see if the buzz changes, try it without the turntable plugged into the phono stage to see if it is coming from the phono satge or the table, try grounding the turntable to the phono stage, try it without, try grounding the turntable to the preamp, try different interconnects, try moving the phono stage and turntable, try turning off other things in your house like dimmers and appliances.

You get the idea. There is no universal solution so you just have to keep trying things until you get rid of it.

When I first hooked up my latest phono stage the hum was as loud as the music. After trying umpteen different combinations of things you now have to stick your head in the horn to hear anything.

I am using a power regenerator for the high voltage supplies in my integrated and for my phono stage. It does make it a bit quieter but the main reason I use it is my integrated bias is sensitive to changes in line voltage. For your system it may not make any difference.

Yup, can of worms. It definately has something to do with the active shielded cables, which are new to my system, btw. Turning off the switch to all the shielded cables makes a big difference. I have a non-active Looking Glass from TT to phono stage, and an active from phono stage to preamp. I switched those and it made it worse. I need to experiment some more. Herman, thanks for the input......what I have is a small buzz/hum at a very high listening level, with no music playing. it's annoying, but I can not hear it from my chair.

Here's the thing. Can't use active cables anywhere in the phono area. I don't know if that is normal, but with that active cable from phono stage to preamp replaced, and the shielding on for everything else, the hum is very small....and I would never listen at that high volume level. I'm a little confused about active shielding now and in saying that I have probably highjacked my own thread for the third time. Thanks for the ideas though.....I was not even thinking about the cables, obviously......I was thinking about power regenerators.

I love regeneration for sources and as I said wouldn't do it w/power amps. I reread your post. Do you get the hum through the spk w/ only the power amp on or when the pre is on and is set to phono? Thats a minimum of four gain stages if the latter and you will hear a little hum. Especially due to all gain needed for a phono cart. Back to your 120HZ question - it is wonderful and I have not met a piece of gear that can't handle it......unless you have an older TT w/ an AC motor that gets it speed calibration fron the AC frequency. As to N's comment on the lowish power output P-300(300 watts max, I never use but 60-70%of it as I said) it was made to drive sources not big amps. They had a 600watt and 1200watt for larger draw gear. Often a pre,phono,CDP and tuner wont draw but 100 to 200 watts total. In fact the process of turning the AC into DC, cleaning it and then turning it back into AC is what makes it so good. Then setting it to pulse 120 times/sec instead of 60.....well judge for yourself. Don't take our word for it, find a dealer that loans gear for home demo before you buy.

ET