Opinions on Power Regenerators and Tube Amps

Interesting system. I'd agree with Aball, except the kind of buzz he's talking about usually remains pretty much constant regardless of volume setting -- especially since you have a ss preamp. (A nice combo with the Mesa BTW) So you may have some very low level tube buzz, but there may be more coming frome something else. I'd need to know more about how your system is hooked up. (It's unlikely, but maybe the exploded crossover networks dribbling across your floor are picking up some RFI, ha, ha!)

1.) You shouldn't need a regenerator if you have ded. circuits AND your utility company supplies reasonably uniform power, both cycle and voltage. Uniform voltage is especially important for tube amps, unless they have auto-biasing.

2.) Always UNPLUG the system when thunderstorms approach. Just tripping the breakers doesn't always work, and NO regenerator or (ugh!) conditioner, can protect you.

3.) Since you are running digital gear, it could be putting digital "hash" back into the power line and into your preamp -- even when it's turned 'off') Try unplugging the 850 and see if it helps. And in any case, make sure you are uning a quality PC with a floating shield on your 850, AND

3a.) You might want to consider a balanced power unit like the ExactPower SP-15A or one of the BPT units for your front end stuff (and they have digitally filtered outlets built-in for the 850) That would be the finishing touch IMO -- but I don't really think you need a regenerator when you already have ded. circuits.
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So I'll bet the mice are laughing at you too!

If you MUST use a regenerator, get an ExactPower. They don't work the way the (lowish output) P-300 and others do (which is to throw away the whole AC signal and re-build it). Consequently, the ExactPower can offer 1650 watts from 120V wall current, more than enough to power your entire system. But I still don't think you need one.

Conditioners (any kind/brand) are old technology and bad for sonics. STAY AWAY!

After looking at your system again, I would recommend you plug the amp directly into the the 20A circuit all by itself, and get a used ExactPower SP-15A balanced power unit (plugged into the 15A circuit) for everything else.
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I don't know enough about the VPI chassis to really advise you. Typically, the tonearm leads have five connections: two signal leads (from cartridge left and right) which each consist of a hot and ground conductor, covered by a braided shield connected (along with the ground conductor) to the "ring" of the RCA connector at the phono preamp end. In addition, there is usually a black ground wire bundled with the two RCA signal leads that you connect to the ground lug on the phono preamp. This wire goes into the tonearm and is usually connected to the armwand (if it's metal) in order to shield the internal signal wires inside the tonearm.

If the TT chassis is electrically connected to the tonearm, that should be enough, but if it's separate, then you should run another wire from the TT chassis to the phono preamp ground lug.

What kind of tonearm, cartridge, and tonearm cables are you using, and how do the tonearm cables connect to the tonearm?
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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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Look, Racer, I'll go out on a limb and repeat myself:

1.) Forget a regenerator. You don't need one with good ded circuits and good utility service. Plug your amp into the (20A) wall.

2.) Forget power conditioners. Old technology. If you don't believe me, read PS Audio's blurb on their PS-300 webpage.

3.) If you want to do something more for your sources, get a balanced power unit from either Equi=tech, ExactPower, or Balanced Power Technologies. Do your homework and decide which one you like best. I won't make a recommendation, except to say you won't need a megawatt sized one for just the front end stuff (since your amp won't benefit from balanced power as much as just a good ded circuit.)

4.) Do get some tonearm cables made for that purpose. In order of performance (IMO and ones I'm familiar with of course) Siltech, Purist Venustas, Silver Breeze, Hovland Music Groove, Cardas Golden Reference.

5.) Get the same make/model ICs from phono preamp to preamp as the TA cables. Synergy is a good thing in this application (I didn't realize your ML 38 didn't have built-in phono.)
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