Quicksilver audio silver 88 mono amps

@augwest
The QS mono tube amps paired with your recapped Thor tube preamp should be fun. Appears VCap was a common upgrade in your preamp, photo here, and nice wide and thick copper strips on the main board, cool.  :) https://www.audioasylumtrader.com/images/y2013/12/100421/FullBoard.jpg

IF it’s a new set of QS monos, give them and internal caps time to burn in with stock tubes or the PSVANE if you get them soon enough. The PSVane BT Mark Its should sound pretty smooth, just helped a friend put them in an integrated amp. After the input tubes burn in on the QS amps, (if new stock tubes) you may want to update those and store the stock ones away. Also, kinda depends on your preamp and tubes too and how bright or smooth they are. It’s a basic balancing act on both ends. Is that brand new or used (burned-in) monos and what input/signal and output tubes are in them now?

@decooney - Yeah, that heavily modified Thor TA-1000 is a special preamp, with a sound I would describe as detailed and authoritative, and neither bright nor dark. Its separate power supply probably weighs more than most components I’ve owned, but I could care less about the form factor.

These are NEW QS 60s received from the factory TODAY with all stock tubes, all brand new. Psvanes have yet to arrive.

One odd thing is that while both the website and owner’s manual reference an LED for setting the bias, there most assuredly is no such thing on my amps! Instead there are ports for voltmeter probes (regular ones, not the 1/4" jacks on the old QS amps).

Since the manual provides no actual numbers, I don’t know what bias current to target. They both ramped up to 70 mA after I installed the factory tubes so I figure that must be close - I’ll call the factory tomorrow. Does anyone here know the actual factory recommendation for THIS current-gen. Quicksilver "60 Watt" mono amp (there have been various QS KT88 amps over the years)? I don’t care about the LED indicator; as an Electrical Engineer and irrepressible tinkerer I would rather use a meter anyway.

@augwest  That is so strange there are no LEDs. I got this unit, new, last April and it has them. How weird. 

So, anybody has compared MC75 with QS 88?
One of my friends had MC75 and it was pretty good, but I was not overwhelmed. Another friend has one of old QS amps and it really sound good. 
My last tube power amp was BAT VK60, replaced by Plinius SA102. I prefer Plinius, but now I miss tube amps. My pre is Audible Illusions M3B. I wonder whether QS 88 will match well with AI.

This is in regard to the Quicksilver 60 monos I got new on 11/11/2020: I was getting a *little* brightness or glare which I attributed to the Esotar tweeters in my Merlin VSM speakers.  They are still the best amps I've found for the Merlins I've had since 2007 and I've tried a BUNCH of them, solid state and mostly tube.

I've been upgrading fuses in my other components and eventually decided to take a look inside the Quicksilvers.  Much to my surprise I found Synergistic Research Red!  I immediately ordered a pair of Purple to try - that's what I just stuck in the Thor TA-1000 preamp and ordered for my PS Audio DirectStream DAC.

In the interim I found a pair of HiFi Tuning Gold fuses I bought cheap on closeout a couple of years ago.  Stuck those in the QS 60 mono's and WOW!  So much more body in the mid-bass and mids, FAR better bass extension and the rest of the music is still there.  I have to believe that the Reds were a step up from a $1 glass fuse but the HiFi Tuning absolutely blows the Synergistic Research "Quantum" Red fuse away.  I'll keep them as spares.

Now I'm KEENLY interested to see how SR Purple fuses compare to the obsolete HiFi Tuning gold in my beloved QS monos.