Quicksilver audio silver 88 mono amps

Hi @augwest  I have the Quicksilver 60 Watt monoblocks and to deal with some brightness, and on the suggestion of @decooney (here), I went with the Genelex Gold Lyon KT77s. I've been happy with them. At this point, I'm pretty sure that my low ceiling is the main cause of the brightness (I've put nice tubes in other sockets, too, so it's not them), but my sense was the the 77s helped. FWIW, I have a QS Line Stage preamp with good NOS tubes in it, too, and an R2R DAC.

@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.