Quicksilver audio silver 88 mono amps

I replaced my high-end Cary tube amps with QS Mono 120s with KT150 tubes. I like 88s too in some ways, shared DNA which led to Mono 120 design of course. At first, I thought these Mono 120s were a slight downgrade for me, even using my better Cary SLP-98 preamp with really good 6SN7 tubes. Had to try it. Keep reading. Had an upgrade vision too for later on. It has paid off. With some good burn-in time and patience, it has paid off big time in stock form, but just like any amp, there is more room for growth with slight tweaks that can turn these amps in to giant killers!

After 100hrs burn in, ditched the entry level stock EI and JJ small signal/driver tubes and rotated in various vintage NOS tubes and tried PSVANE too with much improved results - way better. Several here on Agon messaged me since and have done the same, like a good underground group does. :) Same applies to Silver 88s, Mono 60s. Caution bringing up caps with Mike. It’s not his business plan I gather now days. He shoots for reliability and consistency #1, "no changes" i get it. Some upgrades can help - sometimes.   Proceed at your own risk.

After tube rotation of small tubes, the stock coupling caps are not bad, Mike likes them a lot. I was "okay" with the stock caps. Against conservative judgement (don’t tell Mike - haha, he’ll get pissed off), I upgraded my coupling caps in the Mono 120s to a really high end set of Mundorf EVO Supreme Silver Golds, same as used in $22k Cary amps. Just HAD to know. Bugged me. And, wow, sure enough - it brings the QS amps to a whole new level of 3 dimensional sound, tone, texture. The QS amps have the bones for sure. Enjoy.

For those of you with QS amps, what preamp are you running with them?

Just received the amps today hooked them up, biased the power tubes to the recommended 40a.  It came with kt88 and kt90 tubes, installed the kt90's.   What tubes are you running in your amps, is there anything else to know? 

The electrolytics that are problematic are not the coupling caps. They are both 600v 50 uf rated. I would speak first with Mike Sanders if or when there is an issue. The + leads on both fried manifesting in a howling sound from the amp. I performed the replacement of these caps until my friend who has regular contact with Mike Sanders performed the final fix which involved some minor mods to acommodate a beefier power supply and better caps. 

I went through 5 different pre-amps before settling on a Bill Thalmann upgraded CJ PV9a which complements the QS amps in my set-up very nicely. I am using the Tung Sol KT 150 tubes which I prefer over the KT 88s, ymmv. A matter of trying both. I am unfamiliar with the KT 90 and KT 120 tubes in these amps.

Fsonicsmith you are spot on in recognizing the importance of the power and output transformer in tube amp designs. I am  certain this is the primary reason why all QS amps are all so consistently excellent across the board. The mid monos are a great value at the price as is the 20 watt integrated. I have had zero problems other than the cap issue noted over the past 5 years. Yeah, Mike doesn't seem too keen or that it is necessary to "upgrade" but it must be noted, these products are still built to a price point and better performance can be gotten using better components. I'm with you on that deconney.

Enjoy your Zardozmike, you made a great choice!   

 

@zardomike
IMO, good KT88s paired with nice small signal/driver tubes for those amps. Not a big fan of the KT90s or KT120 tubes in a few different QS amps, could just be me. Others may hear differently.