Quicksilver v4 monos vs CODA Continuum No. 8 Version 1.

I owned 2 of these Duo XD amps before and liked them more than the #8.

I’m pretty sure that Krell Duo 300XD is good sounding amp, but unfortunately I have some bias for vent cooling concept. Probably sounds paranoid, but the idea of some moving parts inside the amp kind a disturbing to me. 

What are the speakers you will be using?

Class A amps don't transition to any other class. They run at full power all the time.

Class A/B run in class A until the signal is high enough to transition to class B.

The class A to A/B transition feature is mostly just marketing.

I think Pass Labs Class A amps transition to A/B as a protection against clipping.

I have not heard the QuickSilver monos but at one time owned the CODA #8 and now own the CODA #16. For the price of the #8 I would get this instead.

Krell Duo 300 XD Like new Dealer Ad - US Audio Mart

I owned 2 of these Duo XD amps before and liked them more than the #8. They are smoother sounding than the #8. The amp that I linked above is 300 watts of iBias Class A. It sounds amazing. What that means is that the amp is not super-hot nor wasting a lot of electricity. It is not heavy either.

I prefer topics like this were never started.

There are about one hundred variables before and after the amp & speaker interface. Every system and listener is unique.

I  was talking about one aspect of the topic in this case which is “opinion” :)

Here's one from a highly unusual perspective:

For me it is the CJ.

It's because given a certain wattage rating the tubes have a much wider high quality working range for my hearing.

(Provided we are matching them with matching speakers, but 1., that was not part of OP, and 2., CJs have no problem driving a vast array of commercial speakers). Pushing class A solid state amps beyond 1% of their peak rated power, and to me they have ALL run out of their high fidelity working range. (While non-class A in general have no high fidelifty working range for my hearing - sure, they sound processed and carefully sculpted, but too unnatural and with unacceptable midrange and highs in general for my perception.)

So, while in this SS case the 320W peak rating is totally irrelevant for me, and this amp would function as a 18W class A when looking at high quality experience. In addition, it's really 1% of that class A that is usable for my demands, aka about 0.2W. The same linear region of the CJ is about 20W that feels high quality to my ears, so we get x100 wider working range from the CJ (x100 more available power for high quality listening). 

Although I use ultra efficient speakers, and 0.2W is about my usual peak demand for loud passages, so even that 18W class A with a usable 0.2W is quite all right for most of my needs.

Indeed, most people do not say what I say about the highs of solids. However, my hearing is quite intact, and I do hear up to 20kHz (despite being 45y old), and any issues above 17kHz are painfully affecting my experience, and I shut such experiences down immediately as i want to keep my hearing intact for the future as well! (BTW that's the secret to avoid losing your hearing: DO NOT LISTEN TO GEAR THAT DESTROY IT!!!!!) -- sorry about shouting, but I'd rather you hear it than lose your hearing....just in case if it's a prority for you, otherwise just ignore and press pg down.... I don't want to offend anyone who thinks otherwise. Just follow your dreams, and enjoy what gives you pleasure, fulfillment, balance and healing.

For those who already lost it and wish you had way better hearing: well, when you have extraordinary hearing it just makes 99% of the even highly regarded gear simply unlistenable!!! So, it's more of a real bad curse than a blessing....

Enjoy the ride, both directions (ss/ tubes) can bring you beauty and fulfillment, provided they are set up with the right synergy and match your needs and hearing.

Let’s stay under the topic. It’s not about my preference. I was asking about yours, if you have any. 

I prefer topics like this were never started.

There are about one hundred variables before and after the amp & speaker interface. Every system and listener is unique.

If that’s the case why are you asking about Quicksilver tube amps? And for that matter Coda class A amps

Version 1 of CODA Continuum No. 8 is not class A amp. It shouldn’t run hot.
Does QS v4 runs hot ?  Probably, in general for living room tubs will be less appropriate. 

If that’s the case why are you asking about Quicksilver tube amps? And for that matter Coda class A amps! You should be looking at cooler running class A/B amps!!

BTW, A true class A amp does not switch to class A/B! If you want a true class A amp you should be a lookin’ at First Watt or Pass amps!

Yes, I’m aware of this fact, but I’m afraid that pure Class A is not the case for this particular situation, cause this choice of amps would be for our family living room and I don’t want to think that my wife or kids could leave it to overheat while I’m not at home. It’s already happened once at my listening room, when my daughter with her boyfriend left my tubs on for a couple of weeks while I was at vacation :)

Preference would depend on exactly what/type of "perfectly" matching speakers I’m using, room space & size to locate one or two amps, how often/long I play music for, and leaving amps powered on for how long? Also the type of music I listen to most of the time. Pick one and always wonder about the other anyhow.

The #8 will be faster and more dynamic, and the V4s can be a little smoother and more relaxed with the right tubes. So, what I would "prefer" is owning both for different reasons and use cases. Similar situation here with different 100w QS tube amps, and setting up for a 50w Class A solid state amp on rotation. After decades of messing around, you’ll find some folks here buy both and resale the one that does not fit their taste and situation as much as they had hoped. Some of this directly relates to their speakers being used. Some amp/speaker combos match better than others and why you see members here trying both, eventually. Best of luck on your preference. 

I am “biased” towards the #8 because I have one. Amazing sound. Maintenance and heat-wise it is also the winner. However it would come down to your preference and synergy with the speakers. 

BTW, A true class A amp does not switch to class A/B! If you want a true class A amp you should be a lookin’ at First Watt or Pass amps!

The Quicksilver tube amps would be my choice! I own Quicksilver gear so I am biased!

Why would you ask a stranger such a specific question if it wasn't related to what you wanted for yourself?

You need to listen to both to decide which you prefer. That's all that matters. Either should be able to power most speakers.

Let’s stay under the topic. It’s not about my preference. I was asking about yours, if you have any. 

You need to listen to both to decide which you prefer. That's all that matters. Either should be able to power most speakers.