Class A amplifiers

mrmeaner13 posts06-13-2021 2:47amI have a glorious Class A Sugden A21SE and it never misses a beat, I contacted Sugden and asked them about having it serviced and he said it’s likely not to need looking at.
In my opinion class A can’t be bettered.

It is a fantastic amp! Mine is driving Tannoy Eatons with no issues. There are original a21’s still going strong 30 years later....Sugden, the very first commercially available solid state pure class A, since 1967. Some very ill informed people post here....notice the gigantic heat sinks that adorn both sides of the A21se...the amp is a brute! It is liquid, textured, detailed, holographic, and powerful...at only 30 watts/40 into 4 ohms....50% larger power supply than the previous A21 model, non se version. Built in the UK by one of only 12 employees...even comes with a tag indicating all who had their hands on it...worth every penny of the $3250 paid. When combined with Tannoy legacy, prestige, or gold series speakers, it is pure sonic bliss...end game combo. Add your own tubed phono preamp and it gets even better...Tavish Design makes some great phono preamps.

coltrane1 I have a Plinius SA100 MkIII that checks all the boxes for me. Balanced or single ended inptuts, selectable Class A or AB operation, beefy heat sinks and top notch electronics. Hasn’t had an issue in the past 20 years of operation! Keeps me warm during the long Maine winters too! 🥶

emrofsemanon:
I’ve recently come a long way on my push-pull, class A, SS, tube, hybrid, SET, SIT amplifier journey.  IMHO, my SET implementation (dual Coincident 845 Turbo’s -28 watt and 94db efficient speakers) brought me closer to acoustic music than any other implementation (of approximately 25 different amp combinations- Bedini, BEL, Threshold, Muse, ARC, Moscode, Counterpoint, etc.). Terms like organic and realistic applied.  The realism of an acoustic guitar was breathtaking. However, the tradeoff was weaker dynamics- somewhat thin sounding on large dynamic swings of rock and orchestral music.  In the end, I settled on an Firstwatt SIT-3.  Nearly as good as the Coincident SET in realism, but with a far superior coherent presentation of the entire audio spectrum. I can say I’m temporarily satisfied.

The OP is asking about Levinson gear.  At least the classic era Levinsons, some of them do cook themselves to death. I have a No.23 and the repair job is going to be near $3000.  The authorized repair center explained that the Levinsons do tend to do that. 

While they are "high bias" Class-A Plinius 102 amps cannot be biased "Pure Class-A to their rated 8ohm wattage output". They run A/B.
To have those heatsinks at a constant safe 55-to 60c they would have to be approximately 4 x that size for the amp to be safe to be pure class-A all the way.
Search all you like and won’t find it stated anywhere they are Biased up Pure Class-A all the way into 8ohms, not even on their archived website.
https://web.archive.org/web/20060115165723/http://www.pliniusaudio.com/pro/pro02.htm

At a guess I would say 50watts of Class-A and the rest is B up to 125w

Cheers George