Pure Class-A Amp under $2000 (USED)

If you’re fortunate to find a used Clayton Audio S50 while your radar is up I’d say consider yourself hugely lucky and that you jump on it ASAP.  50 and 100Wpc of sweet-sounding and pure Class-A power into 8 and 4Ohms, respectively.  Read the reviews of Clayton amps and I think you’ll find them quite special too.  Best of luck in your search!

https://www.usaudiomart.com/details/649787192-clayton-audio-s50-class-a-amplifier/

I’m not saying I’m 100% correct on this, but in the name of safety a good rule of thumb is to add 50+200=250, divided by 2 = 125watts.

@thehorn You’re likely not correct on this. Understand that you’re conveying general guidelines, but general guidelines are just that and don’t apply in all situations, and this is one of them. For one, the OP is looking for a Class A amp, which out of the box affects how many Watts are required as they mostly double power into 4 Ohms and given their more robust power supplies can provide plenty of headroom even above that. Then, there’s the speaker specs. Using stated specs can be indicative but not always determinative. Case in point, here are JA’s actual measurements of the Venere 2.5 whose stated specs are near identical to the 2.0…
“The Sonus Faber’s voltage sensitivity is specified as 89dB/2.83V/m; my estimate was a little lower than that, at 87.7dB(B)/2.83V/m. The impedance is specified as 6 ohms; the Venere 2.5’s impedance magnitude and electrical phase, plotted against frequency, are shown in fig.1. There is quite a large variation of impedance with frequency, the magnitude remaining below 6 ohms for most of the midrange and bass but staying above 9 ohms for the entire treble region. Though there is a minimum value of 3.45 ohms at 111Hz, the phase angle is extreme only when the magnitude is high. The Venere 2.5 will not be hard to drive.”

Further, I had the 2.5 in my system and will attest they were not hard to drive at all, and my 100Wpc Class A/B amp drove them to very loud levels without even nearly breaking a sweat. And I’d have actually NO reservation saying a 50Wpc Class A amp would be more than sufficient to drive the Venere 2.5, which is why I recommended the Clayton S50 would be a great choice here. I’d even say something like the Pass XA30 @ 30Wpc would be perfectly fine because, as Pass amps are conservatively rated, it’d have more than enough juice to drive the 2.0. Point being, using top-level, basic specs without looking further under the hood can lead to misleading conclusions despite whatever good intentions were involved.