First foray into Class A amp -- recommendations

Mtrot, I wouldn't get too hung up on Class A biasing to be honest, it is mostly marketing bs. For your budget, I would look around for a 2nd hand Modwright KWA-150SE. I saw one on the 'Gon last year in excellent condition asking $3300. The Modwright is warm and tube-like, has PLENTY of power and has amazing inner details. My two cents.

09-15-14: Zd542
"09-12-14: Melbguy1
Mtrot, I wouldn't get too hung up on Class A biasing to be honest, it is mostly marketing bs."

Class A actually means something. Its an actual feature of the product. I wouldn't call it BS. Getting hung up in marketing, BS or not, is a choice. Sometimes learning about audio and selecting the right products is hard. And that's just the way it goes. But if you take the time to figure out what is right for you, and purchase accordingly, you'll be far happier in the end. If you don't, it never ends. lol.

You're right, what would I know...

@Zd, fair enough. I certainly wasn't criticizing Class A power as my Vitus runs in pure class A up to 25 watts true rms and can be manually switched to class A/B mode which delivers 100 watts true rms and is great for home theater duties. In Kl.A mode the Vitus can change to Kl.A/B mode at very high volume levels or under extreme load, but does so instantly without switching. That is what I meant by pure Kl.A. The Krell fanbois endlessly claim that their amps are pure Kl.A, when in fact they use a sliding bias scheme as confirmed by John Atkinson. Only a few pure class A amps have been built, including the Threshold T800 but they were prone to failure.

What I meant is, most customers want the marketing bs and claim they do not. Amps like Boulder and Rowland market Class A amps which in reality are highly biased class A/B amps. Vitus do not change the bias based on input signal amplitude – that has nothing to do with real kl. A. It's just a marketing gimmick. What Vitus's research has shown is that when the transistors they use has a core temperature of about 70degrees C then the music becomes REAL Liquid – listenable for hours – not the usual competitor “bleeding” ears after 30min. Some call it dynamics, “air” in the high freq – I call it a headache.

Moreover a lot of manufacturers routinely quote peak power figures, or don't quote "true RMS" power just to impress people. Vitus quote their power figures in "true RMS" which is a correct, but less impressive spec. Also, Vitus is using in-house designed UI-core transformers which are much more efficient than typical toroids used by most manufacturers and loses max 1.5v tested. That is another reason why specs on paper mean very little.