2. amps-preamps
  3. 1220199838

Buzz about pure class A solid state amplifiers ?

Fellow Audiogoners:

I would greatly appreciate all your input/insight.

Lately both in and out of Audiogon, I have been aware of a "buzz" and numerous praises about the benefits of pure class A solid state amplifiers, as an alternative to the more common high bias AB designs, and an alternative to the transparency and coherence of tube designs.

I have recently auditioned a current production 60 watt Accuphase class A solid state design, a fine amplifier indeed. However, up against my similarly priced VAC Phi 300 class AB stereo tube amplifier (used in ultralinear), it sounded mildly anemic, less transparent, and less coherent/detailed. This is with due respect to Accuphase products, which I have owned and enjoyed greatly.

So....please help me to understand all the purported benefits of the lack of crossover notch distortion, etc with class A push pull soid state designs, when excellent AB tube amps, with crossover notches, are IMHO more cohesive, transparent and resolving in comparison. Have designers, both tube and solid state, basically succeeded in rejoining positive and negative waveforms seemlessly, without perceptable crossover notch distortion?

Yes I did, admittedly, have an interest in simplifying my system, and going back to solid state after 14 years (with tube preamp); However my tubes are gonna stay :)

To all my solid state friends, please know that I have owned many solid state amps which I have truly enjoyed and have the utmost respect, dating back to the Reference Levinson 32's...and I know there are great SS amps out there, and primarily class AB designs.

Just wanted to share my experience, and learn alittle more about class A solid state, specifically.

With thanks in advance for your thoughts

Brian
audiobrian

Showing 2 responses by audiobrian

audiobrian OP
187 posts
 
Viridian:

Please allow me to clarify...the "buzz" meaning lots of interest, not an audible buzz :)

Thanks
Brian
audiobrian OP
187 posts
 
I truly appreciate the ongoing discussion. Another point of confusion to me is comparing let's say a Belles MB-01 class A and Karan 450 class A both using approx. 1000 VA transformers/channel, similar capacitor banks, and 20 transistors/channel. However the Belles is said to deliver 75-80 watts pure class A into 8, and the Karan, 450 watts pure class A into 8 ohms.......this huge difference in pure class A output power is not easily understood, even though Mr. Belles and Mr. Karan obviously use different toplogies, transistors, etc.

For what it's worth, in the context of my system only, my personal favorite solid state amplifier, which I do own, and alternate with the VAC, is the class AB Gamut M250 monoblocks. As many know, these monoblocks use one large mosfet pair/channel. I'm not sure if using a single mosfet pair/channel is theoretically better than paralleled devices, as Gamut and, I believe, Vitus believe....another interesting topic, perhaps for a different thread :)

My system comprises a VAC Ren mkII pre and either the Phi 300/Gamut 250 into Kharma Midi Grand Ceramiques :)

Thanks
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