Two amps, one pure class A, other A/B

The flabby bass is most likely a result of an impedance mismatch. If the two amps have similar impedance curves in the bass region, then the flabbiness will be apparent with both amplifiers when driving the same speakers.

IMO.

Sashav I apologize for hijacking your thread .

Can anyone describe the difference , in sound , between class A and class B ?

Thank you .

A prime example of this is the Forte Model 4a and the Forte model 6. The intended design was the 4a outputing 50w in class A and sounding smooth as silk. The marketing guys at Forte felt is would be easier to market and sell a 250 w amp (125/side class A/B) than a 50 w amp, and demanded the higher wattage version. Both were reviewed in Stereophile, the reviewer prefering the 50w model 4 (the "a" model allows for balanced inputs) to the model 6. Closer matching of the output transisters was needed for the 4 vs the 6, but other than that and the wiring, the parts between the two models were identical. The class A model 4 runs warmer of course. Check out the review. Happy Listening

It depends if one's a Carver from the 80's in Class A, and one's a set Marantz Mono's in AB, I'd go with the Marantz. It all depends. A/B is the ultralinear circuit, which has slightly lower losses and higher power. Class A has slightly less efficient power, higher lossyness in the circuit, and a lot of the time still makes better sound through brute force.

My little Marantz gets just as loud in Class A mode (25 watts) as it does in A/B mode (95 watts) , even though examples have been measured at 105 watts in A/B. Also sounds a heck of a lot better in Class A. Kid Rock sounds better (?) in A/B , Miles Davis sounds better in Class A.