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Amplifier Differences


Well-Known Member
In my 5.1 set up I am currently using the B&K Amplifiers in my set-up.

B&K 125.2 (125W 2 channel amp) FR and FL

B&K ST3140 (140W 3 channel amp) RR, C, RL

How does the B&K Amplifier topology/layout and the Parasound below, effect perfomance?

Parasound HCA-1000A (125W 2 channel amp) (I have one of these not in my system)

After reading The Amplifier Myths post it appears that both the B&K are differential amplifiers. You indicated that these types of amps just use part of the cabinet/enclosure of the multi-channel amplifiers.

The Parasound, however appears to be 2 discrete amplifiers that are symmetrical on the PCB and the enclosure.

So, I do have the opportunity to swap amplifiers in my system to see if there is any audible difference in sound. However, I am curious to pick your brain/experience on the topology of these amps and the performance benefits and/or downfalls.


Well-Known Member
Transistor amplifiers tend to be more similar than different. Differential designs are worse, distortion spectra-wise than amps which only have push-pull output stages. The physical arrangement of the amplifier has little to do with how it performs; the electronic differences are the ones that count. Without a schematic diagram of the amplifier circuits (good luck getting one of those), it is pretty difficult for someone not knowing what to look for to tell much about the circuits.

The differences between a transistor amplifier and a tube amp, especially a SET tube amp, are more substantial.