PS AUDIO: I am convinced Bob Carver is a crazy genius.


Paul McGowan writes: He’s given more to our industry than most and always surprises and delights with his innovative approach. His tiny cube amplifier, his miniature room shaking subwoofers and to the point of this post, his amplifier shootout.

I remember back to 1985 when several reviewer challenged Carver to build a solid state power amplifier that sounded as good as a tube amplifier. Bob was just arrogant and smart enough enough to take the challenge and the magazine published the shootout and Bob won that battle easily.

But here’s what’s interesting: he did it by degrading the performance of the solid state amplifier to match that of the tube amp. His method was simple yet brilliant. Gain matching the two amps he placed their outputs on a scope set to difference mode. When in this mode the scope will visually display the differences between the two inputs. You can see an example of this with the PerfectWave Power Plants’ built in scope that displays the differences between the in and out voltages.

Using different musical pieces played on both amps, he masterfully hand “detuned” the solid state amp to match the tube amp and reduce the differences to nothing. The results were that the two amps sounded identical in a blind shootout by the reviewers. I think Bob even tried to capitalize on the publicity by producing a power amp that claimed the same performance – alas, unless Bob personally hand tuned each model it never sounded as good.

The point of all this goes back to our post on Purity and if it is a myth. If one can retune a device to sound more musical (thus no longer pure) and if vinyl records are filters that help digital recordings sound more musical, then what of purity?