Bob Carver made amps under the Sunfire brand that had speaker outputs selectable for voltage or current drive. I’m told the current drive was created by the insertion of a series resistor.
Are all amps being built wrong?
The power amplifiers that drive our loudspeakers are mostly built as a low impedance voltage source. They have always been ... but why?
Loudspeakers have a (greatly) varying impedance over the frequency range. A current drive amplifier would eliminate the issues that stem from this varying impedance, and at the same time make discussions about esoteric speaker cables that strive for optimal R, C, L superfluous. Although there still would be these un-measurable ’this (very expensive) cable sounds better’ debates and opinions ... and that’s OK, that’s part of the fun. :)
So ... why are amplifiers not built as a high impedance current source?
This is an interesting read: https://www.current-drive.info/
Loudspeakers have a (greatly) varying impedance over the frequency range. A current drive amplifier would eliminate the issues that stem from this varying impedance, and at the same time make discussions about esoteric speaker cables that strive for optimal R, C, L superfluous. Although there still would be these un-measurable ’this (very expensive) cable sounds better’ debates and opinions ... and that’s OK, that’s part of the fun. :)
So ... why are amplifiers not built as a high impedance current source?
This is an interesting read: https://www.current-drive.info/