Are all amps being built wrong?

re: Vandersteen's being hard to drive.
I had 2Cs and then 2Cis and 2Ces.  They were the easiest, least fussy speakers to drive i ever owned.  Drive them with a 20 W NAD 3020 that could NOT drive Spica TC or SC-50s.  Drove them with a pair of tiny Lux tube amps.  They are very resistive, basically 8 ohms, and modest sensitivity (87 dB???).


Look at the impedance curves for heaven's sake.  Do they like good amps? Sure.  Do they like highly capable, high current amps? Sure, i guess. Do they need them to make music? Nope.

... why are amplifiers not built as a high impedance current source?

Mainly because speakers are designed to be driven by a low impedance voltage source. When amps and speakers are co-designed though there exists the possibility to use current drive - I believe Bruno Putzeys has done this on his actives (Kiis) over at least part of the frequency band.

Mainly because speakers are designed to be driven by a low impedance voltage source.

Aside from what i already wrote, here's also the practical issue.  A low impedance, hgih current amp will drive anything.  Others might (might) sing with speaker A and suck with speaker B. You know, like lots of high end :-)
I'm always fascinated by this. I cam plug my amp into about anything and it will work very well and sound very good. Will it produce some synergistic, euphonic magic effect? Nope.

Aside from what i already wrote, here's also the practical issue. A low impedance, hgih current amp will drive anything.

This isn't quite correct, just so you know. Try putting your amp on a Sound Lab ESL sometime. That speaker is 32 Ohms in the bass and maybe about 2 Ohms at 20KHz (depending on the position of the Brilliance control). Most voltage source amps tend to sound too bright on this speaker; they struggle to make power at bass frequencies. Its MO isn't based on the Voltage Paradigm. Anytime you mix the two paradigms (Voltage and Power) you are at risk of a tonal anomaly.


SETs and other zero feedback tube amps are not meant to be used with difficult speakers (and I argue that no amp should be used with such speakers since the last thing you want to do is make any amp work hard for a living- it will make more distortion which is audible). So no amp can really work with all speakers.

Because a current drive amp is only useful with a speaker that has a flat impedance. Otherwise the amp will act as a tone control and follow the dips and peaks of the speaker's impedance curve. This can hardly be called "accurate"!