Are all amps being built wrong?

Unless I misunderstood what you tried to say ... I thought linear with current.

Nope. Well, linear is probably the wrong term. Proportional is correct. The output of an ideal driver in dB would be directly proportional to the output in db Volts of an amplifier.

That is, if you increase the V by 3 dB, you should measure 3 dB more acoustically regardless of the final speaker impedance (i.e. drivers + crossover).

Of course most speakers are not ideal and compression artifacts occur but this is the goal so long as we are not overdriving the speaker.

This is also why equalizers work. :) If you reduce output by 6 dB at 40 Hz in your EQ then your speaker’s output will be reduced exactly that much. Because everything is proportional to voltage.

PS, db Volts is calculated this way:

db = 20 x log( V original / Voltage now)

So doubling the amplifier voltage = 6 dB louder in both voltage and sound pressure level (SPL) so long as everything is not over driven.

It is proportional to current.
Just they shove it across a resistor and use voltage amplification from the microphone.

On the output side. the driver is not very linear to current.@rudy It was all cool into the cable impedence was mentioned. 

If it sounds good that’s all that counts. Coda was a pioneer in high current and still do ,120 amps on tap short term , huge regulated power supplies doubling down in power as the impedance drops with a very low noise potted 3 KVA transformer ,not many out there can match this especially at any decent price range ,
made-in USA  10 year warranty and very competitive with anything 
In its price class and above.

What about the Magtech…

http://sanderssoundsystems.com/products/amplifiers/magtech-amp

The answer is economics. Amplifiers are voltage sources and practically all speakers are designed around being powered by a low impedance voltage source. Change the output impedance of an amplifier and then it sounds better with some speakers and worse with others. The industry is not going to get together and do an Avalon-Spectral-MIT marriage of specification. The ones making current source amplifiers are mostly the ones making active speakers. In short, to optimize a current source amp you must convince the speaker maker to tailor his specs to your amp. Not gonna happen.