Various amp designs

[FennerMachine]

What are the pro's and con's of the following designs, or if properly designed should they sound similar/the same?

Current vs Voltage amplification

Voltage vs Current feedback

 

[Thompsonuxb]

Wow..... This should be interesting....

 

[FennerMachine]

Indeed...

The reason I ask is that the best overall performing amps I've demoed where a current amp, fixed current with varying voltage, and one using current feedback instead of voltage feedback.

These two amps sounded the most realistic and natural of many amps I've demoed.

 

[drummerman]

Valve amplifiers often swing volts rather than a lot of current, one of the reasons they can sound dynamic and alive with sensibly matched speakers, sounding more powerful than their rating suggests. They can make huge power houses of amplifiers sounding stiffled and boring but on the other hand sound weak and uncontrolled with the wrong speakers.

A lot of current is useful when asked to perform with different speakers and/or speakers which are difficult to drive.

Personally, I think somewhere in the middle is ideal. An amplifier with a decent power supply but not to big and stiff but with ample dynamic headroom.

As always, finding the right speaker for the job in hand is important.

 

[FennerMachine]

Thanks drummerman!

That kind of makes sense.

Maybe that's one reason why amps can sound different.

With a constant resistance they can perform almost identically with a frequency sweep, but under a variable load they could start/stop notes too quickly or slowly depending on the power supply.

Does that sound about right?

Also, could a well designed constant current amp just supply more voltage to give the power the speakers demand, or does it not work that way?