F5 power amplifier

The reason why I was confused was that I recently saw a circuit from Kaneda where he uses real output current (i.e. sensing resistor in series with load) as feedback.

Then I remebered seeing the term on the AD844 datasheet, and Google sorted the rest out for me.

But as Nelson said, the term as used by the chip companies is misleading. The way Kaneda is using it is true current feedback.

Being impatient, what about DC stability and noise performance in this implementation -- 2 well-known drawbacks of "current feedback" opamps ?


Patrick
 
EUVL said:
I am not sure which part of the circuit you are referring to is current feedback.

Anyone care to explain to me, Tino ?

Patrick

Hello Patrick, well I use this term (appropriately or not, I don't know) for feedback connections which go to emitter/source node of the input.

I see a unity gain CFP as 100% feedback ("current feedback"). But I don't want to start a semantic dispute, there is at least one big thread here from 2-3 years ago about this.

Tino
 
Formerly "jh6you". R.I.P.
Joined 2006
I’m really interested in this F5 because the basis is quite similar with my BaboZen (Papa’s Z5 with input JFETs), and particularly because I’m happy user of the excellent sound of BaboZen. It would be a very simple work for me to convert my BaboZen into this F5 if I count only the number of components I should replace.

Hmm . . .

Unfortunately, however, my BaboZen is at home while I’m away from home across the sea . . .




:angel:
 
Nelson Pass said:
Now I've done it. The F5 isn't even out and some of you will
already be scrambling to build the two balanced versions.

:shutup:

;)

To Steen: I guess you are already done with the chasis, heatsinks, PSU.....just waiting for the final schematic, and..we can expect the comment about F5 next weekend? :) :D

Nelson, thanks a lot. It is a joy to have something fresh.
I guess that the sound iof F5 is similar to that of SoZ, but with a lot lower distortion...
By the way, what is its output impedance?

Best wishes and get well soon...
:cool:
 
The one and only
Joined 2001
Paid Member
EUVL said:
> Being impatient, what about DC stability and noise performance in this implementation -- 2 well-known drawbacks of "current feedback" opamps ?

It seems quiet and stable enough. Of course the actual circuit has
temperature compensation for DC stability and also implements
some current limiting (which you can ignore if you like).