Pass Son of Zen w/current sources (etc.)

[Henrik]

Here is some graphs:

[Tyimo]

Grey!

Some more questions about choke loaded SOZ:

-Should I use the inductors instead of the all power resistors from 1 to 6 or only of the 1-2? (numbers are from the original article )
-Need I make the 1 H inductor resistance as low as possible or it is not important.
-Should I use torroid core inductor? I read somewhere that it will not or not so much saturate when the magnetic field gets strong like the classic Iron core inductors. So I would get very low resistance ca.2 Ohm. If I would use an 1H air core, than I would get with 16 gauge wire 5.2 Ohm or with 18 gauge 7.6 Ohm, but both can handle over 300W and I would get the "super inductive power resistor" with much heat like in the original circuit.
-How can I calculate the bias and the needed PSU ratings, heat sinking?

Thanks

[Alain Dupont]

Grey and Henrik

Is this thread finished...

I am currently finishing my A75

and the current sources for the balanced preamp was for me of great interest.

Regards.javascript:smilie('')

Alain.

[GRollins]

Tyimo,
The inductors would replace the Drain resistors only. You'd still need resistors (or current sources) under the MOSFET Sources.
The DC resistance of an inductor should be as low as possible. There's no benefit to be gained from higher DC resistance...okay, maybe the output power would be slightly higher, but not enough to matter. In all other ways, low resistance is good.
The best core is no core. Think in terms of air coil inductors. Any inductor with a ferromagnetic core can saturate. Your job is to keep that from happening. Air doesn't saturate.
Nelson provided graphs for the heat, power, etc. in the SOZ article. Be forewarned, the circuit's a power hog. People were all the time running up against the need for huge heatsinks, etc. and wanting to know if there were ways around the problems. That's why I started this thread--to supply a few ideas as to how to make the SOZ a little more practical.
Alain,
Nope, the thread's not closed. My PC croaked, amongst other things. I am--I hope--on the verge of getting back together with a borrowed PC in the near future.

Grey

[Tyimo]

Grey!
Thanks for your answers!
Tyimo

[Ricdelros]

will it be possible to use this amp in car audio, because this is the simplest amp circuit that I've seen, and I'd like to install it immediately.

[GRollins]

It would work. It would work better still if you used a switch mode power supply to raise the car's voltage up a bit.
In a car you're going to need even bigger heatsinks. Since the ambient temperature is unpredictable and frequently much higher than room temperature, you'll need a healthy hunk of metal to take away the heat.
Might be a good opportunity to use a fan, especially since the operating noises of a car would mask the sound the fan makes.

Grey

[Tyimo]

Hi Grey and Brian!

After 2 years a question: did you build your Follower of Zen variations?
Is it worth to try?

I built a "Follower of Zen" the SEWA V1 from Mad K and it is very-very good. I have some matched IRFP240 and I would like to try a ballanced type like yours.

Greets:

Tyimo