amp recommendation

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I would like to try building a new amp. The son of zen and related designs look very interesting, but since I've never built anything like it I haven't the slightest idea how to start messing with the schematics.

I've done a tube amp that I love and a chip amp that sucked. However, the chip amp required a pretty expensive power transformer that I would like to reuse if possible. It is 225VA, 2x24v. Does anybody have a design that would work well with this power?

I don't have any speakers for it yet, but I will be using full range drivers in a small-ish package (sealed maybe?)

Lico
 
If you are dead set on reusing that trafo then you will have to find an AB class amp of around 60watts/ch. The Pass forum is pretty much geared towards class A operation which generally uses much larger power supplies with lower rail voltages. You should pose the same question on the Solid State forum where you should get many proposals and suggestions. There's plenty of good sounding AB amps out there.

Best, Bill
 
If you want to build a design by Nelson then I don't see why the trafo you have can't be pressed into use. You can build a Class A amplifier with this trafo.

I'm not familiar enough with Nelson's amplifiers to suggest the 'best' one for you, but I would suggest that you choose one with an available pcb (again, not sure of what's available)

One option for a simple amplifier is Zen4, it recommends a 300VA trafo, but if you can accept a more limited headroom and lower bias current you could at least start with your 225VA.
http://www.passdiy.com/pdf/zen-v4.pdf

Or look at one of the Aleph's.
 
225VA 2x24V will do ONE channel of F5 if you add a regulated power supply as per Zen Version 3.
Too much voltage and too little current for 2 channels I am afraid.

If a 225VA transformer is expensive for you, then maybe you should find something else other than Class A.
This is certainly not the only costly item and most likely not the most costly item.


Patrick
 
I agree with Bill.
If it was a 600 VA transformer, I would suggest a regulator to lower the rails to 24V and build an F5. But 225 VA is really not enough, especially if you burn some off in the regulator. And Choke input would help, but spending $50 to use a $30 transformer seems a bit silly. On the other hand, we are silly types hereabouts!

Doug
 
With that transformer (2x24V, 225VA) two channels of F2 could be built with somewhat lower bias - one channel per secondary. Some regulation can be added to lower the voltage to +24V (CRC or active, F3 style).
It's simple, it's class A ...

First Watt: Downloads
 

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That's if you're using split +/-34V rails.

How about ZV4 without a regulated supply? I think that
would get you to 10 watts.

:cool:

This is a really helpful thread. I have a pair of 300VA 2x25v transformers from a chipamp project and would like to use them in another amp if possible.

Which ever amp I decide to build will end up driving a pair of Brines FT1600 MkII (Fostex FE167E) Speakers


Hi Nelson

Will the Zen v4 power supply work as well as the F5 version?

Thanks
 
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