Newbie Question: Dual transformers for Zen4

[frankv]

I have what may be a dumb question , but having never built an amp before I am not sure what to do. I am trying to follow the passdiy.com pdf as closely as possible with two transformers.

I have two avel lindberg (250va, 2@18v) transformers. I am not sure on how to build the power supply and hope you guys can help me.

I assume the input of the second transformer is simply wired in parallel to the other transformer. Meaning in Nelson's power supply circuit diagram the second transformer is after the switch, .1UF cap, and thermisistor. I'll then copy the circuit diagram for the second channel to mirror the first on the output side. I know that the ground of the second channel goes to the grounding bridge, but am not sure about the input side.

If I am right are the values for the fuse, thermisistor, and cap the same as what is specified in the diagram?

Thx,
Frank

[frankv]

Thanks for the reply JDev.

I agree this is a great forum and would most likely not have attempted a class A amplifier prior to finding this group!

I'm not so keen on building a second chassis right away..I wanted to keep it simple for the first attempt. I am almost done with the chassis now and can't wait to build the inside...

I'll post pics when it's ready...provided it doesn't blow up

Thx,
Frank

[JDeV]

Hi Frank
Welcome to this forum, the best of it's kind anywhere

Since you got 2 transformers, why don't you make 2 monoblocks. 1 problem of using 2 transformers in 1 enclosure are the additional heat.
Read here: http://diyaudio.com/forums/showthrea...&threadid=7812

When building the monoblocks, you can use same thermistor as in the circuit, but can reduce the fuse size. 2 Mono's are also much more appealing to the eye, in mho anyway. If you really want to use the 2 transformers in 1 box, you are correct by putting the 2nd 1 just in parallel with the 1st 1, that is the primary connections (input).

Best of luck with your 1st project and ask anything, no question are a dumb question.