Trans for LM4780? Advice please.

[safetyman]

I have done a search but after reading thru so many threads but can't get a similar question or maybe it's because I am too noob to recognise it.

Anyway, I just purchased a pair of LM4780 boards from PD and was originally thinking of running it bridged but Peter advice I'll need a balanced source and suggests that I run it in parallel. Now for the EI trans, is one with secondaries of 22-0-22 be right for both the PSU boards or does it need to be 22-0-0-22? And what do I connect to the '0' on the trans?

Apologies if this is too simple a question, but please this is going to be my first project for one who has NO basics in electronics.

[Tweeker]

Secondaries of either 22-0-22 or 2*22VAC would both work. Connections would vary by type chosen.

Running them parallel you might want to use a higher voltage though. 28VAC is about the recommended limit.

[Tweeker]

Apologies if this is too simple a question, but please this is going to be my first project for one who has NO basics in electronics.

I recommend you peruase these gainclone pages.

This site has more general audio and electrical information.

[Peter Daniel]

Originally posted by safetyman
Now for the EI trans, is one with secondaries of 22-0-22 be right for both the PSU boards or does it need to be 22-0-0-22? And what do I connect to the '0' on the trans?

It's better ti use dual secondaries with those boards, in case you have a center tapped transformer, connection was explained here: http://www.diyaudio.com/forums/showt...598#post791598

[pinkmouse]

I use a 30-0-30 with Peter's boards, and I like the sound with the higher voltage, but they do run warm so you need decent heatsinking.

[safetyman]

Originally posted by Tweeker


I recommend you peruase these gainclone pages.

This site has more general audio and electrical information.

Tweeker, thanks for the links. In fact I have been reading up DD's pages and some links to basic electrnoic knowledge. Very interesting and informative. Have to slowly try to understand them as I do not come from neither an electronic or electrical background. Guess there's many more years of reading to catch up on.

Originally posted by Peter Daniel


It's better ti use dual secondaries with those boards, in case you have a center tapped transformer, connection was explained here: http://www.diyaudio.com/forums/showt...598#post791598

Peter, I'll definitely go thru the thread and try to understand what I need to do. Itching to get my hands on the boards and I guess Santa (postal service) is late due to the holiday season. I placed orders for most of the parts with Farnell here, but they are out of stock of everything except for the 10uf caps and the 3.7R 2W resistors. BTW, Farnell doesn't list the 1500uf Panasonic FC caps. Should I go for a value that is one step higher?

Thanks for all the replies, guys.