2KW transformer

[barendh]

Hi all,

Want to convert my Outlaw Audio 7*200W @ 8 Ohms final from 115V to 230V power line.
As there were 2 toroids inside, I thought wiring the primaries in series would be an easy solution...not so.
I did not want an enormous step down transformer humming away in my audio rack...

The amp has 7 identical amp modules with their own rectifiers and smoothing, every module requiring twice 25V (29V open).
Turned out the toroids are different (duh!) as one is for 4 and the other for 3 channels...
Diameter is 15cm, one a bit thicker than the other.
They're not potted, but I can't get to the primaries without stripping the entire cores...

Found that wiring an extra enforcement transformer's split primary 0-115-230V across the series primaries works reasonably well, measured in quiescent state the distributed Vpri changed from 75/140 to 110/116V.

First question:
Is there a better way to tackle this, short of buying very expensive high power 230V toroidals?

The amp as supplied is almost impossible to handle: 51 kg!
Dented the stairs schlepping the beast up to my little lab en down again, my wife was NOT pleased...
So my idea is moving the transformers to a second cabinet.
As is, it means making a plug-and-socket cable having 28 leads carrying some considerable current...

Second question:
A. What would be the penalty for connecting all these primaries together so I can have just a 2 wire umbilical?
B. Or should I go for a 2 + 2 wire solution (since every module is fully balanced - requiring twice 25-0 volts).

Thanks for your input!

[mrivera982]

I am new to this however, correct me if I am wrong... +/- 29 volt rails do not provide enough voltage for 200 watts RMS into 8 ohms. Am I missing something?