Unknown power transformer

I wonder if anyone can help me identify the purpose of this tranny.


[oh man. I'm trying to put a pic here from my pc that I've drawn on but I've never done anything like it before, maybe somebody can give me a hint. Do I need a special server or something?

Anyway the link to the pic is at the bottom, you can see the secondary side just before the output transistors and the primary to the left earlier in the circut just above where it says 17-12 sorry for the confusion]


It belongs to an "acoustic 150" guitar amp head built 72-75'. I recall reading somewhere, somebody saying that they had this head, and though it was a tranny amp that it had very tube-like breakup because it was one of the only amps to use an output transformer.

I do own this amp and it sure does break up nicely when pushed but the x-former is located before the output transistors, could they have put it there for the sole purpose of saturating the transformer before the transistors clip?
http://www.itrstudio.com/anonftp/150amp_schem-1712.gif

That's a "phase splitter" transformer, not a power or output transformer. It provides two mirror-image (opposing polarity) signals to feed the two sides of the push-pull output section. It was once a common technique.

Thanks NYD.

Would it have a significant affect on the overall character of the amp, possibly causing the saturation/break-up I'm hearing? As opposed to a similar amp designed without using one.

Reason I'm asking is I'm looking at getting anouther model of 'acoustic' but I noticed it doesn't use the "phase splitter" transformer. I really don't want it if it isn't going to give me the same type of saturation.

Erik.