Help wanted to find a suitable transformer for RT1000i Subwoofer Amplifier

Outta_Ctrl

Hey all,

I had a transformer die on one of my RT1000i towers. There are no model numbers printed on the transformer. I know the transformer steps 115V down to 40V with a center tap. I don't know what the amperage the replacement transformer should be rated for. I believe the bottleneck for this amplifier board is the LM1875 chip which is rated for 25W.

I've already spoken with Polk CS a couple of times. They have yet to email me an update.

Any help would be appreciated.

F1nut

Maybe this will help.

Outta_Ctrl

Thanks F1nut. I have looked up the sticker on top to no avail. Underneath the brass-colored casing which holds the transformer to the plate, there is a small piece of paper but no visible writing on it. I'll give CS another call.

Outta_Ctrl

Here's another way of thinking about it. The limit of this board is the LM1875 rated for 25W and the two large caps are rated for 25V apiece. Power = Current * Voltage; therefore with 25W of power and 25V max, the circuit should draw only 1A of power from the transformer at peak. If I am thinking about this the wrong way and the voltage I should be thinking about is really 40V or 50V, then it will require roughly half as much current. So I should be safe with a transformer rated for 1A.

CS told me to go call Midwest Speaker Repair.

tonyb

You could probably buy a whole nother speaker for 100 bucks, grab one out of there . Just sayin'...sometimes easier than chasing down old parts.