[WTB] 70 volt step up transformers

[Mike Caldwell]

I'm looking for four 70 volt step up transformers with either 4 or 8 ohm primary taps, something in the 150 to 200 watt range.
Anyone have a good and clean ones pulled form an install.

 

[Josh Millward]

Re: 70 volt step up transformers

I'm looking for four 70 volt step up transformers with either 4 or 8 ohm primary taps, something in the 150 to 200 watt range.
Anyone have a good and clean ones pulled form an install.

If you don't get anything from anyone here, the Peavey Automatch II is a very nicely priced transformer that will do what you desire. It is rated at 400 Watts, but the extra iron and copper won't hurt anything.

Also, you may want to consider something from Edcor. They make a lot of great transformers at great prices.

 

[John Roberts]

Re: 70 volt step up transformers

Interesting... IIRC the old Automatch was an auto-former, not a fully isolated transformer so the ground on input and 70/100V output was common. This new improved automatch II is a true transformer that install guys like (so they can be sloppy with speaker wiring).

I only bring this up because the OP was looking for used parts. An old automatch will be cheaper even if brand new because auto-formers require less copper and less iron for the same power.

You don't absolutely need to have isolation, but it's good to know what you are buying .

I wouldn't expect to find a lot of used step up transformers since install amps typically have them built inside the amps. While Peavey sold a bunch of automatch over the decades so somebody was using them.

JR

 

[Josh Millward]

Re: 70 volt step up transformers

Peavey sold a bunch of automatch over the decades so somebody was using them.

Yes, I put in more than I care to think about. They were absurdly useful once you understand all the different things you can do with them! I always kept three on my service van plus an old Crown D60 amplifier to fix the "issues" I was often sent out to take care of. Actually... I may still have some in my cabinet at home.

I think I'll send you a PM. I'm pretty sure I have enough.

 

[Mike Caldwell]

Re: 70 volt step up transformers

Thanks for the responses, But I have since found a Crown TP170 four pack that will be perfect in this install upgrade/addition. I looked at the Peavey Automatch and the Edcor models, the Peavey would have been a little over kill and more expensive for this system and the Edcors have about a four week lead time on the order. For what it's worth the Crown TP170's are auto-formers.