ive used transformers to take 8ohm to 70v, is there transformers to go to 25v?
Ive searched some, but wantsx to ask.

Are you looking for transformers to place at each speaker? They are not very common. Fred may have some. Here are a couple:

[Link: lowellmfg.com]
[Link: amazon.com]

This might be a good start.
[Link: globalspec.com]

How many speakers?
At what tap value?

All the 25v transformers I see max out at 4watt

It may be easier to just add a small 25v amp?
[Link: parts-express.com]

It would be interesting to know why you're doing anything with 25 volts. Perhaps another approach might yield an easier solution. So... why are you doing this?

For instance, if you don't crank the holy living crap out of an amp, a 25 volt transformer will work perfectly well in a 70 volt system. A 70 volt transformer will work perfectly well in a 25 volt system, but the wattages named at the taps will be wrong (lower than named)... you'll have to set them by ear.

I think he trying to convert an 8ohm amp to a 25v.

capnredfishbluefishonefishobvious,

I got that part. My question was, why? And I suggested that 70 volt transformers would serve perfectly well except the written wattages would not be accurate. But thanks for pointing that out.

Really, it's just a different way of doing the math. Ultimately, the amplifier and wiring are rated for a certain current.

Perhaps he has a building already outfitted with 25v taps/speakers and prefers not to change any of that.
I do not care why, neither should you.

See buzz's answer just before yours. buzz is saying what I'm saying -- you can use 70 volt transformers. But there might be something about what he's trying to do that makes it a problem to use 70 volt transformers.

25 volt transformers are sofa king's solution to a problem. I'm asking what the original problem was to see if we can come up with a better answer than 25 volt transformers, instead of coming up with a place to buy those transformers.

In a pinch one could substitute a consumer grade autotransformer in-wall volume controls for 25V speaker transformers. Years ago, long before one could purchase cost effective in-wall controls, I would make my own using a rotary selector switch and transformer. "In-wall" was a misnomer for my controls because the transformers were too large to fit in a wall-box. The guys at the parts dealership thought I was crazy because I bought those transformers by the carton.

There's buzz for the win! He proposes a more off-the-wall, pun intended, solution than I did!

He shows that this is not a difficult problem if you can't find 25 volt transformers.



Again, why? I just searched and found several models that can be used to convert an amp channel to a 25V source, and several to be used at the speakers.

SFCI,
You can check with Lowell MFg. [Link: lowellmfg.com]

You can pick a transformer that will be 20% or more above your final power taps of all the speakers combined and not the amp power output.

I also have some Rane and other transformers in my stock from jobs if you need one at a discount price. PM me if needed.

An online directory will give you plenty of options & choices. For example, this one comes up as a good source: [Link: iqsdirectory.com]

[Link: atlasied.com]

What is the application?

I have an old Stromberg-Carlson amp that has 25V, 50V, 70V and 100V as well as 4, 8 & 16 Ohm taps. I modified it to be used as a guitar amp, but that can be reversed since I kept all of the original parts. If they want a real retro look, this is perfect.

[Link: lh3.googleusercontent.com]