Which industrial transformer to repurpose?

[ozerik]

This store is in my neighborhood, and their selection is mind blowing, but they're not looking to market these to people looking for a big chunky EI transformer to use in a chipamp power supply.

That's what i'm doing. I've already built a point2point Gainclone that i am in love with, and want to venture into multi-chip and multi-amped territory. Which of those industrial style transformers will fit my needs? Let's imagine that it'll power... a dozen LM3886 chips?

Thank you thank you!

 

[AndrewT]

tra 1976 is a dual primary 24Vac centre tapped.
It will give +16Vdc for running a bank of chipamps.
It would be better put to use powering a balanced F5.

 

[ozerik]

My Gainclone takes 35Vdc. What will less volts do to the amp output?

My project is to build a system to fill a large space above a machine shop with loud music for dances and group-exercise classes. The chipamp route fills my budget needs, and the audiophile quality of DIY amps is just a bonus for me (and the few who seem to care about such things).

The space is acousitcally awkward, so that's why I'm looking at multiple amps and speakers.

 

[AndrewT]

Hi,
the chipamp output varies roughly with supply voltage squared.

Going from +-35Vdc to +-18Vdc will reduce maximum power by ~70%, i.e. from 64W into 8ohms to ~20W into 8ohms. But at this low voltage you can use two 8ohms in parallel to extract ~40W into 4ohms.

For maximum power into 8ohm speakers you need 40Vac to 50Vac centre tapped.
Much better to buy efficient speakers for more volume.