Which industrial transformer to repurpose?

ozerik

Member
2009-08-03 9:08 pm
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!
 

ozerik

Member
2009-08-03 9:08 pm
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.
 
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.