diyAudio (
-   Solid State (
-   -   battery power suplpy for power amplifiers possible? (

tschrama 23rd April 2002 06:16 PM

battery power suplpy for power amplifiers possible?
Hi everybody,

I would like to know your opinion about battrey power supplies for a power amplifier (in this case a JLH 10 Watt Class A) ..

Is it a no-go .. or is it indeed possible?



jam 23rd April 2002 06:28 PM

Yes, it is possible but current draw will be very high and you will need to use some huge batteries. I would stick to a conventional supply, possibly with regulation if you need low ripple.


kiwi_abroad 23rd April 2002 08:16 PM

My first successful amp was the 20W Class A amp designed by Douglas Self and published in Electronics World Magazine. As an experiement, I brought 4 cheap 2nd hand car batteries of medium size, and hooked them up to produce the +/-24v (nominal) that the amp needed.

The Amp drew 1.6A quiescent per channel for a total of 3.2A The batteries lasted approx 4 hours before quitting One battery had considerable less capacity than the others, and always went first, I think because it was old. It was nice to have complete absence of hum and noise. The experiement didn't last more than a fortnight, Even I grew weary of 4 car batteries in my room.

I think if you were going to go this route, do it properly and buy some serious batteries, perhaps truck batteries, that would not be anywhere near discharged after a few hours listening, as automotive batteries are not designed to undergo periodic deep discharge and then charging. (They are designed to provide a huge hit of power to start a car, and then provide no power as the alternator powers everything when the engine is running).

Also, you'll still need a power supply to charge the batteries, and you have to decide if it will simply charge the batteries with the amplifier off, or if it will be able to power the amp and charge the batteries at the same time. Note that batteries do not act like capacitors, and provide no smoothing of power supply noise. Charging four large batteries in a reasonible time takes a fair amount of power.

Cheers, Adrian
Hope this gives you something to think about.

All times are GMT. The time now is 08:57 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 18.75%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio