I don't know if this is the right forum, but I recently converted my Behringer Thunderbird practice amp to battery power. I like the tone of the amp, and I wanted to play with unplugged acoustic guitarists "around the campfire". This seemed to be a better option than an ABG, which never seem to be loud enough to play with 6-strings.
The conversion was fairly straightforward. The Thunderbird uses the LM4701T power amp, bipolar at +24V and -24V. I purchased 4 of the cheapest 12V gel-cell batteries from Zap Batteries for less than $30, and mounted them in the bottom of the cabinet. I attached a pic to this post.
If folks are interested, I can post pics showing where I tapped into the circuit board to provide switched battery power. The power supply recharges the batteries when the amp is plugged in. I haven't done extensive testing, but I think the batteries last about 4 hours this way. It would probably charge better using a 48V electric scooter charger.
I also bought a 48V golf cart battery gage off eBay, so I can monitor the charge on the batteries. That, and the extra power switch, are the only differences on the outside of the amp. Of course, it's a lot heavier with those batteries in it, but it isn't what I'd call heavy.
I haven't played with my acoustic friends yet, but I'm confident the amp will work for that purpose. I'm pretty satisfied with how it turned out.
If there is interest, I will gladly discuss the details of this project.
The conversion was fairly straightforward. The Thunderbird uses the LM4701T power amp, bipolar at +24V and -24V. I purchased 4 of the cheapest 12V gel-cell batteries from Zap Batteries for less than $30, and mounted them in the bottom of the cabinet. I attached a pic to this post.
If folks are interested, I can post pics showing where I tapped into the circuit board to provide switched battery power. The power supply recharges the batteries when the amp is plugged in. I haven't done extensive testing, but I think the batteries last about 4 hours this way. It would probably charge better using a 48V electric scooter charger.
I also bought a 48V golf cart battery gage off eBay, so I can monitor the charge on the batteries. That, and the extra power switch, are the only differences on the outside of the amp. Of course, it's a lot heavier with those batteries in it, but it isn't what I'd call heavy.
I haven't played with my acoustic friends yet, but I'm confident the amp will work for that purpose. I'm pretty satisfied with how it turned out.
If there is interest, I will gladly discuss the details of this project.
