Wednesday, May 4, 2011

Replacing the 300 watt amplifier with a 2x25 watt model

The 300 watt amplifier I have for R2-D2 uses up a LOT of power.  It also takes up a fair amount of space inside the body.  Powered by a 12 volt 18 amp battery, the battery life isn't as long as I would like it to be for events that run a few hours long.

Recently one of the other builders posted a link to a very small and modestly powered amplifier on Parts Express

While on their site I checked for something I hadn't found locally...3.5 inch speakers by Pioneer.  I've read good reviews of a particular model for a few months now and it was on my "To Do" list for a while.  They had them so to save on shipping charges, I opted to purchase both.  

And a few days later, they arrived...

I then went to the website to get the installation instructions in PDF format.  With the directions confirming how the setup should work, I setup a test rig...

It works really well!  Since I have an event the next day, I am not going to bother trying to replace the speakers and fabricate a mounting for them.  The existing 100 watt will work just fine.

The existing 300 watt amplifier can now be removed and as you can see with the pictures below, I gained a lot of space back...

Top view, showing the metal stand (heat shield) above the amplifier.

Heat shield removed, now to remove the 300 watt amplifier.
Look at all the free space!

Yes, the wiring situation is a bit of a mess!
After cleaning up that wiring mess, I used some L brackets and some FR4 G10 material to mount the amplifier board to.

With heat no being an issue anymore, I will be able to remove the cooling fan.

After testing various volume settings on the card, I found setting it to LOW wasn't quite good nor was high.  However, through testing with the sound settings on the netbook, its working quite well!