My 2nd DIY Bird sound system

My 1st DIY sound system has been working 24/7 for more than 6 months without a hitch. Now its time to build another.

To recap, my basic system requirements are:
1. High power 4-channel amplifier (100W r.m.s. each). For a small bird house (e.g. a 3-4 storey shop unit), use of 2 channels is more than adequate; the other 2 channels are in stand by - handy without the need to replace the whole amplifier when a channel amplifier failed. I have even chosen those with output short-circuit protection.

2. Back up battery for internal sound in event of mains outage with 2 x 12V, 7AH (more can be added if desired).

3. A 12V DC cooling fan continues to operate in event of mains power outage.

4. Switch-mode power supply (for energy efficiency) to power the sound system & charge the backup batteries.

5. CD sound player with MP3, USB port and SD memory card as standard.

What did I learn from the previous exercise?
The Size 3 enclosure, though adequate, was rather compact to mount two players within. So I up sized it to Size 4. Everything else remains the same.

Two 10 cm fans, one 220V AC and the other 12V DC, mounted at the base.















Seen here a 4-channel (each with 100W rms) amplifier, timer and relay to control the external sound.



















Vertical mounted CD player on swing door.















My neighbor, P'Wah lent a hand on some metal work. He is another DIY man extraordinaire!



















The wired up system undergoing tests - the LED lights looks cool! Forced vertical air cooling; drawn from bottom to exhaust at top PVC vents.



















My external test tweeters mounted in the backyard.



















It turned out the CD players are not suited for vertical mount, so P'Moo re-arranged it back to horizontal mount.



















I have 4 such systems built by now - 2 going to bird houses in southern Thailand. If you are interested in one, please drop me a note here.

July '09 update:
As more of my friends get to know and appreciate my amplifier set-up, P'Jiap has asked me to build him 2 sets. P'Moo will follow suit to convert his amps to wall mount too.