Portable Speaker Project Completed

[magudaman]

After a couple weeks of building on and off, and of course waiting for parts to come in I finally finished my small portable speaker project. This little guy is battery powered off of 8 AA batteries and put out 10 watts RMS 18 Max. I use a dc to dc converter to get the necessary 18 volts need to run the amplifier. Overall for a portable application this little guy puts out quite a bit of sound; it’s great for the trips to the beach...and much better than your average boom box. I still figuring out what I should do for a grill; I’m thinking of just using a surplus 5x7 car speaker grill but if you guys have any ideas of what else I could do let me know

The picture below is blurry I know but it an over view of the box:

[magudaman]

Picture of back side of the unit. On/off switch and light, 10 amp breaker, and unused audio pot. You can also see the giant heat sink of the dc to dc conveter. With the load of music at max non distortion volume it plays for more than 2 hours with AA NiMH 2100 mah.

[magudaman]

Last picture; this is with the back removed you can see the amplifier on the left and the Dc to Dc converter on the right. Thanks for looking post any comments on the project!

[Vikash]

congrats. great idea,

[G4ME]

any thought on choosing slightly bigger more efficient drivers?

[magudaman]

On the larger drivers: my orginal designed box was much smaller and couldn't have supported big drivers but some how it got streched it out when i was designing the fit of the electronic area. Now that it is accually completed i see i have lots of extra room in the electonics area so basically I have an oversized box. I thought about making that speaker on the front baffle a mid and then buying a 5" woofer and mounting it on the side. Not sure how well that would work but this current design with my taste for bass doesnt quite do it.

[Dominique]

Wow - great job, magudaman!

I have something very very similar in my mind since some time, but it's not yet ripe...

I just wondered if I'd try a National power amp which works from low voltage and have their own voltage conversion. Some of them are pretty efficient, but I wonder if the sound would still be good...

[magudaman]

Well I would guess the majority of amps would sound some what better because my current amp has a 50 db gain so I get quite a bit of noise if I don’t give a loud enough signal. The reason I went with the amp I did was it was available in a cheap kit. But I am very intrigued with the national power amps as they really seem to have a very broad supply voltage range which is a real plus and eliminates my need for the Dc-dc converter. Thanks for pointing them out to me.

[Dominique]

sorry - I somehow forgot about that thread and didn't check back!

At the moment I am very busy, but I got several data sheets for portable amps here and I'll post more when I'll have mor time for the subject.
If you're interested I could at least browse through my files and name those which appeared most interesting to me for the application, so you could compare the datasheets yourself.

How efficient are your drivers? I looked for and found several at about 93dm/1W, more seems to be difficult at a small size!

Cheers,
Dominique