newbie wants to build portable speakers

[IMtheSupervisor]

Hello,
I'm from Switzerland and I'm new here.
For a school project I decided to build my own DIY portable 2way speakersystem. I already choose the energy source - 18650 3.7V lithium batteries.
My advisor for the essay adept physicist, but he told me i have to try to draw a plan on my own.

Anyway, do you recommend any helpful websites or instructions?

the output should be similar to the Logitech pure fi anywhere..

I'd be very happy about some helpful posts
thank you

[ingenieus]

For drawing speaker cabinets you can try Google Sketchup 8.

How many of those lithium batteries are you planning to use? An amplifier to drive the speakers will need about 6V.

[pinkmouse]

Why not have a look at the Boominator thread. Some good reading there.

[IMtheSupervisor]

Originally Posted by ingenieus

For drawing speaker cabinets you can try Google Sketchup 8.

How many of those lithium batteries are you planning to use? An amplifier to drive the speakers will need about 6V.

I thougt about 6*18650 lithium batteries, they have a great capacity. I already desinged a battery case in Cinema 4D. This way i put them together, the result output would be max 25.2 V. But I can change this if its too much..



i also founde some speakers:
HIGH-TECH-HIFI
i am thinking about the one on the bottom, are these suitable?

and do you know any instructions how to build an amplifier?

thx

[IMtheSupervisor]

Hello

I finished a the complete 3D model and i've choosen the components:

6* 18650 Batteries (3.7V) 2*3 in row (11.1V)
2* Monacor SP-45/4 speakers 40W peak, 20W RMS
1* Conrad 2*40W amplifier module

I also found a 5V regulator, but it is very expensive. Maybe you know some offers from shops that deliver to switzerland?

The amplifier module should be cooled. I thougt about put cooling ribs on it and drill some holes in the case, but my teacher said this affects the resonance and the sound quality. I dont want to build some high end studio monitors, is just want to build some handy, portable and powerful speakers.

Please let me know what you think about this project. Suggestions are very welcome.

Following some pictures of my plan. One wall will be made of 2 layers wood, each 5mm thick.

[ingenieus]

It looks pretty good.

Have you thought about putting the amp module in its own sub-enclosure? Perhaps in one of the back corners next to the battery?

[Saturnus]

The amp you have chosen is a very inefficient amp, and not a very good one either. You can get much better for much less. Any Tripath TA202x based amp (except TA2022) will be much better.

Your batteries will not last very long if you use the Conrad amp you suggest. Probably less than 3-4 hours. Expect at least 12 at maximum volume with a TA202x based amp.

The speakers you have chosen are pretty horrible. They do not sound very well. If you something that small then the SPH-30X/4 is very good.

And if you want something that is cost effective then the SP-60/4 is good. You just need to pair it with a cheap dome tweeter and use a series cap as filter on that.