Help with a project needed

[Malium]

Hello to all.

I would like to ask for some opinions, guides and advices to build something.
Now, I live in Croatia, where it is pretty hard to find usable drivers for diy, and when You find it, it is way over priced.
Ebay is not an option, as the postal costs are several times as the cost of the item.
So, I envy everybody who lives in a country that that gives an opportunity to buy good priced diy items...

So, as I am a complete noob, with a really bad need to build speakers, I searched, and searched - and I did not find anything that would be usable for any kind of cheaper projects You are building here guys.
Today, I bought an used Logitech X-530 5.1 computer speakers, just to get my hands on some full range drivers for a good price. So, I have a 10 little full ranges that I would use in a project.

This are the speakers:
ImageShack® - Online Photo and Video Hosting

And this is how drivers look from behind:
http://users.tpg.com.au/malydog/fixits/images/open.jpg

There is no info about an model or producer of drivers on them. Also, google did not give me any clues on what type of driver is it.

So my questions are:

1. Somebody know what driver could it be?
2. Should I expect an result if building an custom enclosure for this drivers?
3. What sort of enclosure would it be?
4. Should I use one or two drivers per box (goal is to build an 2.1 system, not 5.1 as original, I would use the rest of drivers for my next project, and I would also build a custom sub for this project)
5. Should there be some kind of crossover used if using two or more drivers per box?

This speakers would be used on a computer, for music and movies. I know that it is hard to advise anything without proper driver data, but it seems that the data will be impossible to find. The only goal is to have fun building something, to get some experience for future project, and maybe to improve the performance of original speakers.

Many thanks!

[gooki]

If it was me I'd build:

3 drivers per side. One driver running full range. Two drivers run up to the baffle step frequency. Then tweak once built.

[rjbond3rd]

Originally Posted by Malium

3. What sort of enclosure would it be?

Hi Malium,

Are they in sealed or ported now? The enclosure looks sealed from the picture. Perhaps the current enclosure is already well designed?

But the little amp is probably doing some contour filtering. My advice would be to disconnect the amp, and listen to how they sound in the current enclosure with no contour filtering.

You can find at least the Fs of the driver without too much trouble (using the Marchand test tone generator, or any other source of test tones.)

[GM]

These are ~2" wide BW tweeters, so expect a Fs around 160 Hz and the cabs they're in are probably already optimized, so doesn't leave you many options to improve on them, especially if you don't measure their T/S specs.

So, just to make something, find the volume of the existing cab and convert it to a cube to find its width x depth (CSA), then make it ~21.2" long to create a long closed box. Cut out the vent at one end so that its area = CSA. From the other end, measure down ~7.4". Mount one driver above and one below it with the frames butted together at the mark. Add stuffing to 'taste'. You'll need the sub system and associated electronics of course.

GM

[Malium]

Thanks. They are in sealed enclosure now. There is no stuffing of any kind in there, and running in this enclosure, they do not sound so well, to my ear at least. I would guess that they would profit from a custom design, according to their free air performance.
I do not have an opportunity to measure the drivers.

Is there any TL project that I could follow? Or stick to sealed?

Thanks!

[rjbond3rd]

Originally Posted by Malium

Is there any TL project that I could follow? Or stick to sealed?

GM's design (above) is a TL. His advice is always best.

[Malium]

Thanks. I have just realized that. My English is a bit on a week side, so I misunderstood GM`s post (many thanks GM). I will post a drawing to see if I understood this design quite right.

[GM]

Originally Posted by rjbond3rd

GM's ........advice is always best.

I doubt that, but I'd like to think it's useful to someone.

BTW, what happened to the project you PM'd me about awhile back? Haven't heard from you in many moons now.

GM

[GM]

Originally Posted by Malium

(many thanks GM). I will post a drawing to see if I understood this design quite right.

You're welcome!

A good idea. I've been on-line helping with folk's designs for ~15 years now and still haven't learned any Cad programs, though I have collected a handful over the years.

GM

[rjbond3rd]

Originally Posted by GM

BTW, what happened to the project you PM'd me about awhile back? Haven't heard from you in many moons now.

Hi GM, thank you for asking but shame on me, I'm just incredibly slow. I got side-tracked by building a speaker calculator from scratch (I just couldn't grasp things any other way). I hope to have something to show you in a few months. Speaker design is turning out to be about 1000x harder than I thought