Help a noob w/ 2 projects (1 Viewer)

[ApoloV]

Hey,
I have two small projects that I'd like to take on this summer and was wondering if I could get some help. Being the poor college student that I am, I am using my parents old Pro Logic system. although I'm missing 2 pieces. I need a Center Channel and a decent Sub.

Now I have found laying around some bare speakers that still work and was wondering if I could use them to build these? I have 2 4" and 2 1" tweeters. I also have 2 6.5" woofers.

Ok, for the Center Channel could I use the 2 4" and 1 tweeter to create a MTM setup? Given the right box design would it sound decent?

And would it be possible to use the two 6.5" in an isobaric (sp?) setup? I'm lookig for something thats 50/50 HT/Music To power this would I be able to use a 50W plate amp that came off an old RCA sub?

I've tried to use Winisd but I dont know the Thiele(sp?) factors for the subs so I got a little lost.

Am I asking too much here?
Sorry if it seems like I'm rambling I've just never built speakers and its appealing to be able to get back to working w/ my hands on a project


Thanks
Apolo V

 

[TimForman]

Do you have a brand name and model number for any of these drivers? If we, at least, knew where they came from (type of application) that may provide a clue. The real challenge is coming up with a crossover for the two-way center channel speaker. Since we don't know anything about the drivers we don't really know where the crossover point should be or the roll off rate. I'm questioning whether an isobaric setup would be the best option for the woofers. If you're trying to get the most umph out them a dual driver ported sub may get better results, or a folded horn if you really like cutting wood.

 

[ApoloV]

I was looking around tryinmg to find some info on these.
The tweeters have an high-pass filter soldered to them
The 4" onlything it has is its power handling stamped on it (50W-80W) the magnet seems to have shielding on it. (I'm guessing this would be useful so I dont have to worry about it messing up my tv?)
Now the woofer, it had a small numberon it and after a little google-searching I found its a Radioshack woofer
with a freq response of 56-6000hz
I dont mind doing cutting.. if it'll help me get a better sub I'll do it


Thanks a lot

Apolo V.

 

[TimForman]

It's a crap shoot on the enclosure size. I'd suggest going with the MTM setup on the center. Get the mids as close as you can to the tweeter. Chances are these aren't exceptional performers so a moderately sized enclosure with a small rear port would likely be a good bet. For the sub, probably a smallish front firing/front ported enclosure. You could go with two separate cabinets but I'm thinking that if you could build something with separate air spaces for each woofer in the same cabinet you may be able to get some decent displacement. Put a 2 or 3 inch port in each air space. I've got some old RS bookshelf spkrs with 8 inch woofs and the ports are 3" diameter, 4" length in 18"x12"x8" cabinets. These are just guesses. You'll have to use your best judgment being disadvantaged by no TS parameters. Good luck!

 

[ApoloV]

Thanks a lot for the help...
One last question..
Looking around at Commercial subs I noticed that the Mirage BPS-100i used dual 6.5" Could that be something I could copy? I know that I dont have all the specs on my woofers but could that be a good place to start on the design of the box?

With your reccommendation, seperate air spaces, so each one would have their own port?

Thanks again for all the help

Apolo V

 

[TimForman]

I've never seen the Mirage sub but it may be what I'm envisioning. I'm not thinking of the push-pull setup, rather having both drivers move in phase. Isolate the chambers and provide each with it's own port each chamber and port being identical in size. If they are in close proximity (same cabinet) you should be able to get good air displacement equivalent to a much larger single driver.

 

[Chuck Bogie]

Suggest that you look over at Parts Express on their projects page. Several folks have been putting together "extreme budget" speakers based on some buyout Pioneer 4" drivers and Onkyo tweeters.