Science Fair Project... (1 Viewer)

[derekBannatyne]

My friend and I are doing a science fair project together, and recently came up with a new idea since our old one crashed and burned. We were originally going to test housing structures under variable wind speeds, but have a new project in mind. We're going to be constructing two pairs of speakers, both with the same internal volume (1.717ft^3) and using these 4" woofers and these 3/4" tweeters, along with this cheap 4500hz crossover. We're going to test whether or not the shape of an enclosure matters if the volume remains the same. The size of the first enclosure will be 6(W)x10(H)x8(D), and the second will be 8.25(W)x16(H)x4(D). The second pair will be designed to be put inwall, to reduce the negative effects of conventional inwall speakers. Will this project turn out alright? We've already ordered all the parts and I'll probably be constructing the enclosures sometime tomorrow. How would we connect the speakers to the crossover, then to the terminals and how much power would these be able to handle and what's the impedence? Also, would these sound alright? Thanks for the help.

 

[Rory Buszka]

If you're using a stock pre-made crossover, don't expect an audiophile result. It should be okay enough. Be sure to post up pics once you've got them done. The crossover is designed for an 8 ohm woofer and and a 4 ohm tweeter. I'd instead recommend, if you're limited to stock crossovers, the 260-146 crossover. It's more expensive at $20 each but you're more likely to end up with a result you can bear listening to. Be careful on your depth with the in-wall speaker mounting. Be sure that the entire mounting depth of the driver will fit within the space you've left yourself. The final speaker would be an 8 ohm load, fine for most receivers.

 

[derekBannatyne]

They actually sound really good, about as good as my Athena Point 5 speakers. Even just two of them seem to fill up my 25x15 basement. I was expecting them to sound like crap, but they sound pretty good and look nice too.
http://photobucket.com/albums/d43/de...=100_07071.jpg
I was worried about the tweeter not being flush mounted having a really negative effect, but they seem to be fine.

 

[Rory Buszka]

That tweeter is set too far back in that enclosure. Ideally, the curved edge of the plastic flange-thingy is supposed to match up with the front edge of the baffle. If you decide to re-build the boxes, figure out what the difference is and then use a router or something to take off material from the back of the baffle where the tweeter is to mount. Then it will sit flush and you'll avoid response anomalies.