Hi everyone I own a pair of infinity crescendo cs-3009 speakers. Each cabinet has two 10" woofers, a 6" midbass, 4" midrange, and a 2" tweeter. When I popped out the woofer the cabinet was bare wood. Echoes something insane in there. Also up towards the top of the cabinet it's empty too besides the tubes that the speakers sit in. First question is should I line the walls with foam for the woofers and secondly that empty cavity directly behind the tweeter should I fill it in with loose polyfill? And lastly the mids how packed should new poly fill be in the tubes? Here's links to my imgur pictures.
http://i.imgur.com/dC0xSHZ.jpg
Imgur: The most awesome images on the Internet
http://i.imgur.com/U49JbQE.jpg
http://i.imgur.com/dC0xSHZ.jpg
Imgur: The most awesome images on the Internet
http://i.imgur.com/U49JbQE.jpg
Can you post a picture of the tweeter?
Foam is not a very good damping material. Use wool or cotton felt or fiberglass or cotton insulation. Are the woofers sealed? In which case you could fill the space with well teased acoustastuff or other polyfluff derivative.
dave
Foam is not a very good damping material. Use wool or cotton felt or fiberglass or cotton insulation. Are the woofers sealed? In which case you could fill the space with well teased acoustastuff or other polyfluff derivative.
dave
Have you considered lining portions of the inner walls with damping materials - something like dynamat, in addition to the fiberglass, denim or polyfill suffing? Something like dynamat would damp out wall vibration and reduce image smearing due to resonance. Amazon has a number of options for damping materials like that.
Multi-layer Sonic Barrier is what I use. So do some high end manufacturers with all aluminum construction. 🙂
Reply.
No they are ported, yes I'll post more pictures on imgur. The whole speaker is a rectangle 15" deep, 1ft wide, 47" tall. two 10" woofers on the bottom then the 6" Midbass/ 4" midrange are above the woofers in their own tube enclosure, the midbass tube runs to the back & the mid-range is only about 5" deep. There's room running on either side of the "tube" enclosure for the midbass to the top where there's just an empty space, which is being the tweeter. Obviously I don't worry about damping the tweeter it's sealed but I don't know if the bass is affected by this space.
No they are ported, yes I'll post more pictures on imgur. The whole speaker is a rectangle 15" deep, 1ft wide, 47" tall. two 10" woofers on the bottom then the 6" Midbass/ 4" midrange are above the woofers in their own tube enclosure, the midbass tube runs to the back & the mid-range is only about 5" deep. There's room running on either side of the "tube" enclosure for the midbass to the top where there's just an empty space, which is being the tweeter. Obviously I don't worry about damping the tweeter it's sealed but I don't know if the bass is affected by this space.
Series production speakers are usually scrutinized before to hit the market, if they didn`t put any wool/polyester fill there, then perhaps they though it sounds better this way. Most people think that there should be to any wall, indeed it does the same job if just stuck in the centre of the enclosure in a very random pattern (as most manufacturers do, right behind the driver). This is a very cheap material, especially in large quantities, noone would cut cents out of it.
I would rather put more effort in updating the crossover. The 100uF midrange cap is an electrolytic, better to go for polypropylene here (yes, costly). Remove the lamp/fuse before the tweeter 8uF cap, remove the two diodes right before the tweeter.
I would rather put more effort in updating the crossover. The 100uF midrange cap is an electrolytic, better to go for polypropylene here (yes, costly). Remove the lamp/fuse before the tweeter 8uF cap, remove the two diodes right before the tweeter.
I've worked on those. They came with a good bit of white polyfill, but not stuffed by any means. They are superb speakers by the way. They measure extremely well and sound great to my ears. They could use a bit of cabinet damping/reinforcement I guess, but they sound fine stock too.,
Yeah from what I've seen is the only poly fill in the cabinet was poly fill sheets in a "U" shape behind the top woofer just lining the sides & cross bracing. Nothing on the back wall for the top/bottom woofer. The tube enclosure that the midbass sits in isn't as wide as the entire enclosure & I remember fill being there but I think it was minimal & just to prevent the mid range & tweeter cables from rattling. So I don't want to change it for the worse but do you think 1 thin single sheet of poly sheet lining the walls back/sides would benefit them or change the tuning of the box?. If anyone wants to help me maybe messaging me on facebook would be easier to send pictures & talk about things to improve the speakers. Look me up my screen name on facebook is Brian.dumm.5 if anyone is willing to possibly help. Also I bought a new amp & my low & high end has drastically improved
Best is to find someone from your time zone. My two cents - don`t go insane on spending lots of money on upgrades, they rarely pay off the money spent. If you want to reduce wall vibration, best is to apply sheets of bitumen foil or the dynamat damping type of stuff (many companies manufacture it, I suspect it to be a mix of bitumen with flameproof dust to prevent it from burning your car under the right conditions). Add them to all walls you can reach, they`re cheap and effective. You can add some small pieces to the driver baskets too, they`re standard steel, not cast. Geta a set of spikes, if these don`t have them and decouple them from the floor. Upgrade the crossover as suggested above. I won`t fiddle beyond this point as cost would get you close to building a kit from modern drivers that will outperform this one by a good margin. You decide, of course.
Well the only thing I want to "fix" is the loose polyfill stuffing that was behind the midbass (200hz - 800hz crossover) & the midrange (800hz - 3000hz crossover). Should I follow the 1pound per cubic foot or less/more for speakers that play 800hz & up? I have a computer and a microphone with R.E.W. can I use that to tune how much poly fill? Seeing that these original speakers were designed for these crossovers & cabinet i wont change anything other than the polyfill in the mids
Bitumen lining will deaden the enclosure contributing to the imaging. I would do it if I was you. You can replace the polyfill behind the mid with natural wool or cotton as suggested above by Dave, they have better damping properties compared to polyfill at higher frequencies. The cones look like mica-filled polypropylene, if it is very thin, it would benefit from better rear wave absorption.
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