Acoustic Elegance AV15

[bumpin buick 5,000+ posts]

maybe its a dumb question but if your looking for that much of a range, why not consider a sealed box?

 

[Papermaker85 5,000+ posts]

buick, i mentioned it because the woofer is going to do well with lower power, i never denied that, but its also the fact thats too low an FS KILLS high frequency extention and output above and below tuning, its simply from the lower Q of the aligment.. you have yet to measure it @ 70 vs the other subs.. which will show hoe peaky the driver is.. if you put hte hw/tnts etc.. in 6 cubes they will do the SAME thing.. peak harder near tuning.. the AV needs tiny boxes, the other woofers need 4-6 cubes.. not a fair compersion... SQ? your talking about output here.lol... they just mentioned that softers spiders are more efficient, but thats souly the subs efficiency, not the entire system efficiency... keep adding power, show how it does as power steps up.. i never said output was poor, i said the spider has issues...

 

[ciaonzo 5,000+ posts]

john is a great guy, i dont dislike him one bit, but above tuning ported acts alot like freeair, compliance and qms are relied on, not souly the motor. thats the reason many spl woofers have such a low vas... i tried telling him before i pushed it hard that the courrgations on my woofer have a different stifness in each set.. i was wrong about the ottermost its actually the very first 2 right next to the former.. onceits reaches a certian throw it just looses all its stiffness.. it didn't do it the first day, after i dropped the box to 2.8 tuned to 32 and played alot of music(5-6 hours riding,stopping checking excursion etc..) i noticed a decline in output above 50.. so much i got nervious and lowered the xover for 70 to 60 then to 50.. it justdidn't sound good above about 45-50 and i noticed excursion above 50 when crossed higher(recheck changed solpes x over points re donesome wiring checked the amps output) it would act like it was unloading..

This is quite possibly a symptom of an enclosure that is either to large for the driver or has a vent with too much area. In other words, grossly misaligned. I've witnessed the same behavior with high compliance drivers when I make EBS/LLT enclosures that are meant for subsonic reproduction only.

If it is a faulty spider, this goes back to John being more than willing to not only please you the best way he can, but to also test the driver to reveal the possible flaw and learn from it to prevent this situation in the future. That would make alot of was said in a negative light between these two threads unwarranted.

 

[Papermaker85 5,000+ posts]

This is quite possibly a symptom of an enclosure that is either to large for the driver or has a vent with too much area. In other words, grossly misaligned. I've witnessed the same behavior with high compliance drivers when I make EBS/LLT enclosures that are meant for subsonic reproduction only.
If it is a faulty spider, this goes back to John being more than willing to not only please you the best way he can, but to also test the driver to reveal the possible flaw and learn from it to prevent this situation in the future. That would make alot of was said in a negative light between these two threads unwarranted.

2.8 to big? bull shit, buick has it in 4.5... i pushed mine way to hard, it needs a recone.. sorry it bottomed way to easily @ 50+hz.. i check and rechecked everything before i assumed it was the speaker last time i installed the AV X... this time im positive that there is NO issue.. i even took a 100 dollar box(built by ME) and modified it to better fit the woofer.

 

[Papermaker85 5,000+ posts]

This is quite possibly a symptom of an enclosure that is either to large for the driver or has a vent with too much area. In other words, grossly misaligned. I've witnessed the same behavior with high compliance drivers when I make EBS/LLT enclosures that are meant for subsonic reproduction only.
If it is a faulty spider, this goes back to John being more than willing to not only please you the best way he can, but to also test the driver to reveal the possible flaw and learn from it to prevent this situation in the future. That would make alot of was said in a negative light between these two threads unwarranted.

a vent with too much area? you mean lack there of stifness? thats what it boils down too...

 

[Papermaker85 5,000+ posts]

on futher inspection, im positive its the glue joint.. the spider reaches about 20mm and then suddlendly moves another 5mm VERY VERY easily.. like i said before a progressive will solve this problem.. im done.. believe what you like...

 

[ciaonzo 5,000+ posts]

2.8 to big? bull shit, buick has it in 4.5... i pushed mine way to hard, it needs a recone.. sorry it bottomed way to easily @ 50+hz.. i check and rechecked everything before i assumed it was the speaker last time i installed the AV X... this time im positive that there is NO issue.. i even took a 100 dollar box(built by ME) and modified it to better fit the woofer.

Or too much vent area, as I said. Low power rated, high compliance drivers do not want to see large vent area when it comes to being pushed hard. They unload exactly as you described.

I don't build anything strictly for SPL purposes so I relent, you have the upper hand from that perspective. I was just putting another possibility out there.

 

[ciaonzo 5,000+ posts]

a vent with too much area? you mean lack there of stifness? thats what it boils down too...

Yes. I know this seems unfathomable to some of you but there is such a thing. You couldn't have too little without also having too much. It's called range.

A vent with too much area will support a very small frequency band (Q), meaning it will unload quickly on either side of tuning but it will be more efficient. A vent with too little area will support a broad frequency band but it will compress. Obviously neither is desirable.

Which one does it sound like you have?

 

[Papermaker85 5,000+ posts]

vent area is no the sole factor in how high or low the Q will be.. you can still get a wide range with alot of port area.. I had john put the stiffest spider he has on, its still very soft.its not the stifness thats the issue... it plays from 26-50 pretty **** loud with a peak from 32-45.. pretty wide, but im not going to go smaller than 2.8 because it really really limits output around tuning and if knocking it down over1/2 ft^3 does help it nothing will... i used many many many different speakers from IDQ to adire to w7s w3 along with alot of others.. even as compliant as the barahma was it never had this issue with 60in^2 of port area tuned to 32 with 3.75 cubes.. kenny had his in 3.5 tuned to 25 with 40in^2 he had the same results..I am looking forward to seing what they do with a single progressive spider.. otherwise im not even interested... the X will do alot better becasue it has less MMS and alot less motor strength(qes and bl^2/re).. i hope john the best, he really is a stand up guy..

 

[Papermaker85 5,000+ posts]

maybe its a dumb question but if your looking for that much of a range, why not consider a sealed box?

ported is superior in nearly every sense.. wider bandwidth better efficiency lowered excursion requirements for a given output... the 2 things that plauge ported are group delay and cancallation.. i take these into account when designing my boxes and there really not an issue,, keep tuning failry low, and port/sub placment ideal for the cabin, not to mention i have a extended cab truck, so its not a factor..

 

[bumpin buick 5,000+ posts]

guess ive just always been under the impression that the frequency range would be wider in a sealed box. Ive never ran sealed but ive been told that by SQ guys before.

 

[T3mpest 10+ year member]

guess ive just always been under the impression that the frequency range would be wider in a sealed box. Ive never ran sealed but ive been told that by SQ guys before.

It's because a sealed box rolls off slower. Unless you tune really really low a sealed box usually gains an output advantage before you reach 20hz. Usually not worth it though. The advantage to a sealed box other than space is that the frequency response is generally alot more even as a sealed box's roll-off matches with cabin gain pretty well in alot of cases.

 

[bose301s 5,000+ posts]

It's because a sealed box rolls off slower. Unless you tune really really low a sealed box usually gains an output advantage before you reach 20hz. Usually not worth it though. The advantage to a sealed box other than space is that the frequency response is generally alot more even as a sealed box's roll-off matches with cabin gain pretty well in alot of cases.

You also get a much smaller enclosure which is really nice too.

 

[dragnix 5,000+ posts]

go IB to have a big *** enclosure that takes up a small amount of space

 

[John_E_Janowitz 10+ year member]

go IB to have a big *** enclosure that takes up a small amount of space

Yes, I agree that IB is the way to go for SQ. You don't run into issues with resonance in the enclosure and you get the most possible efficiency. If I ever get around to doing a system in my S4 I'm definitely going that direction.

FYI here are a couple people using our IB15's specifically for this application:

http://www.diymobileaudio.com/forum/member-product-reviews/52079-acoustic-elegance-ib15-4ohm-car-version-idmax-comparison.html

http://www.diymobileaudio.com/forum/diyma-build-logs/21873-2006-civic-lx-sedan-build-thread-36.html#post685715

I tried to convince bumpin buick to do an IB between the weight room and his theater room at his house there. Then you could have it be dual duty for working out and watching movies. That may be a little too much though. After bumpin buick really doesn't like bass that much. lol Here's a really well documented IB install for a home theater if anyone is interested:

http://www.avsforum.com/avs-vb/showthread.php?t=1149303

John