Is it worth it to try and use this "nice" car sub in the house?

[aarond]

Admittedly I think I already know the answer to my main question but for those of you willing to entertain it I would appreciate it. The biggest reason I’m even asking is because I’m away from home for quite a while and I have a lot of time on my hands. Sub is a beefy car audio sub (proven by the specs). I also have the matching passive radiator that goes with it. I basically did some quick and dirty modeling in WinISD and was surprised at how bad the default curves were. I played a little longer to try and “fix” and it just doesn’t look practical regardless of box size.

The biggest inspiration for this concept is the fact that I picked the sub and PR for a good price. Also the idea I had in my head was for a small 12ish x 12ish x ? ("?" Being greater than 12) enclosure that had the sub and PR on opposite sides of the "?" side, an HPSA1000 amp on one 12 x 12 end and an old school Xtant P500 PEQ flushed into the other 12 x 12 end (see picture). I have all of these on hand. All in all I think it would look pretty sweet but unless all the EQ’s (on the sub too) make it doable I don’t think it would be worth the effort.

Sub is a Boston Acoustics SPG555 (4 ohm version) specs are:
Can be found here… http://www.bostonacoustics.com/PDFs/manuals/SPG555Man.pdf
PR can be found here: http://www.bostonacoustics.com/PDFs/manuals/SPGTRman.pdf
Qt .80
Qms 11.66
Qes .86
Fs 31.9
Vas 39.77 liters
Re 3.15
Mms 276.7
Cms 89.9
Xmax 22mm
Sd 555 square centimeters (equivalent to a healthy 12”)
Bl 14.27
SPL eff 83.6
SPL sen 87.7
And for those of you interested in the PEQ… http://www.xtant.com/archives/html/techSupport/pdfs/P500Man.pdf

[johnnyrichards]

High Q drivers and bass reflex do not mix well. You might be surprised at how it models with just a simple highpass with boost or linkwitz transform.

[fusseli]

Most car alignments peak high and roll off early, so then cabin gain takes care of the rest. I'm sure that's the best for SPL in that environment and an attempt at flat FR.

I'd say model it and see what you come up with. Maybe a bigger sealed box would work, then you can EQ the lowend some. That's a lot of xmax to play with, 49mm xmech is a lot also, and a 1000W plate would hopefully be enough to fuel some eq. No reason it can't be made to be used at home... Results will vary though.

[nottaway]

Thats a real nice drive!

It has low sensitivity though and is gonna need lots of power.

Really cool I haven't seen a "modular" drive with removable voice coils, surround/spider and upper basket like that.... The Fs is not too high, some of the Fi audio drives are top choices for HT DIY subs right now and they have Fs in the low 30s.

Probably worthwile as long as you don't have to sink too much in the amp and have PEQ because its gonna require EQ on the bottom.

[XtremeRevolution]

Thats a real nice drive!

It has low sensitivity though and is gonna need lots of power.

Really cool I haven't seen a "modular" drive with removable voice coils, surround/spider and upper basket like that.... The Fs is not too high, some of the Fi audio drives are top choices for HT DIY subs right now and they have Fs in the low 30s.

Probably worthwile as long as you don't have to sink too much in the amp and have PEQ because its gonna require EQ on the bottom.

Its actually a terrible subwoofer, and for the price, there are MUCH better options for both home and mobile (and both) use.

Its not really "modular" but rather "removable," and designed that way for a reason. Image Dynamics IDMax and IDQ drivers have removable moving assemblies for re-coning purposes in case you break one due to abuse. Boston Acoustics took that to a whole new level by making the voice coil and former removable because they burn out very easily.

The sub has very poor thermal handling characteristics, and can only really take 350W RMS before exceeding thermal safe limits.

Here's a review previously made on diyma.com:


Performance wise, you see a typical parabolic bl curve that's heavily offset nearly a cm in the forward direction. Le curve shows that no shorting ring is used. Suspension looks like quite a bit of throw, but again offset. This test barely taxed the limits of the suspension. Unfortunately I wasn't able to test the limits of the driver further; as you can see the driver temperature exhibited an increasing change up to 150 K at about 350w of power. This was the safety limit of the test. Both the motor and coil were quite warm to the touch. This was a first for me, as I find most subs do not exhibit this drastic change of temperature so quickly. Given the t/s parameters of the driver, the large voice coil and replacement system, as well as the very long throw I'd take a guess and say that this driver was designed for high output spl, albeit the cooling is subpar to other drivers that I've tested. Although the driver is well "sinked" with cooling fins, it appears that airflow may be a bit restricted with only small holes along the bottom for venting and no direct exposure to air for the voice coil.

Do some more research on this sub and you'll find that these voice coils are constantly burning up under rated power.

[aarond]

Most car alignments peak high and roll off early, so then cabin gain takes care of the rest. I'm sure that's the best for SPL in that environment and an attempt at flat FR.
I'd say model it and see what you come up with. Maybe a bigger sealed box would work, then you can EQ the lowend some. That's a lot of xmax to play with, 49mm xmech is a lot also, and a 1000W plate would hopefully be enough to fuel some eq. No reason it can't be made to be used at home... Results will vary though.

You were right... I sat down and started modeling again. The curve "looks" much better after applying an HPF (makes the response look less peaky). +4dB @ 25Hz and +2 @ 45Hz makes it almost flat w/ a 3dB down point of 25 Hz and Xmax stays in check w/ 800 watts input (realistically what the HPSA puts out give or take).


Its actually a terrible subwoofer, and for the price, there are MUCH better options for both home and mobile (and both) use.

Its not really "modular" but rather "removable," and designed that way for a reason. Image Dynamics IDMax and IDQ drivers have removable moving assemblies for re-coning purposes in case you break one due to abuse. Boston Acoustics took that to a whole new level by making the voice coil and former removable because they burn out very easily.

The sub has very poor thermal handling characteristics, and can only really take 350W RMS before exceeding thermal safe limits.
Here's a review previously made on diyma.com:
Do some more research on this sub and you'll find that these voice coils are constantly burning up under rated power.
XR, I was aware of the Klippel test you mention before I posted. I’ll admit that it is a notable weak point in a driver of this price point but I think you are overstating it. I did quite a bit of Googling before asking for advice regarding my application. While I did see reports where people had to replace the voicecoils I never got the impression that it was at a rate that was out of line for the typical demographic that this product is designed for. JL’s 13w7 is arguably of the standard in these types of apps and those things are far from bullet proof (probably more durable than the Boston though).
Re Klippel results… here’s some input pertaining to the currently hot topic Aura buy out subs that apparently had issues at only 200 watts during Klippel tests. Worth mentioning? Yes. Worth worrying about? Depends on the user IMO.

copying/pasting myself here...And Nyugen's bit about the inability of the Aura to withstand the testing is scary. BUT, realize the Klippel is like listening to 0dB pink noise at full friggin' tilt for 10-15 minutes. It's not music... it's a stress test