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Acoustic Elegance SBP15-4 review

34K views 90 replies 24 participants last post by  rockin 
#1 ·
Acoustic Elegance SBP15-4





Fs............21.30hz
Qts..........0.41
Qms........5.35
Qes.........0.45
Vas.........338 L
Xmax.......18 mm
Re............2.7 Ohm
Pe............500 (continuous) (thermal)
Sd.............825 sqcm
Le.............0.3 mH
Bl..............11.1 Tm
SPL...........90.65 dB

The Acoustic Elegance SBP15-4 is the successor to the presently retired IB15 series of infinite baffle subwoofers. Each sub is hand-built by John Janowitz as it is ordered – for those of you who are frustrated from having not received your sub(s) yet, keep this in mind.

I ordered the sub last July from John and was fortunate enough to receive one of the first SBPs that were made. Unfortunately I had the sub sitting in its box since September of last year, but it has since been installed in my car in January 2012. After nearly four months of playing time, I’d be lying if I said I had any complaints thus far.

I know many of you are waiting eagerly on your own pair of these subs, and since it appears to be taking some time, I hope to be able to give you more insight into what exactly you are about to receive. I will say this, it is worth the wait.

It's a bit of a read, but there is much to praise.

Transient response. Despite pushing the sub to its limit, the SBP-15 has never shown signs of lethargy. A good example of this is Brombo, by Brian Brombers and Akira Jimbo. The song consists of a drum set and bass, but I only listened to the first 1.5 minutes in which there is a solo drum set. The pace is quick and the drummer is really slamming on the drums which make for a strong, hard-hitting bass impact from the kick drum. The AE handles this with great ease, never missing a beat. You can clearly hear and feel each separate impact’s attack and decay from one beat to the next. The sub does an outstanding job of playing only what it is told to play and nothing more – there is no overhang or muddiness. Due to its lightweight paper cone and stronger motor (over the IB15), I have yet to hear a song where sub bass accuracy hasn’t lived up to expectation.

Efficiency. Simply because the sub is infinite baffle doesn’t mean it can’t get loud. I am giving my SBP15 the rated 500w. With the right EQ, I have found the sub is very capable of being almost overwhelming – if you so wish to make it. I am no super-heavy basshead, but I have found it surprisingly easy to get a single infinite-baffle 15” to go from a normal listening level to holy-****-turn-it-down loud with very little adjustments.

That said, I’m now going to compare the SBP15-4 to the McLaren MP4-12C. And here’s why: the McLaren is an incredibly well-built sports car that performs outstandingly on the open track, and it is also a VERY forgiving machine. There are so many electronic safety controls you have to purposely turn off to really endanger yourself or the car. Otherwise, if you make a mistake, the technology is there to save your butt. The SBP15 is similarly a VERY forgiving subwoofer. You can, of course, make it sound bad, but that has got to be your ultimate goal. Barring that, it’s hard to make the sub sound bad even with EQ flops. For example, boost it too much and it will still sound clean and composed. It seems counterintuitive, but that has been my experience.

Low frequency extension.
The sub plays cleanly well into the low sub bass frequencies without distortion. A fine example of this is Bass I Love You – the song dips down below 10hz. While watching and listening to the single SBP15 at high volume, there was NO distortion, each cycle is still felt independently and the driver showed no signs of struggle or strain – it was happy doing its thing.

Sub-to-midbass transition.
Since demoing the sub’s abilities, I’ve had numerous listeners give their compliments to the sub-to-midbass transition. As I mentioned above, the SBP15 has no trouble blending seamlessly into your midbass range. Even crossed at 120hz I was surprised at how well the transition blended together.

Summary:

The sub can handle anything you throw at it, from Brad Paisley’s I Wish You’d Stay, to the extreme lows of an organ, to fast-paced, hard-hitting dubstep and everything in between. The kick drum in Alice in Chains’ No Excuses will hit you so hard it is painful. The sub always moves with authority. In Metallica’s One, the double-bass towards the final half of the song are clear and extremely distinguishable – you can hear and feel each full, individual strike of the drum in perfect time. Limit to Your Love by James Blake begins abruptly with absurdly quick pulsating bass, which the SBP keeps up with perfectly. When the pulsating stops on a dime, so does the sub. This song is a magnificent test for any subwoofer, and the sub passes it with flying colors.

As is with any rear subwoofer, without time alignment, lower notes will of course reveal the location. With proper time alignment, this only occurs with drawn-out low frequencies and the great majority of the time you will forget the sub is even back there.



I will summarize this long post to say this: although the SBP15-4 was only my second subwoofer, it will without a doubt be my last.


Here's the sub installed in my trunk:



 
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#42 ·
I thought I would add, these are cheap pillows, probably polyfill type material inside. I've bought a lot of pillows, it's nice to have an assortment for the times my back acts up at night. I took these because they were the cheapest and biggest and the only ones I could get away with sticking in the car without getting too much grief.

It's significantly reduced the need to adjust sub level and EQ for different songs and different generes. What sounds good on rap also sounds good on classical or rock or country. I guess it makes sense. People worry about the backwave in a sealed box, why not in IB. One thing it did was make these IB15s sound a lot more like the W6s IB. I'm only guessing but maybe a reflected backwave is more likely to get through a thin light paper cone rather than the W poly cone. With the W6 it has to get through the poly and two layers of it with an air gap in the center.
 
#44 ·
Maybe one day I will get a straight forward & accurate answer to this imposing question: AE's IB12Au specs claim 18mm xmax, while I'm given 14mm (even research 10mm) for SBP12 specs. Which is true so I can get a more meaningful linear displacement comparison? Does a person have to buy said products to do their own measurements? And I've email this question before to the appropriate company before someone suggest such.
 
#46 ·
Thanks but I overstand that claim. Now the SBP has conflicting info, 10mm but stated as 14mm actual. I overstand thicker top/frnt plate w/bigger magnet. They share most of the same parts but you telling me the xmax changed as such. Ok:rolleyes:, then surface area should be different on one.

I am damn near done researching such simple info thats not given thru said company's site, pdf files, email contact, etc.......

Thanks for trying, IBcivic, appreciate the effort.
 
#50 ·
Still a cheap thing to try pillows that might break up any backwave off the bottom trunk wall when its open. Though if this was the case I'm guessing there would be SOME change with the trunk open vs closed too.

Grab a couple pillows and toss em in. Can't hurt to try! Much! Lol :D
 
#62 ·
Thanks for sharing this thread, it was very enlightening & cleared most of my trivial concerns. For me, it's all for enjoying the journey to enjoying the music. Be well, be safe, & take care of ones ears.:cool:
 
#54 · (Edited)
I think the IB12 (AU12) klippeled around 10mm one way travel suspension limited. I believe it was said this type of distortion is less offensive than BL or inductance.

As far as suspension, it is the limiting factor, these are IB subs afterall. I don't know about the IB12 but the IB15 which I believe shares the motor and spider with the 12 will most definitely do 18mm one way and more. I don't know if it's linear but it will mechanically exceed 18mm. Unless the surround is what limits the 12, I don't see why it shouldn't have the same travel as the 15. I've hit them with 18hz test tones when I first installed them while watching them to get an idea of where to limit volume. I pushed them farther than I was comfortable and they had some serious excurion. The thing about these subs is the sound doesn't seem to change as you turn the volume up. They sound exactly the same at high output as low output. Maybe it's the inductance treatment.

I believe going by BL, xmax was 18.5mm.

I was never aware the SBP subs had less travel. They have more motor strength, slightly lower distortion, same cone and spider and surround as far as I know, only the motor is different. I thought xmax and xmech were the same. Maybe it's time to get John in here to clarify.
 
#64 ·
That hotel scene was filmed near my childhood home. Big news for a small town. Steve Martin and John Candy......classic!
 
#66 ·
Seems like xmax is generally rated by a mechanical property like voice coil overhang, rather than how long it is truly linear.

Not a single speaker Erin has tested on the Klippel has met the claimed xmax, that I've seen anyway.
 
#68 ·
Other than PA drivers, I've only seen 3 drivers meet or exceed their rated Xmax:
JBL Gti660 mid (Erin) - rated as 5.36mm and tested to have 7.4mm
Scan 18WU mid (Erin) - rated as 9.00mm and tested to have 9.1mm
Dayton Ultimax (VC Mag) - rated as 19.00mm and tested to have 21.9mm

Kelvin
 
#73 ·
I thought the v3 IDQ-10 met it's advertised claims...and it has a suspension much larger and roubst than the AE for the same amount of throw.

The Dayton Reference 12 tested here met it's claims of 14mm. I have the 15, and it too has a much larger suspension than the AE 15 I used to have had.
 
#74 ·
To bring this slightly more back on topic.. ignore what I said about the pair of IB15s sounding totally different in my car than the single SBP15 in Ally's. I had the freaking subsonic filter on the amp up which is why I thought mine were lacking in the low lows. It's all good now.

SBP15 is an outstanding sounding sub regardless.
 
#77 ·
I guess this kind of belongs here since we talked about the pillows and other potential acoustic treatments in the trunk.

I just finished redoing my amp setup. I had an HD600/4 and a 900/5 under the driver and passenger seats. I replaced the 900/5 with another 600/4 and installed my oooooold Infinity Digital 300 in the trunk for sub duty. Essentially doubling power on my midbass and subs and more headroom for the tweeters and mids. This old amp seems to have a non defeatable subsonic filter but that's not important now.

With these changes I expected to have to level match a bit, obviously. Once I got it up and running the subs sounded terrible. I checked the lowpass because it sounded like there was a lot of 60-100+hz material getting through. It sounded awful. The highpass was still 50hz/12db just like before. To get it to sound halfway decent I had to bump up the slope and even then it didn't have the same quickness and tightness it had before, it sounded sloppy.

I was about to start playing with EQ thinking the amp had some sort of internal EQ making it sound like this until I saw the pillows sitting on the garage floor. I had forgotten to put them back in. So I put them back in thinking there's no way they're going to make the kind of difference I need to sound decent again. But to my surprise it was a night and day difference, back to how it was before the amp swap and before the pillows were removed.

I don't remember it making this much of a difference the first time when I added the pillows but I noticed a large difference when the pillows were forgotten.

I know this isn't scientific but I'm still surprised how much of a difference pillows can make and I'm guessing it's the backwave reflection making it's way back through the cone.
 
#82 ·
The most noticeable improvement is in the upper sub frequencies. The lower bass does sound richer and possibly louder but that could be from the upper bass sounding better and a lot of "noise" eliminated. It's a huuuuge difference.
 
#83 ·
You have me curious enough to go to Walmart & buy a couple pillows to check this out. ;) Hope I have as good as results as you've had. I will report back.

Actually, I think I'll put a couple towards the rear like you mentioned, & stuff a few smaller ones into the void areas above the rear tire wells.
 
#87 ·
Oh yeah, I've tried just about everything imaginable with the crossover on those subs prior to tossing in a couple pillows. :)
 
#90 ·
I forget what the physics involved is called, but the principle is that as the air in the box compressed, it is heated and becomes 'sticky' and doesn't have the same flow.

This may not be the exact process so if I'm off hopefully someone can succinctly explain it better. (there is one big thread at least on this and polyfill).

Anyhow it has been found that polyfill stuffing in a volume of air acts to reduce this effect Anson effect makes the box seem like it has a bigger volume than it really does. So in IB configuration the attempt is to have infinite volume on one side (or both?). Trunks however have defined volume (unless its cut to vent bnear the sub) thus adding pillows with polyfill make the subs 'think' the trunk has more volume
 
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