Factory Subwoofer Info Guide

[Murckman]

Got it powered up last night. Not impressed. I have to CRANK the gains to get any meaningful excursion, and on top of that I have a bad rattle to track down. Also my cobbled together sub spacer has bowed and I will have to make a real spacer after all.

Did some post install research on setting the gains via measured voltage, which I'll look at tonight, but it may be that my 4 channel amp isn't suited to this use (go figure . . .). No real issue, amps are cheap now, I just don't want to have the car sitting for four days while I wait on shipping.

Aside from the rattle how does it sound? It might be the amp rattling on the sheet metal since it’s only held in with zip ties. If you have even a small piece of sound deadener you could put some in the back of the amp.
Also your amp might be 4 ohm in which case you are running parallel to a 4 ohm sub with 8 ohms.

 

[grinchy]

What amp and how did you wire it?

Oh. So many tears. It's a Soundstream st4.1000d. The JBL Sub is 200wRMS, 600 peak. I never set out to use this amp for this . . .

Originally, before the Alpine DSP and before sub update, I used an waterfall of three dedicated four channel DSPs, and 3 four channel amps. With the DSP and sub update (which can amplify some of the secondary channels, and which took up space of one of the amps), I was only using two amps (7 channels, 6 + 1 bridged for the sub), DSP powered 5, and I had an amp left over . . .

So the sub was promising bridged, but the load wasn't right for the little amp (4 ohm rated in bridge, 2-3 ohm load on the sub in parallel, and it wouldn't get the watts it needed in series or as a single VC (5 ohm), so . . . I decided why not use that 'spare' amp and install it in the back, and run the sub in the worst way possible, as a dual 5 ohm load bridged (yes, that is bridged on each voice coil, so the amp is seeing two 5 ohm loads, separately). It is basically 'free' (time + an 8 gauge amp install kit), so why not, right?

Sub is happier now, not exactly slamming, but loud enough I'm uncomfortable using it in the neighborhood setting max levels. That's probably about right for the sub anyhow.

I used a 50 hz sine tone and set the power at the amp with 3/4 volume and target watts of 100Wrms per bridged coil (200 W total RMS into the sub). Sqrt(100*5)/sqrt 2 -> 15.8V or so. I don't have an RMS meter, so have to divide the AC voltage reading to match for my multimeter.

Anyhow, I did end up with the gains maxed, so I had that right. Was able to reduce the level in the DSP to 45 of 60 using the multimeter for sanity check to set power, so I have some headroom if I want it to run hot for demo days.

I also ordered a mono amp rated at 320Wx1 into 2 ohm that tested good for $80. I can put the sub in parallel and try that to see if there is any difference. It's an easy sub to power at only 200W, but that is also oddly limiting.

Still have a resonance back there, so apart for one more day so I can make the mounting ring.

 

[grinchy]

Aside from the rattle how does it sound? It might be the amp rattling on the sheet metal since it’s only held in with zip ties. If you have even a small piece of sound deadener you could put some in the back of the amp.
Also your amp might be 4 ohm in which case you are running parallel to a 4 ohm sub with 8 ohms.

Yeah, it's not the amp, that would be too easy. Options are the wires in the box (I dynamatted them, but it *could* be them), the spacer shards from my hackaday spacer (I'm voting this), or just a loose something back there. Haven't been able to pin it down, and will have to drive to the country probably to find it, sub has to be pretty loud to start the rattle, and I live in a residential area. . .

 

[grinchy]

Aside from the rattle how does it sound? It might be the amp rattling on the sheet metal since it’s only held in with zip ties. If you have even a small piece of sound deadener you could put some in the back of the amp.
Also your amp might be 4 ohm in which case you are running parallel to a 4 ohm sub with 8 ohms.

Sorry if my answer was short. You've been super helpful and I appreciate the analysis and thoughts.

Just like all my projects it's lasting on and I was a bit frustrated I couldn't put the seat in and park back on the street to clear the driveway for kids.

 

[Murckman]

Sorry if my answer was short. You've been super helpful and I appreciate the analysis and thoughts.

Just like all my projects it's lasting on and I was a bit frustrated I couldn't put the seat in and park back on the street to clear the driveway for kids.

All good. I hope you get it sorted out. I had half the panels in my truck dismantled for over a week waiting on parts so I know how you feel.

 

[grinchy]

Went back in and adjusted the sub level in dsp up and on amp gained down. Wanted to get some headroom on the amp. Made a spacer from an extra shelf. That fixed two problems, the buzz and the hollow sound. Now nice and dead and no resonances.
How 'hot' should the sub be? Frequency sweep has it about 20 dB hot... I know I'll lose low end to nvh on the road but that seems like a bunch hot? Pink noise has it about 6 dB hot.
With EQ I have about 120db flat on the sweep from 25hz thru 80. That's at the 3/4 volume set point.
Pleasant sounding sub now that it is mounted correctly. Fits in with program material well.
I canceled the order for the mono amp.

 

[grinchy]

All wrapped up. Did a 10 min drive and it is just a touch hot, easy to reduce level via dsp. Leaving for now as I don't have the quarter on yet.

It is spectacular. Highly recommended upgrade. I would guess about $300 all in for just a swap out keeping the ML amp as source. Plus some time...

 

[airforce1]

so am I reading correctly the LC needs a 8" sub while an LX needs 10"?

I have a 2008 LX570 and looking for plug and play options.

Thanks!

 

[grinchy]

so am I reading correctly the LC needs a 8" sub while an LX needs 10"?

I have a 2008 LX570 and looking for plug and play options.

Thanks!

The 2009 LX definitely has a 10" single voice coil. Mine stock ML sub measures out around 7 ohm. I had to make a spacer to clear a vertical basket on the shallow mount replacement. A more conical basket wound't need a spacer, the shallowest part of the box is within an inch of the rim on the top side. You could also buy this for around $20. An 8" to 10" adapter and a 8" may be the easiest solution for fitting.
*edit clarify and expand to be more clear

 

[airforce1]

Thanks Grinchy....this is what is on my shopping list:

1. Shallow mount 2 ohm 8" sub previously mentioned here:

CDT Audio Subwoofer HD-800 CF

2. Adaptor Bracket: 10

Question: has anyone considered a shallow mount 10" subwoofer?

15-MR10D4 - Memphis 10" Shallow 4 Ohm DVC 300W RMS Subwoofer

<p>The incredibly compact S-Class subwoofers can fit where most subs can't, while still providing impressive performance. These S-Class full-size subwoofers are shallow enough to mount just about anywhere. Lots of bass in a small space!</p> <p><strong>Fe

www.woofersetc.com

Image Dynamics IDQS10D2 10" 200W RMS Dual 2-Ohms Shallow Subwoofer

<p>IDQS Subwoofers redefine the performance standard for small thin mount subwoofers. With a very high linear excursion created from the precise motor and suspension design the IDQS Subwoofers provide you with great sound quality, and power handling as we

www.woofersetc.com

BTW, anyone know if there is a subwoofer located at the center channel in LX570 Mark Levinson sound systems? I'm hearing a rattle in that location and I suspect it's a sub going bad. I'm wondering what the specs are and what size subwoofers are compatible?

Thanks!

 

[grinchy]

No sub in the center channel. It's a two way with a passive crossover though, so you either have a cone Delamination or loose screw or loose trim.
I'd recommend a typical shaped basket not a shallow mount. The shallow mount has near vertical basket walls and that is what gets into the box you can run any typical shape 10" no spacer that is up to the depth as long as it has a normal sloped basket.
My install had to be spaced 3/4" because of the shallow mount basket shape.
Sorry I forgot the depth behind the woofer it is earlier in the thread. A bit less than 5". I can vouch that a 3/4 spacer will fit, so you can buy up to 5.5" sub depth of you space.

Just know you won't be driving that two ohm load with the stock amp for long. The stock sub is 7 ohm. That is a big difference and I doubt the ML amp can bridge the gap.

 

[airforce1]

Oh I didn't know the ohm rating was different for the LX.

Would 6 ohm or 8 ohm work for us LX owners?

SB Acoustics SW26DBAC76-3-DV 10" Subwoofer

And is dual 4 ohm equivalent to an 8 ohm speaker?

Home

Pyle PLPW10D Power 10" 1000 Watt DVC SubwooferThe PLPW10D 10" booming 1000 watt subwoofer's design attracts those who love bass. This subwoofer will make your music growl in your vehicle or at home, in any type of enclosure: sealed, vented, or open-air. The black reinforced polymer basket and...

www.parts-express.com

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Dayton Audio LS10-44 10" Low Profile Subwoofer Dual 4 OhmDayton Audio's shallow subwoofers let you put more bass into less space! The new LS10-44 Low Profile Subwoofer from Dayton Audio provides over 10 mm of controlled excursion, for bass that hits hard and goes deep -- even in places ordinary...

www.parts-express.com

"Timpano Audio TPT-SW10 4+4 10" Subwoofer 4 Ohm" from www.parts-express.com!

Timpano Audio TPT-SW10 4+4 10" Subwoofer 4 Ohm

www.parts-express.com

Thanks!

 

[grinchy]

yes, a DVC 4 ohm wired in series could approximate the factory sub. has the advantage that when you want to go to more power /aftermarket amp you then rewire it in parallel to get it at 2 ohm. It's the approach I took.

When you look at subwoofers look for one with high sensitivity (1w/m measurement) and that is targeted for a small box. I'd estimate the factory box at between 0.75 and 1.25 cft. I put five feet of damping on it, and there were a few sections I didn't cover. . .

 

[grinchy]

The spec sheet on the sub I got say:
200 wrms, 800 peak, 2" voice coil.
Dual 4 ohm voice coil
Fs 26.6 hz
xmax 7.65 mm
sealed volume 0.5 ft3
89db at 2.83v/m
JBL Club WS1000
Shallow mount 3 5/16"

 

[grinchy]

I will say that if I'd known this would be so successful I would have invested a bit more in my sub and gotten something like this:
SUNDOWN AUDIO SLD 10" D4 (I didn't price compare)
Sundown Audio SLD-10-D4 4.75" mounting depth
600 wRMS means you can pair it in the future with a moderate priced microamp and really get some tunes rolling. My sub at 200wrms really won't ever be more than a fill sub. Which is fine, but the price gap between $120 (I paid less via amazon warehouse) and $200 isn't so large.

There are several reliable companies in this price range. CDT above is one. Savard, Hi-Q, American bass, NVX etc.

 

[grinchy]

re: the SB acoustics sub - that would probably need a dedicated amp at 82 db serial sensitivity, i doubt the stock amp has the power to get the volume out of it with low sensitivity. Pretty cool sub otherwise. 3" voice coil and 1" xmax in a shallow mount. Only knock on it is relatively low rms rating (300W). Dual 3 ohm is a good load for a 1 Ohm mono amp too.

 

[ChowChilla]

Does anybody know the cu. size of the subwoofer box? Been lookin at this sub
JL 13TW5v2-2
13.5-inch (345 mm) Subwoofer Driver, 2 Ω

and yes is much larger in diameter, but less then 3" deep ( 2.625 in / 67 mm ) I could have a custom ring for it

 

[grinchy]

Does anybody know the cu. size of the subwoofer box? Been lookin at this sub
JL 13TW5v2-2
13.5-inch (345 mm) Subwoofer Driver, 2 Ω

and yes is much larger in diameter, but less then 3" deep ( 2.625 in / 67 mm ) I could have a custom ring for it

The box is maybe 1 cuft. It is longer than a foot, and taller than a foot, but only 5-8" deep.

I don't think you'll have much success with a bigger than 10" frame. The reason is that the sub location is inset into the box, so to get a larger diameter you'll be cutting into the irregular box shape around the mount. Pull your jack access door and look at it . . .

 

[grinchy]

The side dash speakers are a little tricky, probably the most difficult of all the speakers. You will need to trim part of the plastic opening to get the new speakers to fit, and you will need to tap a new hole for one of the screws. If you have a small right angle Phillips that will help with the install. I went with the JBL GX series 2.3 ohm. It made a huge difference.View attachment 2294251View attachment 2294252

Thanks for putting this up. I’d really like to replace these midranges.

 

[Mjones]

The box is maybe 1 cuft. It is longer than a foot, and taller than a foot, but only 5-8" deep.

I don't think you'll have much success with a bigger than 10" frame. The reason is that the sub location is inset into the box, so to get a larger diameter you'll be cutting into the irregular box shape around the mount. Pull your jack access door and look at it . . .

So does the volume enclosure include the volume to the left of the sub where I've marked in red?

edit - I don't have 'my' 200 series LC yet, but looking to purchase a buddy's '16 in next several months and collecting some speaker parts - maybe do some fabricating now. I have a 12" shallow mount Stereo Integrity BM mkV (3.4" depth + 1/8" gap with 0.65 cu in. volume required). I'm considering a used LX ebay box to get the 10" opening and then doing heavy mods and fiberglass with step down spacer ring to get the 12" to fit. I have the mark IV sub in my '80 and love it.