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New Science of Speed Subwoofer and Box Review and Install

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After much anticipation I got my Science of Speed subwoofer assembly and installed it today. For more information on this system see this thread.

Inspired by D’Ecosse’s and Malibu Rapper’s excellent stereo install write ups, and a promise to Chris of SOS that I’d do a comprehensive review, I decided to try a DIY/product review all-in-one.

Just a little background history, I had installed my system about two months prior, using D’Ecosse’s DIY install as my bible. It basically consisted of:

Alpine CDA-9833 Head Unit
Dali Carbonfiber dash
Rockford Fosgate P162S Punch Series 6.5" Component Speakers
Rockford Fosgate Punch P4004 Amplifier
Custom Amplifier Enclosure in the trunk where the tool kit (removed) used to sit.

As you can see I had no sub and while the stereo sounded great, it was way too high and needed some serious bass. I searched and searched and couldn’t find a box that I felt met my needs. Due to horror stories like this one that Malibu Rapper went through, I was very wary of what was out there. Enter Science of Speed with their new audio system. It fit the bill perfectly and having ordered from SOS in the past, I knew it had to be quality. I immediately called up Chris and within in a week the sub and box was in my hands.

I just need to mention what a class act the entire SOS crew is. They not only were informative, responsive, knowledgeable and friendly but they went out of their way to help me get my grubby little hands on this sub. They shifted work around to get the sub box completed in time and they even expedited it to me at no charge just so I could do the install this weekend! Thanks again guys!

Ok now to the write up. Below are a few pictures of the actual sub. You can get more details on the actual ratings of the sub from SOS. For what it’s worth, it felt very solid and well built.

subwoofer%20002.jpg

subwoofer%20003.jpg


Below is the picture of the box. The quality was excellent. No cracks or holes anywhere. The box felt very, very solid and well put together. What I really liked about it was it had some sort of black rubbery surface coating the entire sub. It felt good and it made it feel very well sealed. It also made it easy to screw into as well.

subwoofer%20008.jpg

subwoofer%20012.jpg


The guys at SOS thought of everything and the entire kit came with everything you need to do the install. Also included were instructions and a speaker grill with mounting tabs. They even thoughtfully provided fiberfill for the box, saving me a trip to the store.

subwoofer%20005.jpg


Ok, now to the install. I had already removed the existing subwoofer by following the service manual. It was pretty easy: just disconnect a few harnesses and remove three bolts. Below is a picture of the foot well with the OEM sub removed. The orange wire is the subwoofer speaker wire that I pulled through the car from the amp. *Tip: make sure you give yourself a lot of extra slack on this wire (at least 4-5 feet). You’ll thank yourself later.

subwoofer%20006.jpg


To install the new SOS sub you need to remove/relocate a few parts. The first thing you need to do is detach the yellow wiring conduit from the blue channel. I found it was easier to detach the blue channel from the floor first, then remove the yellow conduit. The blue channel is held in by white tabs that either need to be squeezed to release or rotated. The tabs circled need to be rotated, the ones with the arrow need to be squeezed. One you get the blue channel out the yellow conduit is held in by more white tabs. I found the easiest way to remove them was with a flat blade screwdriver. Insert into the side and push the tab in a bit. Then twist the screwdriver and the tab should pop out.

subwoofer%20006a.jpg


Once released, you need to relocate the yellow conduit so that it runs along the top of the foot well and out of the way of the sub box instead of on the bottom. There is plenty of slack in the line to easily wire tie it to other things under the dash. You just need to get it out of the way so it doesn’t get pinched. Here you can see it tucked under the dash and out of the way. I tucked the left side out under the center console, but I left it out so you could see how to relocate it. Once the yellow conduit was of the way, you’ll need to remove the metal brackets that held the existing subwoofer. This was probably the most challenging part as they are attached by strong adhesive. SOS recommends using a chisel and mallet to remove them. I used a combination of a screwdriver, hammer, Dremmel and vice grips to remove them. Just muscle them out as you won’t need to them anymore. There are three you need to remove as indicated by the arrows. Once those are out, remove the black cross bracing along the foot well wall, by removing the three bolts holding it in. There are some more brackets under the cross-bracing that you can remove using the chisel-mallet technique, but I got lazy and left them in.

subwoofer%20014a.jpg


Next, I drilled a hole in the sub box to run the wire through using a .25” drill bit. There was no instructions on where to make the whole so I just picked some random spot.

subwoofer%20020.jpg


Then I ran the speaker wire through the hole. I found that using some WD-40 or silicone spray first and some needle nose pliers made the job of running the wire through much easier. *Tip: Make sure to pull through enough wire so that you can wire the sub comfortably outside the box. I gave myself about a 1.5’ so that I could lay both the box and sub in the passenger seat without any problems.

subwoofer%20022.jpg


As recommended by SOS, I used some hot glue to fill the hole. SOS said not to use a silicone based sealant since it would not stick to the wire coating. I ended up just globing hot glue on the inside and outside of the hole to make a nice airtight seal.

subwoofer%20025.jpg


Then I wired up my sub. Since the sub has dual 2 ohm coilovers, you need to decide if you are going to wire it up in series (for a 4 ohm load) or parallel (for a 1 ohm load). I chose to wire my sub in series to keep my amp running cooler. Since the amp is in the trunk, which is known to get notoriously hot, and I live in Las Vegas, I decided to play it safe and keep my amp as cool as possible. Wiring the sub in series is easy. I just had to wire the negative of one terminal to the positive of the other terminal. With a small strip of wire I made the connection.

subwoofer%20023.jpg


Next I put the fiberfill back in the box and wired the sub with the wire that I just penetrated through the box. This is where all the extra wire comes handy. Here you can see I had enough wire to rest the box on the passenger seat and the enough slack to wire the sub.

subwoofer%20027.jpg


Then put the sub in the box and screw in place. I drilled small pilot holes first, rather than just tapping the screw in to avoid cracking the box. Then slide the box into place by tilting the top of the box towards the dash first and then sliding the rest of the box. Notice how well the box fits. I’m convinced it uses every usable inch of space back there. As you can see the foam padding was too long and needed trimming.

subwoofer%20030.jpg


After using a utility knife the padding fit flush.

subwoofer%20032.jpg


Next comes the speaker grill. The grill fits nice and flush and is attached by 4 aluminum brackets provided by SOS.

subwoofer%20037.jpg


Next push back the carpet. Either I didn’t get the box in far enough or the box changed the dimensions of the foot well enough that the carpet didn’t fall back into place cleanly. There was still a lot of slack and buckling in the carpet. I think when I go back to clean up the install,a series of cuts into the carpet will easily fix the problem.

subwoofer%20033.jpg


Finally the floor mats go back in.

subwoofer%20035.jpg


Turn on the stereo and BOOOM! The sub and box sound excellent. It’s nice and boomy but relatively tight and clean. I wouldn’t say it is the tightest bass I’ve ever heard, but it was much boomier than I had expected. I even got it to read +/- 0.02 g's on my g-meter it shook my console that much! :eek: Perhaps its because the NSX has such a small cabin, but the bass was very loud and deep. It’s almost deceiving how much punch it can deliver from such a small enclosure. It was very impressive.

My only two gripes that I could think of was that the speaker grill was made of plastic and not metal as I had hoped. It’s still very strong and I’m not too worried about it but I can be paranoid at times and my biggest fear is that a passenger could accidentally kick through it, not knowing the sub is right at their feet. I might consider putting a metal mesh grill there in the future but I’ll see how the plastic holds up. ***UPDATE*** Upon futher review, I discovered that the subwoofer grill IS made of metal (thanks to Chris of SOS for correcting me). This is good in that it won't snap like a plastic grill will. However, does have some give so it may bend or dent if kicked hard enough. It's not flimsy like aluminum foil, but it's not rigid like a barbeque grill either. I'll keep an eye on it and snap some "later" pictures here after some time with foot traffic.

The other gripe I had was that while the bass sounded good, there was a very slight minor flapping sound when the bass hit at high volume. It’s not distortion because I’m very familiar with how distortion sounds. It was more like a flapping sound rather than the burping sound of distortion. It’s hard to describe, but it wasn’t really a big deal because you can barely hear it and once you have the carpet back up, you can’t really hear it at all. Also, I’m not fully convinced yet that it might even be a problem with the sub itself. Since it was a really fast install, it just needs some tweaking. ***UPDATE*** After some tweaking I really don't hear any flapping sounds. It was probably a result of my poor sealing/seating of the sub in the box.

But don’t let those two things take anything away from the overall performance. This sub/box combo is a real winner. SOS has put out an excellent product It sounds great. It fits great. The quality is top notch. And it comes from a grade A company. It was worth every penny spent and I highly recommend it to anyone looking to upgrade their subwoofer.

I’m giving it my first real test drive along the Vegas strip tonight. I’ll follow up with the results of my ride and let you know how it performs in action.
 
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awesome job, this is my next project.... how much was the box?? looks great nice job!!!h
 
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Much appreciated for the write-up Vega$ - glad you're enjoying it so far!
Make sure you tune it in with appropriate crossovers - actually with the 9833 you can use the built-in sub crossover and use the full band on the amp, or additionally roll it off with your amp low-pass filter set at (or just a little higher than) your head crossover-over (the amp will most likely have a steeper cut-off slope) - make sure it is not set too high if you're only using the amp cut-off. Ensure the door speakers are also crossed over at the same frequency using the head unit &/or amp high-pass so you don't get any wash-out.

If I could make a couple of small suggestions (more for other users going forward) :
1) I actually removed the other blue cable channel that you left in there on the left side and rotated the yellow harness a little further up - this avoided creating that doubled over section.
2) For the hole for the speaker wire - I'd suggest making this on left side of the box rather than the rear - that way the wire won't sandwich between the rear of the box & the footwell, spacing it out a little further (every 1/4" helps!) (you could alternatively make it on the right side, depending on which way your route the speaker wire)
3) Unless you're using a dedicated sub-amp, rated to be 1 ohm stable, then the SOS unit will generally always require to be wired in series for 4 ohm load - for other users, please don't install this at 1 ohm, especially if you are using a bridged amp (like the SOS complete system). You will experience sufficient volume from this, don't worry!
4) The carpet - if you check out this post you will see I cut off my carpet flush with the front of the box - it will tuck slightly under the lip for a neat flush finish - this will remove a lot of the "bulk" from under the top finish mat.


But hey, these are minor details! Great job, Vega$!

Here's an old pic I found of the footwell with the OEM Bose mount tabs popped off and the yellow harness all tucked away (my carpet is completely removed here in this photo)

.
 

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Correct me if I'm wrong, but isn't polyfill used to trick a sub into thinking the box is bigger (volume) when it's not? Bazooka does this effectively and was wondering if this is similar to it.

I guess I could ask the real question....why use polyfill in the first place?
 
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Veleno said:
I guess I could ask the real question....why use polyfill in the first place?
Been accepted practice for years now - does indeed give the effect that would similarly be from as if the box were of bigger volume i.e. lower frequency capability. The polyfill actually dissipates the heat generated by the air movement which makes it more difficult for the cone to work freely. It doesn't make the box bigger (duuuh - obviously!) but gives the net effect of a bigger box where there is less impact from the heating effect.
Excellent article here from Tom Nousaine who explains how it works & the actual gains that can be expected.
Ideal amount of fill for this size box is ~ 1lb.
 
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ryans said:
... I believe those only work on the NA1's as the NA2' have the computer there? I could be wrong but I remember my friend running into that problem.
There is provision to relocate the EPS module to accomodate those equipped cars also. The instructions explain how to do this.
 
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just a couple points....
the slapping or popping sound 99.99999% of the time is a small air leak. the woofer depends on he vaccum pressure inside the sealed box, even THE SMALLEST leak will have huge issues at high volumes. most on the time it is something simple such as a small amount of poly fill under the seal on the woofer when mounted.

I know exactly how much poly chris and SOS has provided but, if you ever take the woofer out again try using about 1/2 the amount as shown in your pics. I think it will go a little deeper and be alittle tighter.

Ployfill is used in ALL enclousers, home, car pro, etc etc as it helps the woofer to not see a standing wave. air moves like water, standing waves cancel each other out. if the air comes off the cones into the back of the box and bounces right back into the woofer cone it is a bad bad thing.

it does trick the woofer into "seeing" a larger area as the air filters thru the fill, taking longer to reach the back of the box, making it seem larger.

****note:too much poly fill is worse than none****

glad you like it, now if we could only get larger subs with a 2.5 or 3 CF box :)


Bazooka used it to stop huge amounts of unwanted port/woofer/motor noise from useing a small woofer tuned very low
 
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D'Ecosse
Did you cut the entire back and sides out of the (passenger floorboard)carpet for the box to fit better or just the bottom part? After looking at the pics there seems to be a gap around the floor mat. Does cutting the carpet out eliminate this gap? If not it seems like the floormat might need to be a little larger. The box looks first class! :biggrin:
 
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nsxot1c said:
awesome job, this is my next project.... how much was the box?? looks great nice job!!!h

You should probably get a direct quote from Chris at SOS but according to his post here it runs $499.00 for the combo, which is what I paid as well.
 
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Thanks so much for all the tips, comments and compliments. It is all very much appreciated.

I just got done with a Las Vegas strip test run and it was great. The sub held up great without any problems. The sub can easily be heard outside the car with the windows down. Let's just say I got about twice as much attention as I normally get, which is saying a lot because the NSX gets so much attention on the strip as it is. By the end of the night my ears were ringing and numb and the last time they felt like that was when I had my Honda Accord pushing 1,000 watts and two 12” subs.

I had so much fun doing this one, and due to all of the positive feedback, I plan on doing another review and write up on Stacy's side skirts when I get them in a few weeks.
 
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D'Ecosse said:
Much appreciated for the write-up Vega$ - glad you're enjoying it so far!
Make sure you tune it in with appropriate crossovers - actually with the 9833 you can use the built-in sub crossover and use the full band on the amp, or additionally roll it off with your amp low-pass filter set at (or just a little higher than) your head crossover-over (the amp will most likely have a steeper cut-off slope) - make sure it is not set too high if you're only using the amp cut-off. Ensure the door speakers are also crossed over at the same frequency using the head unit &/or amp high-pass so you don't get any wash-out.

If I could make a couple of small suggestions (more for other users going forward) :
1) I actually removed the other blue cable channel that you left in there on the left side and rotated the yellow harness a little further up - this avoided creating that doubled over section.
2) For the hole for the speaker wire - I'd suggest making this on left side of the box rather than the rear - that way the wire won't sandwich between the rear of the box & the footwell, spacing it out a little further (every 1/4" helps!) (you could alternatively make it on the right side, depending on which way your route the speaker wire)
3) Unless you're using a dedicated sub-amp, rated to be 1 ohm stable, then the SOS unit will generally always require to be wired in series for 4 ohm load - for other users, please don't install this at 1 ohm, especially if you are using a bridged amp (like the SOS complete system). You will experience sufficient volume from this, don't worry!
4) The carpet - if you check out this post you will see I cut off my carpet flush with the front of the box - it will tuck slightly under the lip for a neat flush finish - this will remove a lot of the "bulk" from under the top finish mat.


But hey, these are minor details! Great job, Vega$!

Here's an old pic I found of the footwell with the OEM Bose mount tabs popped off and the yellow harness all tucked away (my carpet is completely removed here in this photo)

.

Once again, the stereo king represents to put me in check. :biggrin: Everything you say up there is spot on. Hopefully when people do the install, they will read far enough down the post to your reply because I couldn't agree more with your points.

Thanks so much compliments. Coming from you, that means a lot! :smile:
 
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01blacks4 said:
just a couple points....
the slapping or popping sound 99.99999% of the time is a small air leak. the woofer depends on he vaccum pressure inside the sealed box, even THE SMALLEST leak will have huge issues at high volumes. most on the time it is something simple such as a small amount of poly fill under the seal on the woofer when mounted.

I know exactly how much poly chris and SOS has provided but, if you ever take the woofer out again try using about 1/2 the amount as shown in your pics. I think it will go a little deeper and be alittle tighter.

Ployfill is used in ALL enclousers, home, car pro, etc etc as it helps the woofer to not see a standing wave. air moves like water, standing waves cancel each other out. if the air comes off the cones into the back of the box and bounces right back into the woofer cone it is a bad bad thing.

it does trick the woofer into "seeing" a larger area as the air filters thru the fill, taking longer to reach the back of the box, making it seem larger.

****note:too much poly fill is worse than none****

glad you like it, now if we could only get larger subs with a 2.5 or 3 CF box :)


Bazooka used it to stop huge amounts of unwanted port/woofer/motor noise from useing a small woofer tuned very low

I think you're probably right. I 'm thinking I probably didn't do the best job of sealing the sub. It probably wasn't the fiberfill because SOS really didn't put that much in the box. I know in the pictures it looks like there is a lot but once you stuff it in all the nooks and crannys, there leaves a lot for the actual sub. But I think when I screwed the sub into the box, I bet I didn't do the best job of seating it. The good news is once I had everything back in place I didn't hear any flapping at all and everything sounded great. Thanks for the heads up though!
 
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mackash said:
D'Ecosse
Did you cut the entire back and sides out of the (passenger floorboard)carpet for the box to fit better or just the bottom part? After looking at the pics there seems to be a gap around the floor mat. Does cutting the carpet out eliminate this gap? If not it seems like the floormat might need to be a little larger. The box looks first class! :biggrin:


Look at posts 20 to 28 in this thread where D'Ecosse describes the floor mat fit issues:

http://www.nsxprime.com/forums/showthread.php?s=&threadid=31118

Please check with Chris at Science of Speed for a possible group buy (minimum 6 orders of a set) on my customized floor mats. HTH.
 
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Hrant said:
Look at posts 20 to 28 in this thread where D'Ecosse describes the floor mat fit issues:

http://www.nsxprime.com/forums/showthread.php?s=&threadid=31118

Please check with Chris at Science of Speed for a possible group buy (minimum 6 orders of a set) on my customized floor mats. HTH.

Having a full set of your Ivory/Black floor mats I can attest to these as well. These floor mats are top notch. The fit, quality and cut are all excellent and I actually prefer them over the OEM mats. I highly recommend them! :smile:
 
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Vega$ NSX said:
But I think when I screwed the sub into the box, I bet I didn't do the best job of seating it....
Especially when you pre-drill (which is a MUST not a nice-to! - Good job on that one, Vega$!) it's easy to leave a burr standing high, so clean it off with a countersink or just scrape with a blade. Good idea to put a seal of silicone around the flange too between the speaker & the mounting ring. (it's not like you'll be taking the speaker in & out of the box frequently!)


mackash said:
Did you cut the entire back and sides out of the (passenger floorboard)carpet for the box to fit better or just the bottom part? After looking at the pics there seems to be a gap around the floor mat. Does cutting the carpet out eliminate this gap? If not it seems like the floormat might need to be a little larger.
I actually slit the carpet as it transitions from the floor to the side, then cut off the floor part so it just tucks under the box at the bottom (at the corners it is not cut straight across, but left a little "tail" that fits under the corners to ensure no paint is showing. (See pic below)

I'm kinda anal about how the mats fit, it has to be perfect for me. So I actually made a paper pattern for a completely new mat which Hrant custom made for me - I bought a complete set of course with stock drivers side & custom passenger side. Of course you can have a wide choice of colours & trims as you choose at the same time! No need to go with the stock Acura colours although I selected the Zanardi look same as I had previously. I also like the foam pad on the back of the Hrant mats as opposed to rubber of the OEM mats, particularly over the speaker.

Check them out in this thread

Another option some might like, would be to customize the fascia of the box - there are many different covers you can put on the face from all kinds of materials - sky's the limit really on what you can come up with by either making yourself or there are a ton of ready made or custom choices out there if you google for them.
http://www.autoacoustics.com/grillehome.htm - these guys can cut any logo (NSX maybe?) you want in a perspex cover in a variety of colours too.
Nice shot of DocDan's laser cut grille here

Then if you want to leave it exposed to show off your sub you could have Hrant make a custom mat that just stops at the base (instead of going up over the face) with it bound in serge all the way around as per a complete mat.

.
 

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Hrant said:
...Please check with Chris at Science of Speed for a possible group buy (minimum 6 orders of a set) on my customized floor mats. HTH.
Did you save my pattern Hrant, or would like a new one traced from mine?
pain.gif
 

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I have a stupid question:

NSX comes with a stock sub on the passenger footwell? :confused:
 
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D'Ecosse said:
Did you save my pattern Hrant, or would like a new one traced from mine?
pain.gif


Aha, we are back visiting the commission or royalties heh :tongue: And don't you worry Ken, with the type of favorable posts you keep tossing my way, I would be dumb not to take care of your marketing freebies ..... :biggrin: :wink:

I will check with the shop if they kept it or not. And I am presuming SoS's set up would lend to the same identical floormat template that you designed; if so, this should simplify life to all.

Sorry for the sideshow, back to the regular progromming.
 
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How much fiber-fill should be used in a box (The Golden Ears-Dali one) that I think is a little smaller internally then the SOS box? I'm using a DynAudio MW180 sub (9.7") if it makes a difference. I'm thinking it should be just under a pound.
 
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it should LOOSLY fill 1/3 of the box it never should go by weight.....it will prolly really really really help the Dyn sub


did i mention that it will probably help that dyn sub you have to stuff the box?

just a FWIW home insulation (yeah the pink stuff) is actually prefered to polyfill.
 
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vtec888 said:
I have a stupid question:

NSX comes with a stock sub on the passenger footwell? :confused:
No it doesn't - there is a speaker assembly in the passenger footwell but although it appears to be colloquially called a "sub" it is not.
 
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Hrant said:
... I will check with the shop if they kept it or not. And I am presuming SoS's set up would lend to the same identical floormat template that you designed; if so, this should simplify life to all.....
All joking aside Hrant, be happy to copy it - I'll get my reward in heaven no doubt! ;)
However it might be safer to create a new pattern for the new box - although very similar, the mould for the SOS unit may be slightly different from mine as they were both free-formed independently (of course all the SOS units will now be identical going forward).
I can get you a pattern in about a week to 10 days from an install I'll be doing however. (I'll also try my mat once the install is complete in the "new" car to see if they are the same)
 
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mandrewz said:
... (The Golden Ears-Dali one) that I think is a little smaller internally then the SOS box? ...
No disrespect but I think it's a lot smaller than you think - maybe half the SOS box volume from my estimation of the pictures.
That Dyn is a fine speaker but needs minimum of 0.75 cu ft to work in - even the polyfill is not going to get you there with that box I'm afraid.
(recommended sealed box for the MW 180 is 21.2 - 56.6 litres or 0.75 - 2.0 cu ft)
That thing is flat all the way to 2 kHz so it is probably giving extremely good low-mid range response, but is probably missing out on the capability for the real low sub's in that enclosure.
 
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