FR-S / BRZ / GT 86 - Fiberglass Subwoofer Enclosure Prototyping by Integrity Concepts

[Integrity Concepts]

Soundman98,

Thank you for doing such a complete review and for your additional attention to the minute details. I can't wait to hear your thoughts once you get it all installed and tuned!

I wanted to comment briefly on your small points of issue, because while you do not fault us directly, I do want others reading to understand the degree at which these things actually effect the average listener, and our thoughts behind each choice we've made with the enclosure design (along these lines).

I will start by saying that in every aspect of the design of these enclosures we have heavily weighed in each material and process and chosen the best options for what we believe to be a consumer product of the highest quality while still maintaining a reasonable price. We also believe you feel the same, after all you have chosen our enclosure for your high end install.

As you have pointed out in your review, even a great design can be further improved by the end user if the extra effort is found to be beneficial to them. This is to say that the high level of your install and the modifications you have chosen to carry out on the enclosure hold great merit, but they are by no means necessary to achieve great sound from our enclosure, and so we don't want others reading to feel like they need to carry out the same mods.

1. Your first issue being the terminals included on the enclosure. We chose to go with a bolt through gold plated binding post that allows quick disconnect of the speaker wires on both ends through turning of the knurled heads, for an extremely solid and reliable connection with as few breaks in the line as possible. As you have noted our supplied binding posts have small banana plug pin holes that carry through the body. After inserting the sub wire into both ends of the post and fully clamping them down the hole is sufficiently sealed and there is virtually no air movement through it. We have ran air pressure tests at 10 PSI to confirm this even though a typical sub in a sealed enclosure produces less than 1 PSI in the 140 DB range. The other binding post styles available have a male spade on the inside of the binding post which accepts a female crimp connector, and we have found that this type of crimp connection has the potential to vibrate loose, does not supply as much surface connection verses a direct input of the wire into the binding post, and actually makes one more break in the overall signal line unless soldered on. After weighing these pros and cons of each style we landed on using the terminals we've supplied with the enclosure. The choice to change them out is not good or bad but more or less one of personal preference as it does allow the use of a larger speaker wire, but I would recommend a soldered connection is made on the crimp connector.

2. The second issue being the carpet that extends over the subwoofer mating surface to the cutout of the enclosure. As you mentioned this seems to be industry standard. I cannot tell you for certain why other manufactures do this but I can tell you why we have chosen it. First of all, subwoofers come in many different overall diameters. This means if we trimmed back the carpet and did not carry it at least part way across this surface, a smaller sub that does not extend to the edges of the opening may show the unfinished surface beneath, and when one of our optional press fit grills is not being used to cover the opening this can ruin the look and finish of the final product. So the carpet is carried all the way to the edge in part to present a finished product from the second it is taken from the shipping box to the final appearance in the vehicle. The carpet sandwiched between the subwoofer and the mating surface when properly compressed (by fully screwing down the woofer) actually provides a very sufficient seal, though not as good as a foam or strip caulk seal, it still wont leak enough air to make an audible sound or a difference in the subs performance. Though we all strive to achieve a well sealed enclosure it is interesting to note that a completely "perfectly" sealed enclosure has actually been found to be a bad thing. Studies have found that a small pinhole equalizes the static air pressures inside and outside of the enclosure. In other words a perfectly sealed enclosure can cause the sub to be affected by various pressures inside and outside the enclosure like atmospheric pressure or the more common pressure from heat build up within the enclosure. Studies have shown this happening in as little as 30 minutes of playing the sub in a perfectly sealed enclosure, the motor structure generates heat and the heat builds pressure that in turn causes the cone and surround to bulge, and this does negatively affect performance. However a small leak allows the subwoofer to return to its intended resting position. Now I am talking a small hole or leak when I say this, but leaks don't kill performance, they can just create noise. If a leak is small enough to not be audible, it isn't killing the performance as its effects are entirely inaudible. A larger hole or leak is obviously going to affect not only the audible sound but the dampening of the cone, and that is not what we are talking about here. So does the extra work to trim the carpet back and put down a sealant make a difference? It is not going to hurt, but with the carpet in place if there is no audible noise and it is not a big enough leak to affect the dampening of the cone then it is not negatively affecting performance and may even be a good leak source for equalizing the pressures. So while we are wanting to supply a finished looking product that will work with various sub diameters while still supplying a quick and sufficient seal, we have chosen to carry the carpet to the edge.

Lastly the polyfil dampening material being replaced with fiberglass insulation. There have been multiple sources that show that Fiberglass insulation is better suited for the task of dampening the lower tones of a subwoofer, with the polyfil not far behind and actually a better choice than the insulation for small enclosure mid range tasks. The choice to use polyfil over fiberglass insulation in our enclosures was solely an issue of not wanting to send out a potentially health hazardous material to our customers.

Again I am glad to see Soundman98 taking the time to make sure he gets his system right, and the way he wants it the first time. All too often it is the opposite, with people cutting corners, who could care less about how it sounds. Keep up the good work.

.

[chanomatik]

Can't wait for my enclosure. Will be exciting!

[chanomatik]

Edit! Edit! My bad! Running off very little sleep after a busy weekend and a busy day today!

[ZOMFGAARON]

Originally Posted by Integrity Concepts

Ok, so now you leaked it.

Yes, we have been working on a shallow mount enclosure option for a Passenger side 10". It will be specifically for those with slim / shallow mount subs, and thus have a smaller volume and take up a smaller footprint in the trunk.

Subbed for shallow mount enclosure.

[chanomatik]

*shame*

[Integrity Concepts]

Too funny, LOL ! Nice try being quick on the edit, but now it's really leaked.

[chanomatik]

Well I guess it's just hype being built up until something is shown! And good to know others are standing in line too. This is why I'm not allowed on the Internet with this much sleep deprivation! Bad-like things happen!

Still can't wait. This is the only product for me.

[OICU812]

YAY I got my two 8" lh&rh enclosures coming, pretty stoaked!!

[soundman98]

worked on the car some today and wanted to update this thread-- you CAN install the sub on top of the subaru floor mat, it just needs some trimming.

[chanomatik]

Originally Posted by soundman98

worked on the car some today and wanted to update this thread-- you CAN install the sub on top of the subaru floor mat, it just needs some trimming.

Okay, now THAT little bit of trimming I can totally live with. Thank you!

[soundman98]

yeah, i think it could be further trimmed and re-formed with a heatgun to conform around the front edge of the sub, so spilled liquids don't get under it, but this is plenty for what i need the mat for.

[Integrity Concepts]

Here is another install with the factory Subaru trunk tray in which the customer trimmed down the tray wall where the enclosure sits. I'm not sure if this improves the fit over trimming just the top edge as previously pictured, but he had no issues achieving a perfect fit using this method.

[OICU812]

Got my drivers and passengers 8" IC enclosures in. Both in look, overall construction are great. Leak tested good and fitment is spot on. HUGE props to Dan @Integrity Concepts for all his help throughout the process. Very pleased with the results! I removed a tad bit of poly fill estimating air space around .50-.55 cubic feet. I installed 2 Focul P21 V2s.

Here are some pics

[Integrity Concepts]

Originally Posted by Top-Secret

are you guys going to offer this in a 12''? as im sitting with 2 brand new type R 12s and would like a box similar to this. instead of having something custom made

While we do not have plans to produce a 12" Integrity Enclosure model for the FR-S / BRZ / GT 86, due mostly to space constraints, there has been quite a few individuals that have asked this same question, and your particular 12" woofer choice got us thinking about the possibility of modifying one of our 10" enclosures to do the job.

The Alpine Type R 12" subwoofer (SWR12D2/D4) is recommended by Alpine to have a net sealed enclosure volume range of .55 cu ft - 1.0 cu ft, which is quite small as far as 12" subwoofers go. Our 10" enclosure volume of .75 cu ft falls within this range, so the question is: Can our 10" enclosures be modified to physically house it? Below we have provided a pic in which we mapped out where the Type R 12" overall diameter and mounting screw diameter would fall. With the woofer bumped out to this position on the face of the enclosure the woofer depth and magnet diameter are no longer a problem to physically fit within the enclosure.



As shown in the above pic the mounting screw holes fall directly on the ridge of the opening and this in and of itself poses the biggest problem. The area inside the opening would need to be built up flush with MDF molded in to have the proper cutout diameter and give the subwoofer a good surface to seal and mount to. Also the area outside the ridge should be backed with MDF for the best mounting screw grab regardless of the direction the screw is driven.

With this bumped ring modification to the enclosure we would gain a bit more volume within the enclosure bringing it up to around the "optimum" internal airspace of .85 cu ft recommended by Alpine for this woofer. Plus Plus! The only drawbacks to this modification would be the slight added weight, the slightest outside edge of the woofer that might not lay perfectly flat all the way around but probably appear so with the carpet filling the void, and the fact that it would obviously render the enclosure incompatible with our press fit grill (though the Alpine woofer in question has its own optional grill, so that's an easy solution).

In the end the modification would appear similar to this 10" enclosure pictured below that has been modified to house an oversized 10" subwoofer, with the only difference in appearance being the mounting rings bumped all the way up to the top ridge and a slightly larger cutout diameter.



If you or anyone else is truly interested in this modification to fit a 12" subwoofer into our 10" enclosure, please let us know and we can work out the details with you and provide a quote for performing it.