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

[Integrity Concepts]

Originally Posted by labskaus

I would suggest a better fixing of the volume in addition to the fixing point on the top

See, the three holes near the wheel housing?


I put a metal bar behind it


So I can put a screw from the inside of the woofer volume to fix it


finished


Will work on both sides

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Your system looks nice, good job! Thanks for the constructive input as well. I'll explain why we chose to mount our enclosures the way we did below.

Our goal with the mounting on all of our enclosures is to create a tool-less quick release system that requires no permanent modification to the vehicle. If we had utilized the factory holes in the sheet metal behind the enclosure, and more specifically the one you have used behind the trunk liner, one would have to cut a hole in their trunk liner to perform the install and may need a professional shop to aid in the installation. They would also have to remove their subwoofer from the enclosure to access the mounting bolt, in the event they would like to remove it for track days or to access their spare. Then there is always the chance that the sealed enclosure could leak air through the hole that is drilled for the bolt unless it is properly sealed or tightened enough to be seated well on a set of rubber washers. All of this is great when the customer is into DIY, it is a custom install, or our enclosure is to be installed by a professional shop, but we wanted to eliminate all need for that and the chance for any errors.

Because our enclosure is a perfect fit and the back is an exact copy of the contoured corner of the trunk, our enclosure can only move one direction, and our tab system prevents that lateral movement, yet allows the enclosure and woofer to be removed from the vehicle in under 30 seconds, and does not require permanent modification to the vehicle or professional installation.

As far as your comment about better securing the enclosure at the larger volume of the part as apposed to just the top: We have included a small optional strip of back to back Dual Lock with each enclosure we ship, that can be placed on the underside lip of the enclosure below the woofer opening. This strip mates the carpeted surface on the underside front edge of the enclosure with the factory carpeted trunk floor, and provides some extra friction for even more resistance to lateral movement. We supply it in the package as only an option, because after repeated removal it can wear on the threads of your factory carpet, and we would rather leave that choice up to the customer. Besides we have found that our tab system (when installed properly) is more than enough hold for most customers, and so the strip should really only be needed for extra spirited driving!

Our 8" enclosures are a completely different mounting system that utilizes a bracket to a factory trunk liner clip hole outside of the enclosure, with a bolt and thumb screw setup. Still a quick tool-less removal with no permanent modification to the vehicle.

[Integrity Concepts]

Originally Posted by labskaus

Sure, it is not quick removable, but you will never have any noise because of rumbling woofer volumes.

It is a nice piece of work.

I can assure you that there is definitely no more noise from "rumbling woofer volumes" with our mounting system than those that are bolted through. In fact there may even be less unwanted noise with our mounting system, due to the fact that we are not attached to the area behind the rear quarter panel of the vehicle which is the most prone to vibration and transfer of unwanted noise. We have also gone the extra mile and coated the back of each enclosure with a thick layer of Cascade Audio Engineering VBX-1 liquid sound dampening compound to really eliminate any unwanted sounds a fiberglass enclosure may produce, so that the woofer can do the talking.

Here is a video of a woofer being pushed in our 10" passenger side enclosure. Sounds great with no unwanted rattles, granted you'll have to take into account that the recording and playback devices for this video are probably not adequate for reproducing the low tones coming from this sub and enclosure combo.

Dayton HF 10 playing in our 10" Passenger side enclosure

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[labskaus]

Originally Posted by Integrity Concepts

Cascade Audio Engineering VBX-1 liquid sound dampening

imho
Xtra layer of glasfiber should have the same effect (stabilizing) or some black sprayed color (minimize dust)
both cheaper

[Integrity Concepts]

Originally Posted by labskaus

imho
Xtra layer of glasfiber should have the same effect (stabilizing) or some black sprayed color (minimize dust)
both cheaper

Some may believe that VB-1X does not serve any purpose, but the results have been tested and proven by CAE.

"VB-1X is an air curing, liquid vibration damping compound. Its combination of silica-mica, ceramics and an advanced chemical binder greatly reduces structural resonance by converting vibration into “viscous” friction or low level heat. VB-1X will also increase speaker output by .5 to 1 db when applied onto the inside of a speaker enclosure."

An extra layer of fiberglass instead of VB-1X would not do all of the above. We both add the extra layer of fiberglass as you recommend (our enclosures are 5/16" - 3/8" thick where others are at or below 1/4") and then we still coat our enclosures with the VB-1X.

[labskaus]

Sorry to be impolite, but this is no fairy dust.

I know this kind of stuff and I know how to use it. It has some effect to make a surface more rough and reduce reflections (midsub and midrange).

Like I said, the walls must be so thick or strengthend, that they will not swing and everything is fine. For a clear conscience add some foam behind the subwoofer to diffuse frequency waves. Or to increase the effective volume add some accustic whool.

Another option is to add sand or metall dusts (iron, brass) to the glasfiber to give it more weight (only the inner layers). Nice effect, it makes the surface more rough.

Gain of 0.5 to 1db? Wow ... +10db means it is double loud then before. people hardly regonize a difference of 3db.

[labskaus]

Originally Posted by FreshFRS

while 3 db might not be noticeable to the human ear, adding 1 db of output is roughly the same as adding 25% more power to the given speaker. 3db of gain would mean effectively doubling your amp's power and 10db would be 10x the power. This plays into your amps efficiency, if you can run minimal to zero gain on your amp (you should try to do this anyway imo) but still put out the same volume/spl as before (with some gain), why not? just less power the amp has to use, and the cooler it will run.

Have you read your text?

Gain is to adjust the outputlevel of the radio/processor (2V to 10V) to the input level of the amplifier. It is not to adjust the amplifier performance / output(!!!!)

And to the rest, you are not gaining 1db, you are not loosing 1db. So if your woofervolume is build right, with stuff do nothing.

Originally Posted by FreshFRS

sidenote: i haven't used this stuff before but if it works (as advertised) i can see the potential benefits of it.

Used it first, then judge about the potential

Build a really stabil woofer volume. and do your measure with and without. You will see no difference(!).

[Integrity Concepts]

Originally Posted by labskaus

Sorry to be impolite, but this is no fairy dust.

I know this kind of stuff and I know how to use it. It has some effect to make a surface more rough and reduce reflections (midsub and midrange).

Like I said, the walls must be so thick or strengthend, that they will not swing and everything is fine. For a clear conscience add some foam behind the subwoofer to diffuse frequency waves. Or to increase the effective volume add some accustic whool.

Another option is to add sand or metall dusts (iron, brass) to the glasfiber to give it more weight (only the inner layers). Nice effect, it makes the surface more rough.

Gain of 0.5 to 1db? Wow ... +10db means it is double loud then before. people hardly regonize a difference of 3db.

Your not being impolite, your just voicing your opinion in an attempt to help us better improve our product. We appreciate that you are constructively supplying us with alternative options. That being said, please know that we also know this kind of stuff, and are by no means aimlessly throwing rather expensive materials at our enclosures. Let me unpack this for you...

As stated before, we build our fiberglass enclosures thicker than most on the market, and we do this while maintaining techniques that keep the resin to mat ratio lower and the overall composite more compact for a stronger and lighter part. We even designed the enclosures with ribs in the flat areas to increase rigidity. We have taken many measures to ensure that the enclosure itself will not flex in the slightest when placed under load. But even then, the material properties of fiberglass, no matter how thick or rigid, pose an inherently higher resonant tendency than say MDF. This resonance is not necessarily bad, just different / usually higher and less absorbed by the more dense material. Fiberglass is also less consistent than MDF which is why a fiberglass enclosure of the same volume but different shape, design, and even layup technique can have a greatly different sound. Really we are talking about many factors here.

So in the case of whether or not VB-1X is a suitable aid for dampening vibration and increasing output:

We are well aware of its physical properties and limitations, and do not pretend to think it is a fix all fairy dust nor rely on it to take care of the same kind of vibrations or noise I feel you may be talking about. While your opinion is valuable we choose to side with the manufacturer on this one. Cascade Audio Engineering is just that, audio engineers, that have been reputably around a long time, they know this stuff as well, and back their products with proven results from testing. A .5 - 1 db increase, as I quoted in my last post, was just a portion of one of their most comprehensive statements on the product and is actually a conservative result. Their tests frequently log 1 - 1.5 db increases with some measurements up to a 3 db increase. This change in increase is based on a number of factors but mostly due to the material it is being applied on and how it is being applied. They state that it effectively dampens vibrations between 10Hz and 40KHz, but that it becomes more effective in dampening frequencies above 200Hz. Being that fiberglass has a higher resonant frequency and VB-1X is more effective at higher frequencies, it shows why VB-1X could have more of an impact on dampening vibrations in fiberglass than MDF or other speaker enclosure materials. CAE have also stated that the material becomes way more effective after fully curing, which can take up to 30 days under proper conditions.

In my opinion, these are all things I think one needs to take into account before chalking it up to "fairy dust". Have you used this exact VB-1X product? - As there are many similar products out there that claim to do the job but really have a completely different material properties makeup from VB-1X. Have you used this exact product on a fiberglass enclosure or substrate? If yes to the ladder, have you properly applied it based on the manufactures suggested techniques to increase the dimpling effect and thickness on the surface? Lastly, did you wait at least 30 days for a full cure, before testing it and throwing in the towel?

So lets say it does all that the manufacturer says it does, dampens higher frequencies of vibration and can produce tested results with an increase of up to 3 db. Is it of value for us to spray it on our enclosures? I guess it depends on who you are taking to. Another member of this forum apparently chimed in to say that it is, but was shot down for his terminology, and ended up deleting his post. I am sure we could open a big debate as to how much of a db increase is worth it, but that should probably be for another thread, and really any db increase is just an added plus for us and the customer as the main reason we have chosen to use this VB-1X product is for its vibration dampening properties and because it makes for a nice matte black finish inside and out.

While some of this subjects terminology may be different in Germany and ultimately be misunderstood in translation, it is important to note that when talking about db's there are several measurements to go by. The measurement you were referring to about doubling at 10 db's is for "perception" of sound which is all based on pshycoacoustics, the listening ear and otherwise known as the loudness gain factor. The measurement that FreshFRS was referring to for doubling at 3 db's is for the "cause" which is based on energy or power quantity and is also known as power gain factor. When working with power, a simple rule of thumb is that 3 db means double (twice) the factor, and 10 db means 10-fold! The one that has not been stated yet is a doubling at about 6 db's which is the "effect" and is based on field quantity of sound pressure and is also known as the voltage gain factor. So which measurement is Cascade audio Engineering referring to in their test results? Well I can say they are not just perceiving the results at 10 db's, and I am pretty sure, though not certain, they are not taking the measurements based on power quantity at 3 db's, though they very well could be. Really the proper and probably easiest way to measure it is by SPL and this is doubled at 6 db's in which 20 db's is 10 fold.

So I guess the question is, is it worth it to potentially increase your output to 150% - 200% of its original (depending on CAE's form of measurement when testing) just by spraying this stuff on? We think so. Plus it dampens possible higher vibrations of fiberglass and is a nice refined finish inside and out to boot.

Again this is just us unpacking for you why we use the stuff and not meant to be a knock to your opinion. We do also include with every enclosure the acoustical wool you and most subwoofer manufacturers recommend. We are also testing the benefits of various materials sandwiched in the inner layers of our composite layup, but they have mostly been in the form of sheet material aluminum, foam, balsa, and honeycomb, not metallic sands or dusts, so we will have to look into that if the benefits outweigh the weight as one of our high priorities is to maintain a lighter finished product.

Dan - Integrity Concepts

[ean611]

@ Dan @ Integrity Concepts. Great info on your construction method.

Can't wait to see pre-orders ship. My HAT I8sw is getting lonely sitting in a cardboard box.

[Integrity Concepts]

Originally Posted by ean611

@ Dan @ Integrity Concepts. Great info on your construction method.

Can't wait to see pre-orders ship. My HAT I8sw is getting lonely sitting in a cardboard box.

Thanks. From time to time we like to give involved write ups as to our methods and material choices. I guess I should get back out to the shop now, and physically get some more work done!

[labskaus]

Thanks Dan for you long posting

But I think, we have some missunderstanding.

I still think you have done a great job on the enclosure, but imho the VB-1x is not working the way you are explaining. It is for midsub and midrange enclosures and will work here. So it is fairy dust - it is expensive and will not have a noticable effect.

But since you can prove an increase of "potentially 150-200%" on the output - okay. Oh, sorry, "depending on CAE's form of measurement when testing" you can prove the potentially increase.

I do not know, how much VB-1X you put into your enclosure, but ...
"When used at equal thickness, VB-1X provides twice the damping qualities of asphalt damping materials!" (http://www.parts-express.com/pe/show...number=268-256)
... forget about it. Color the enclosure inside (just to prevent the fibreglas from dusting) and you still have a fantastic enclosure for a resonable price.

[obriennathaniel]

My comp R8's are getting pretty lonely

[zooki]

Almost 2 weeks since the last update. Starting to wonder which will come first, my 8" box, the Nameless header, or Ragnarok....

[Integrity Concepts]

Originally Posted by obriennathaniel

My comp R8's are getting pretty lonely

Not for long, the first of your 2 enclosures is on its way and it looks like it is in Utah now. A 10" Passenger side enclosure modified to fit the Comp R8!










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[Integrity Concepts]

Originally Posted by zooki

Almost 2 weeks since the last update. Starting to wonder which will come first, my 8" box, the Nameless header, or Ragnarok....

Originally Posted by Integrity Concepts

This week, as stated in my last update, I am back in the shop and working on the molds adding the last few layers of roving and adding the external bracing. The molds will rest in a warm place next week for post mold curing, and then we will pull them apart, wet sand, polish, and wax the molds the following week in preparation for pulling the first pre order production parts!

We are sticking to the schedule for the molds that we outlined in our last couple updates, the last one posted on the 9th is quoted above. The molds were just trimmed up yesterday and we hope to open them up tomorrow, and begin wet sanding and polishing each of them to a high gloss class "A" finish. Then they will each receive 10 coats of mold release wax spread over a couple days.

This molding process in itself has all gone fairly good now that the new space is fully operational... Except heat, the much bigger space is much harder to heat up to our necessary curing temps, and with fall in full motion here in the pacific NW, we need to address this quickly!

On another more personal note: We have also had a rough go around here personally (again), as my elderly Mother, who is living with us and under our care, went into the emergency room early last week and almost died of advanced stage pneumonia. After more than a week of extensive treatment and evaluation at the hospital, she might be released to come home tomorrow! It has been determined that she has a rare lung disease (from unknown causes) that is nearing the end stages and this has made her more susceptible to catching pneumonia in general, but that this more advanced and chronic pneumonia is really based on her aspirating on her food and drink, due to her memory loss and forgetting things like how to properly swallow or clear her throat. Needless to say, I was at her side in the hospital for several whole days last week, and every hour outside of work this week. It appears she is going to recover from this bought slowly over the next 3 weeks, but the doctor says that the next time around will more than likely end her life, and this could really happen at anytime.

All of this has me wondering when things are going to let up a bit in my life and really get back to normal around here. Life is a precious thing and we rarely know when that last day will come for any of us, so while I can promise to work normal hours to get these enclosures built and out to everyone, I cannot dedicate any of my extra time at this time (as I usually would), nor promise that if my Mom passes away that I will have anytime at all for at least the week after.


On a brighter note: We are all caught up on our Passenger side 10" orders and now have them in stock and shipping! We have also completed some interesting modification requests on these over the last few weeks, including the one modified to house an 8" sub from our last post. Here are a few more:

Front coated in a high build primer for a customer who wanted it custom painted by his local shop to match the custom paint on his car. We wet sanded it out to 800 grit and then taped it off and sprayed the sound deadening on the back. Now all that is needed is to mask it on the line and shoot the color!







Below is one that we bumped the mounting surface up 1.5". This was for a woofer with an overall diameter larger than 10.75" that was too large to fit down into the recessed woofer opening. This is also great for anyone with woofers deeper than 7" or with magnets larger than 6.5" in diameter! The woofer still recesses a bit into the area where our grill would normally press into, so it maintains that clean custom look, but has an overall diameter of 11.5". Unfortunately this modification makes the enclosure incompatible with our press fit grill options for obvious reasons.



We are going to keep this stuff coming, with pics of our airspace reduction modification as soon as I get some good ones (its hard to take a picture inside the enclosure). Also pics of more finish options like film wrap, OEM paint, and carbon fiber as they are all on order with our other models!

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