There's no such thing as "stuff made for car audio". It's simply bitumen (basically thick tar) on a foil backing. The only variables here are the tack of the bitumen and the thickness.

I used to wholesale the stuff - the manufacturers marketed them as "foil bitumen membranes" that were useful for roofing, weather sealing, and sound dampening. And they did offer services to print your logo across the rolls, and various textures embossed in the foil, etc. Dynamat is just one of many companies buying the stuff and rebranding it.

Some will have the wrong tack or flexibility for car audio, if you're nervous about pulling a Home Depot, look for an "off brand" car audio material that has good reviews. Odds are it comes off the same factory line as Dynamat.

 

Yeah, I'm absolutely aware of this. And every mfr seems to have a basic-grade asphalt/bitumen sheet, some with or without the aluminum backing. However, there are other materials available as well, such as vinyl sheets and butylene rubber-based sheets, again with or without the aluminum. Non-bitumen sheets tend to have less odor. And the actual damping performance will differ across manufacturer and product lines. Acoustic Loss Factor, an objective measurement of vibration damping performance, also may differ quite a bit across different frequencies and temps.

I would not recommend bitumen-based sheets, unless cost is a big factor (and labor/time is not), and you don't mind the odor. There are better performing materials that weigh less, and their formulations differ across manufacturers. Adhesive is extremely important in car audio - which is why I would recommend sticking with "marketed for car audio" (happy?) products, which take this into consideration. I've repurposed other damping materials, and they're either a pain to apply, they don't stick well, or they peel off over time - but hey, they were also cheaper.

 

Which dampening products do you suggest? I always spent a lot of time talking people out of buying dynamat, which was nothing other than a high-tack bitumen on foil, and sold them either the exact same thing without branding, or 3M 2552 viscoelastic foil (big bucks). Bitumen is a loosely controlled material, it varies *widely* in odor, tackiness, density, and so forth. I've never actually seen a petroleum based foil that had any adhesive at all, just bitumen of varying tackiness.

 

We carry Dynamat here at the store. Even the extreme or ultra lite you still need to clean the surface. (We use windex works well) and we still heat the material before we apply it.

Accurate is a good alternative. A little creeper and scosche is a good company. Personally I prefer it and use it in my personal cars.

Best sound deading material is wood. 3/4 inch MDF or 13 ply 5/8 birch ring. Main thing dynamat is seals up the door to create a baffle and kills resonating frequencies. Now there's ton of low grade stuff out there but depends on the quality and density. It makes a huge difference. Higher end cars use a version that looks like the original Dynamat or Brown Bread in OEM cars like MBZ AMG to quiet the cabin. Stuff work but you don't need to go crazy with it. We normally can use 36 sq feet bulk pack to do a trunk and all 4 doors. So if you use is wisely. The investment.
around 200.00. (Dynamat or accuamat).


Shipping on the other hands a nightmare. It's like 45lbs I think. Lol.

 

*cheeper

 

I have 50 sets of xover at my shop trust me for basic upgrades no xover needed. I done over 1800 Porsche installs over 16 years All you need is a 3.8 ohm cap on the tweeter. That's it. And drop them In.

Try it. And never out a crossover in a door. We when we use xover mount them under the seat away form the fire wall. Xover like to create an engine wine in the audio system

If your getting Alt wind move the x overs.

 

Hi shane glad you could share your vast experience on sound system upgrade. What do you think of speaker upgrades using oem pcm and bose amp? Are the bose outputs already managed and just wiring them straight into speakers negates need for any crossover? Focal has integration speakers what do you think of them? Specifically the 8" component system. Your opinion and expertise will surely be appreciated here.

 

As far as we know factory audio systems are designed not to blow speaker. When you scope the Bose amp it does have factory preset crossovers. We normally use 3.8 omh cap To protect the aftermarket Tweeter. Next time I do a speaker upgrade I will make a video of the outputs on the scope so you can see the crossover points.

 

Do you maybe mean 3.8 picofarad cap? Resistance isn't a measure that makes sense to specify on a capacitor...

Generally using just a capacitor is going to function as a very ****ty crossover. It will sound far from ideal and at high volumes won't protect your tweeter. This won't so much give you a crossover point as it will give you a vague and very wide crossover region.

 

What do you think is doing the work in a passive crossover now.

I have a focal Xover at work. Ill show you what crossing over the tweeter now.

If you separate the focal 4 inch poly glass coax there a cap in that tweeter.


On the rear speakers if you can use the year drop pods is you separate the coax. There a screw behind the focal label. Remove it ant the tweeter comes out. Attach to factory wires and mount and your componet mount done cheep. No abs plate needed.

On that tweeter is a cap. Do it I dare you.

 

I post the photos of a crossover on Monday. I'm on my mobile app FYI.

 

There is way more to a crossover than just a capacitor. I can elaborate on this if you want.

Most tweeters will have a cap on them purely to try to protect it in a worst case situation, they are not intended to be used in place of a crossover. Similarly woofers will have an inductor or even a basic RLC circuit on board.

(I have designed and built crossovers from scratch, and I specialized in this area when I did my electrical engineering undergrad)

 

Remember we're talk down and dirty cheep DIY install. Not high end install.

My suggestions will work.

We can talk theory all day but I have practical application experience.

Back in the day we use to use caps and coils and power 8 speakers off a punch 45.

We going old school. I have a video we did in a BMW using same theories.

 

can you give us more detailed suggestions shane? right now it seems secret asian man is making more sense...because i tend to agree that caps usually use farad as units not ohms...

 

what we are looking for is not competition sound system booming and shaking the building..we are looking for a good sounding system fit for a porsche. right now we all agree that the supposed upgrade bose is really a crappy system. we appreciate all who seriously want to share their knowledge and experience to create this acceptable system. we will discover those who simply want to mess up this thread by suggesting something that will lead us away from this good system.