Is heavier deadener better??

[0ur80r0s]

I started a tread about how much weight a door can take and got some good info on it....so it seems like 20-25 lbs or so would be like the safe upper limit for most cars hinges to take over time of the car. some guys have like 60 # and a one whole roll of deadener in there! :o

so my question is about heavy deadener and is it better? I'm new to all this and want get it done right on my first time out but I just cant find good info on which deadener is the heaviest. Or maybe i don't want heavy deadener but just lots of layers of it?

Sorry i searched and all just more questions then good answers for me :cool:

[Rudeboy]

You are going to have to be a little more specific about what you mean by heavy vs light. One of the primary functions of a vibration damper is to add mass to a vibrating body thus lowering its resonant frequency. It's pretty much beyond the abilities of us aftermarket knuckleheads to identify those few situations in which this isn't desirable. The other mechanisms for vibration damping also vary more or less with weight so you are almost asking if more effective deadener is better. I'd say yes :)

[0ur80r0s]

One of the primary functions of a vibration damper is to add mass to a vibrating body thus lowering its resonant frequency.

So is it best to get a deadener that has more mass than one that has less mass??? I think thats what im trying to get at here, sorry kind of a dumb question i know. :cool:

i just figure i need a lot of mass like these other guys i see and want to spend my money wisely when it comes to selecting the best deadener. like on your website i see Dynamat has the most pounds per ft2 at .70, so that would mean more deadening with less deadener applied, right?

[Rudeboy]

So is it best to get a deadener that has more mass than one that has less mass??? I think thats what im trying to get at here, sorry kind of a dumb question i know. :cool:

i just figure i need a lot of mass like these other guys i see and want to spend my money wisely when it comes to selecting the best deadener. like on your website i see Dynamat has the most pounds per ft2 at .70, so that would mean more deadening with less deadener applied, right?

Dynamat isn't actually the heaviest, but yes mass/area is an important consideration. Reducing weight is more a question of approaching the issue intelligently instead of selecting your sound deadener for lighter weight. Are there alternatives that will get part of the job done? As an example, bracing can be very effective. If you can use tubular aluminum or steel or even plastic for this, you may be able to reduce your deadening needs significantly.

The centers of panels are much more prone to resonance than the edges or areas near bends or welds - don't just build up even layers, target your deadening.

When WhiteRabbit is talking about removing some deadening from his doors to get rid of weight induced sag, bear in mind that he was starting with some layers of Damplifier followed by an entire ROLL of RAAMmat IN EACH DOOR. That's well in to the extreme realm.

[npdang]

Depends what you're using it for. Mass loading to reduce the resonant frequency, obviously more mass is better. If you're absorbing sound thicker, but not necessarily heavier is better. And if you're looking for good isolator, you'd want something with more inherent dampening, not necessarily mass.

[0ur80r0s]

Dynamat isn't actually the heaviest, but yes mass/area is an important consideration. Reducing weight is more a question of approaching the issue intelligently instead of selecting your sound deadener for lighter weight.

Oh ok i just saw the most was .7 on the specs page. Do you know which one is? :cool:

i just don't know if i should be buying deadener by the weight or by the ft2? Do you know what i mean? If i can just cover the most important areas with more mass in less ft2, to me that makes more sense. :confused: where is the newbie forum, lol??!?!?

And i must say thanx for your guidance here! :cool:

[Rudeboy]

Oh ok i just saw the most was .7 on the specs page. Do you know which one is? :cool:

i just don't know if i should be buying deadener by the weight or by the ft2? Do you know what i mean? If i can just cover the most important areas with more mass in less ft2, to me that makes more sense. :confused: where is the newbie forum, lol??!?!?

And i must say thanx for your guidance here! :cool:

Damplifier Pro is heavier. You should never compare price per ft² alone. You want butyl adhesive and aluminum foil - the thicker the better on the foil. Among butyl/aluminum products, price/lb is a more useful value metric. Cascade claims that their VMax is more effective per unit of mass because there are ceramic spheres in the adhesive, but that is pretty hard to substantiate. It's almost always best to pick a quality product and use as much as you need to get the job done. It's not as precise a process as we might like.

[0ur80r0s]

Damplifier Pro is heavier. You should never compare price per ft² alone. You want butyl adhesive and aluminum foil - the thicker the better on the foil. Among butyl/aluminum products, price/lb is a more useful value metric. Cascade claims that their VMax is more effective per unit of mass because there are ceramic spheres in the adhesive, but that is pretty hard to substantiate. It's almost always best to pick a quality product and use as much as you need to get the job done. It's not as precise a process as we might like.

Oh I was going by these;
Dynamat Original Net Measured Lbs ft2 (w/o release paper) 0.70
Damplifier Pro Measured Lbs ft2 (w/o release paper) 0.49

Ok i think i got it so far now. My mind is sort of tied to the weight as a big factor by there are others out there too so i will look at Cascade and Second Skin as i've read the most about how well they work, plus they are butyl and have the ticker foil to them.

:cool:

[lunchmoney]

Oh I was going by these;
Dynamat Original Net Measured Lbs ft2 (w/o release paper) 0.70
Damplifier Pro Measured Lbs ft2 (with release paper) 0.49

Ok i think i got it so far now. My mind is sort of tied to the weight as a big factor by there are others out there too so i will look at Cascade and Second Skin as i've read the most about how well they work, plus they are butyl and have the ticker foil to them.

:cool:

I used about 15 square feet of Second Skin Damplifier Pro in each front door... unbelievable difference. I highly recommend it.

[Rudeboy]

Oh I was going by these;
Dynamat Original Net Measured Lbs ft2 (w/o release paper) 0.70
Damplifier Pro Measured Lbs ft2 (w/o release paper) 0.49

Ok i think i got it so far now. My mind is sort of tied to the weight as a big factor by there are others out there too so i will look at Cascade and Second Skin as i've read the most about how well they work, plus they are butyl and have the ticker foil to them.

:cool:

All good stuff - just stick to Dynamat Xtreme if you are going the Dynamat route. Dynamat original is obsolete junk compared to modern products.

[DIYMA]

I am going to answer the question of the title before reading the rest of this thread. I will try to make it as general as possible.

Assuming that by sound deadening, you are referring specifically to vibration damping, then the answer is, mostly yes.

All thing being equal, yes. Heavier dampers will yeild better results than lighter materials of the same nature.

WHen comparing constraint layer viscoelastic damping systems, heavier GENERALLY will yield better results, provided there is some conversion of energy happening. CLVED by nature convert vibrations to heat so a heavier one, should in theory provide better vibration damping results.

Look at the original Dynamat material- an old fashioned mass loading damper.

This was a decently thick, decently heavy mass loading material, but due to the make up of the material, since the product was not viscoelastic and had no constraining layer, it was unable to convert the vibrations in to heat, and thus, was only good for the added weight.
Adding weight or mass to a panel lowers the resonant frequency of that panel making it more difficult to resonate with the same given energy is helpful, just not efficient.
A constraint layer damping system with a nice thick foil will yield much better results than a heavier system with thinner foil.
The key comes in the density of the adhesive and the thickness of the foil.

Both the weight/mass, and the conversion of energy play a part in CLVEDs but when used together will yield much better results.

If the 2 products are old fashioned mass loaders than the heavier one will work better. Not as much to figure out there.

[Airforceyooper]

You can look into a deadeners "acoustic lost factor." Most companies offer this information. A few don't. I like second skin, but I e-mailed them asking for this information to compare to other companies and they never replied. Raamats reply was, "we know ours is good and that's good enough for us." Which, is not good enough for me. I did find one company, I won't promote so nobody thinks I'm trying to advertise for them or anything, but there is at least one company out there who has very good numbers on par with Dynamat extreme for half the price. Some companies suck really bad. Others have great numbers but are very expensive. I found the deadener I'll be using. Great numbers and even better price.

[Rudeboy]

You can look into a deadeners "acoustic lost factor." Most companies offer this information. A few don't. I like second skin, but I e-mailed them asking for this information to compare to other companies and they never replied. Raamats reply was, "we know ours is good and that's good enough for us." Which, is not good enough for me. I did find one company, I won't promote so nobody thinks I'm trying to advertise for them or anything, but there is at least one company out there who has very good numbers on par with Dynamat extreme for half the price. Some companies suck really bad. Others have great numbers but are very expensive. I found the deadener I'll be using. Great numbers and even better price.

Here's the problem with that - many of the ALF numbers posted are bogus. Either they were just made up or the testing methodology was modified to give a competitive advantage. Several legitimate companies either have and won't release results or haven't bothered to have testing done because real results will look terrible next to the inflated numbers already out there.

Unless you can compare full reports, from labs whose credentials you can verify, raw ALF numbers are worthless. I've seen the exact same product, sold under different names, displaying wildly different numbers, both claiming to be ASTM E756 compliant @ 200 Hz. Sorry.

[internecine]

why is a thicker foil layer better?

[Rudeboy]

why is a thicker foil layer better?Thicker foil adds more resistance for the adhesive deformation/return mechanism at the foil/adhesive interface. That's the essence of constrained layer viscoelastic damping. It's also likely to improve the material's performance as a barrier. It also might add more rigidity to the panel. The thicker it gets the harder it is to work with so there is a practical upper limit.