GR Research No Res alternative?

[utubecomment21]

Alibaba is your best bet, as that's where 99.9% of this stuff comes from anyway.

Do not buy that cheap dollar stuff from the local hardware store. It's cheap for a reason!

And do not buy the branded stuff from GR, NVX, Dynamat .... again, it all comes from China anyway, or in the case of Dynamat, it's inferior & overpriced!

 

[utubecomment21]

Or you can just use Mineral Wool

 

[Dave Bullet]

Impedance sweep of a sealed triangular shaped 3 way tower, with bracing, and 10mm gym floor tile on walls with pillow stuffing Walls are 18mm MDF. Front baffle double layer with scalloped backside for midrange airflow. Smoothness tells me there aren't any inherent problems (low power sweep may not show such problems however):

 

[Rick Sykora]

Impedance sweep of a sealed triangular shaped 3 way tower, with bracing, and 10mm gym floor tile on walls with pillow stuffing Walls are 18mm MDF. Front baffle double layer with scalloped backside for midrange airflow. Smoothness tells me there aren't any inherent problems (low power sweep may not show such problems however):
View attachment 331517

If you have a mic, try pointing it at each of the sides and run sweeps at some low to moderate level.

 

[Rick Sykora]

Or you can just use Mineral Wool

This is a hack job. Without focus on the problem it is throwing solutions around. Not clear whether his speaker has a panel and/or some other resonance. Nice video production though!

Mineral wool can be useful but has various types that affect absorption in varying frequency ranges. It is not a panacea.

 

[Dave Bullet]

If you have a mic, try pointing it at each of the sides and run sweeps at some low to moderate level.

I presume - much the same as nearfield port / driver sweeps, the proximity of the mic / dominance of the nearfield measurement makes room influence irrelevant, same would happen for panel resonance sweeps? An inbox measurement is problematic as these are sealed.

 

[Rick Sykora]

I presume - much the same as nearfield port / driver sweeps, the proximity of the mic / dominance of the nearfield measurement makes room influence irrelevant, same would happen for panel resonance sweeps? An inbox measurement is problematic as these are sealed.

Yes, nearfield is a must.

 

[beagleman]

Just brace the enclosure and this is not needed. Unless you are making your enclosure out of sheat metal....

Laughably,, as a teen I had a set of speakers I picked up at a dump, that WERE honest to god sheet metal boxes with fake woodgrain on them!

They were actual retail made speakers, no idea brand now, but obviously from some 70s compact stereo set up, used a 4" full range inside with a cheap bass reflex slot at bottom
They rocked out like NO speaker ever!! Vibrations and such were huge with ANY bass note, fun but OMG so crappy!

 

[Count Arthur]

Has anyone tried MLV: https://quietliving.co.uk/mass-loaded-vinyl/

I think there are self adhesive versions.

 

[Rick Sykora]

Has anyone tried MLV: https://quietliving.co.uk/mass-loaded-vinyl/

I think there are self adhesive versions.

I have not, but as some know, have tinkered with butyl rubber sheets. Butyl rubber is used in automotive apps. The sheets are used to dampen panel vibrations but it also comes in caulk form. The caulk is what is used to seal windshields in place. Looking for lower cost, others have applied vinyl tiling. If comparably effective (may depend on frequency and amplitude), MLV looks like it has potential. Thanks for sharing!

 

[carbidetooth]

No Rez is proprietary only in the way it is configured, and Danny does have it made to his spec. The damping layer is positioned differently than the similar product from Parts Express. I suspect both are made by the same USA company. If guessing, I'd say it's closer to MLV than other products mentioned. When I cut on my bandsaw with steel blade I see small sparking and it dulls blade significantly faster which leads me to believe that it has aggregate of some kind in it. The "mass" in MLV is often aggregate of some sort. They may even be the same in that regard. The foam layer is essentially the same as far as I can tell. Parts Express now uses the "Sonic Barrier" name on many products, many of which I've used.

Asphaltic dampers are often use on automotive panels. As the name suggests, it has asphalt base which is relatively inexpensive. Kind of a contained goo sheet...much different than vinyl. It's also used in some sealing products used in building of homes and commercial structures. One brand name I've used is Vycor Plus. Vycor also makes a product called Vycor Pro which is butyl. Butyl is synthetic rubber. To my knowledge, vinyl floor tiles and sheet goods have no added aggregate mass but can be pretty dense...some more than others. Linoleum is not vinyl and vice versa, even though the names are often used interchangeably. Linoleum was originally formulated with linseed oil as its base, hence the "lino" part of the name.

Perhaps Butyl was used in old windshield surrounds and I know it's used extensively in the RV industry in various forms. Modern windshields are installed with Urethane and become an actual structural member in many cases. Urethanes and polyurethanes can be extremely strong, but it's not all the same product. Rather it has various forms that make the base polymer used in many and varied applications.

 

[kemmler3D]

As I understand it, actual damping requires some kind of shear within the material when waves pass through it. On DIYAudio it's common to see suggestions for layers of plywood or MDF to be sandwiched with Green Glue which apparently never fully solidifies, allowing the layers to move relative to each other and introduce shear in the glue.

I think multiple layers of material with very different densities (MLV, foil, foam) produces similar effects, but I'm not sure.

 

[carbidetooth]

As I understand it, actual damping requires some kind of shear within the material when waves pass through it. On DIYAudio it's common to see suggestions for layers of plywood or MDF to be sandwiched with Green Glue which apparently never fully solidifies, allowing the layers to move relative to each other and introduce shear in the glue.

I think multiple layers of material with very different densities (MLV, foil, foam) produces similar effects, but I'm not sure.

What you're describing is "constrained layer damping" or CLD. It is one of many ways to damp a surface or enclosure. Its effectiveness is mitigated to varying degrees when both the inner and outer layers contact one another. CLD is defined as having some sort of viscous layer sandwiched between more rigid layers. I used Green Glue in a room I wanted to reduce sound transmission in and while kinda sticky, it's not structural glue nor does manufacturer claim it is. Makes it hard to achieve complete isolation of inner and outer layer such as seen in a speaker cabinet.

To a much lesser extent, laminating various sheet goods can have the effect of "short-circuiting" vibration and resonance but it's not CLD.

In my experience, there's a lot of lore in both the woodworking and audio worlds that has some basis in fact or kernel of truth but is extrapolated into little in the way of actual performance.

 

[hex168]

As I understand it, actual damping requires some kind of shear within the material when waves pass through it. On DIYAudio it's common to see suggestions for layers of plywood or MDF to be sandwiched with Green Glue which apparently never fully solidifies, allowing the layers to move relative to each other and introduce shear in the glue.

I think multiple layers of material with very different densities (MLV, foil, foam) produces similar effects, but I'm not sure.

A pretty thorough test of various practical CLD methods:

Box Construction Methods | somasonus

www.somasonus.net

 

[ThatSoundsGood]

Has anyone tried MLV: https://quietliving.co.uk/mass-loaded-vinyl/

I think there are self adhesive versions.

I use a layer of mass loaded vinyl in between plywood and MDF. My speakers are really heavy but the walls are really dead from this. Then I use sonic barrier inside. Sonic barrier really deadens the inside of a speaker. I don't have any comparative measurements but it's a really noticeable difference. You can see the vinyl layer in these pictures. I had not put the Sonic Barrier in yet.

 

[Chrispy]

I know No Res is usually touted as some of the best material to prevent ringing/vibration in a speaker but its also ungodly expensive. This stuff isn't exactly cheap either but I like the idea.

Doesn't seem there are many great alternatives out there that follow its 2-layer design. Then I came upon this stuff. Made for car audio but looks like it may very well work just as good or better.

Anyone ever tried this stuff out for speaker dampening?

Video of it:

Link:

https://www.sonicelectronix.com/item-170005-NVX-SDRF20.html

You saying Danny has an actual useful product?

 

[Rick Sykora]

What you're describing is "constrained layer damping" or CLD. It is one of many ways to damp a surface or enclosure. Its effectiveness is mitigated to varying degrees when both the inner and outer layers contact one another. CLD is defined as having some sort of viscous layer sandwiched between more rigid layers. I used Green Glue in a room I wanted to reduce sound transmission in and while kinda sticky, it's not structural glue nor does manufacturer claim it is. Makes it hard to achieve complete isolation of inner and outer layer such as seen in a speaker cabinet.

To a much lesser extent, laminating various sheet goods can have the effect of "short-circuiting" vibration and resonance but it's not CLD.

In my experience, there's a lot of lore in both the woodworking and audio worlds that has some basis in fact or kernel of truth but is extrapolated into little in the way of actual performance.

I tried some CLD approaches in subwoofer cabinets. Most of the time it made no difference or was worse. As mentioned earlier, there are inexpensive ways to measure the effect that any damping material might have. If it cannot be captured with a microphone, not likely our ears are going to detect. Liquid Nails has been touted as a CLD layer, and Danny endorses it for the Encore. I did not find it effective and recall you favored wood glue too. CLD may be effective but suspect it requires more surface area than is practical for most speaker applications.

No-Rez is likely useful albeit pricey. As with too many other situations, Danny claims superior results without evidence. He has a microphone and could readily compare No-Rez to alternatives. If he has tested and not published, it likely means his claims are not credible and/or their lack obvious differentiation. If No-Rez is so vastly superior, there would be one or more vendors touting its virtue. It lacks even one endorsement from any major vendor or independent lab. To be fair, Dayton Audio does not offer any specifics on Sonic Barrier, but it does have a stated 1 year warranty!

 

[Rick Sykora]

MLV is comparable in price to butyl rubber but half of what Sonic Barrier/No Rez offer as they incorporate open cell foam too. With adhesive backing, they are more than twice the cost of MLV. Unless I had a really large cabinet to dampen, would stick to the Sonic Barrier with PSA.

 

[ta240]

This is a hack job. <snip> Nice video production though!

That sums up most of youtube.

 

[ThatSoundsGood]

I tried some CLD approaches in subwoofer cabinets. Most of the time it made no difference or were worse. As mentioned earlier, there are inexpensive ways to measure the effect that any damping material might have. If it cannot be captured with a microphone, not likely our ears are going to detect. Liquid Nails has been touted as a CLD layer, and Danny endorses it for the Encore. I did not find it effective and recall you favored wood glue too. CLD may be effective but suspect it requires more surface area than is practical for most speaker applications.

No-Rez is likely useful albeit pricey. As with too many other situations, Danny claims superior results without evidence. He has a microphone and could readily compare No-Rez to alternatives. If he has tested and not published, it likely means his claims are not credible and/or their lack obvious differentiation. If No-Rez is so vastly superior, there would be one or more vendors touting its virtue. It lacks even one endorsement from any major vendor or independent lab. To be fair, Dayton Audio does not offer any specifics on Sonic Barrier, but it does have a stated 1 year warranty!

To be fair, Danny shows different measurements in the waterfall charts before and after his crossover changes and adding no rez. So, he has done measurements there and I think it's fair to say that the waterfall chart can be an indication of reduced resonances in the cabinet. I will also say that I don't think any of these products will work very well (or at all) on sub frequencies. I would go so far as to say that they wouldn't do much below 300 or 400Hz, so they aren't really meant for internal standing waves or compensation for improperly braced cabinets. But they do well to deaden stuff in the 800Hz and above range, which could be very helpful on dampening internal resonances that come out of a port or a mid range enclosure as well as through cabinet walls (especially in poorly braced cabinets). I can hear a clear difference with the sonic barrier on the inside of a cabinet and I use it on anything that is producing frequencies above 300Hz. I have not done any clear testing on this but just clapping or snapping inside of a cabinet shows a massive difference.