How can I make my own acoustic materials?


I was wondering if I could make my own diffusion panels like those that RPG makes. Do you think these could be as effective as the RPG's? or the RPG's have something special?
Also, is there any good book or source in the web about how to construct acoustic treatments? I'd appreciate your help on this matter. GRACIAS!
adal1108
Try checking out this site. Jon is an electrical engineer and works for a company designing Pro Sound equipment. He is well versed in pretty much every aspect of sound reproduction. Hope this helps... Sean
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http://members.nbci.com/Jon_Risch/index.htm
Yes you can. Here is what you do, Go to Home depot and ask them for Duct Board it comes in 4`x8` sheets which is coated fiberglass insulation and you can cut them anyway you like. Then you can go to a fabric store and pick out what ever material you prefer to cover them. Or you can call a card board facility and ask them for the sheets of cardboard that have the ripples in them and they are 2" thick. The duct board will be a better sound barrier than the card board but they will both help you acheive sonics benifiets. Good Luck P.S: It may be cheaper to just purchase the panels. Also I just remembered that if you go to an acoustical company they may have panel or the foam sound panels left over from a job they can sell you very cheap. I got mine that way. The place is called viber sceince in Branford Connecticut. :-
Be sure to ask Jon Risch about making your own room lenses. They work fantastically well and work best with no other room treatment. They are quite easy to build and Jon has the necessary info.
I have detailed DIY designs for three types of RPG-style diffusors which I'd be glad to email you. I used 1/2" medite for the first and have used Styrofoam (which does a fair amount of absorbing along with diffusing, more or less like RPG's Abffusor) after that, for lighter weight, easier construction. But any board could be used. My clones of RPG's Skyline work as well as the real thing, as far as I can tell. But then all my models are sure to work--the basic design behind them is precisely the same as RPG's. A little of the theory can be found in F. Alton Everest's "Sound Studio Construction on a Budget", maybe also in his "Master Handbook of Acoustics", but be sure to get the 4th edition. Jon Risch has detailed instructions for tube traps a la ASC but the construction looks a lot messier than my DIY projects--which do, however, call for a table saw or the like to cut the pieces. Good luck!
Goto www.decware.com (the infamous Zen amps website). They sell plans for room acoustic treatments. I just ordered plans for corner bass traps. Very cool...
If i remember correctly, someone on the Asylum did a "shoot-out" by setting up a room following Jon Risch's directions and then using Steve Deckert's directions. They brought in a varied group of "local audiophiles" and listened to both groups. The group pretty unanimously picked Risch's set-up as being far superior in terms of sonics, especially imaging. Like anything else though, personal tastes and installations vary. The fact that Jon "gives" his designs away doesn't hurt anything either : ) Sean
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If it's not documented, it never happened...if it's not validated, it's useless...that's what any QA officer would say about that. I bought the corner bass traps plans because they are massive(121 lbs)and right now the bass frequencies are travelling to the top and bottom apartments and that is not good. Steve assured me that even footstep sounds would be absorbed by the bass traps. I don't think he's a Vodoo man. Far from it. I trust his design.

Careful with rockwool inside living spaces: It is molten granite spun over rolls. If it's dry it will release asbestos-like particles in the air. Not good.
Psychicanimal, i have nothing to gain by promoting or belittling either Jon Risch or Steve Deckert. Both are making a valiant attempt to help people out. One does it by sharing his knowledge, designs and offering advice / guidance for free while the other makes / sells / markets various products and services. You be the judge as to who is more likely to "hype" their product. In my eyes, it would be the one that stands to make money.

As i mentioned, the results of that specific test were documented somewhere on the Asylum. If i can remember correctly, there were over a half dozen audiophiles that were involved in the listening test.

Either way, i wish you luck in your project. I hope that the bass traps turn out as your expecting and solve your problem. Sean
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Thanks, Sean. I have my neighbors complaining and it's a brick building!

Research costs money. Nothing's free. I talked to Steve yesterday and these people went through several prototypes before reaching the current bass traps. I don't think $29.95 is nowhere near a rip off for their time and efforts.

I would be wary of someone giving things for free because of lack of funds to sustain R&D, but that's just me...

Although I work in sales, I am a professional scientist (shit happens).

This is the formula:

Quality Control + Quality Asessment = Quality Assurance

Most people (even in science) equate Quality Control with Quality Assurance. Totally wrong. Control involves design & execution (process control), asessment oversight. The combination assures quality. If this is followed anyone can make good progress (ask the Japanese!).

Steve told me that he has made mathematical analysis of Risch's bass traps vs his designs. It would take many many many to equal one of his bass traps (according to his math, that is). Steve talks science when it comes to this subject. Totally non Voodoo. That's what I look for. After all, it's acoustics; it's governed by the laws of physics, right?

Peace to all,
Since we were discussing about tests and validation, here are some thoughts on sustainability, validation and quality control:

I was looking at the classifieds here in Audiogon and I ran into an ad for a 'cable and interconnect cooker'. This is what the website says:

"The break-in process is believed to be due primarily to current flowing through the conductors of wiring components. Dielectric stress caused by a voltage difference between the conductors is also believed to be of some benefit. The fact that it takes many hours of in-system use for wiring components to break in is primarily due to the low-level nature of audio/video signals from normal program material."

When one reads for quality assurance (and I did it for a living) one must watch for empty, inconclusive statements.
The above parragraph lacks sustainability, proof, or any other data sustaining what it says. The very first sentence is a joke! Believe me, I've seen documents presented by chemistry labs with similar statements! Just keep your mind open...
Here's a few things to take into consideration:

First of all, Jon works for a major corporation that designs sound gear that is used by professional musicians, recording studios, pro sound reinforcement and "hobbyist" musicians. As such, he has access to EVERY imaginable type of test procedure / test equipment / computer simulation product available to a company of that size & nature. He uses this equipment on a daily basis as part of his job of building & designing both electronic and acoustic based products.

Previous to doing this, he had worked for several other manufacturers in the audio industry. As such, he has over 25 years in the industry. On top of that, he is a degreed EE and a member of the Audio Engineering Society with published papers in their journal and several different patents to his credit. Needless to say, he is well educated in the field, has TONS of education and first hand experience with THOUSANDS of testimonials / posts of praise to his credit. If you want "science", rattle off some technical questions to Jon over at the "cable asylum" and see if he can answer them. I'm sure that he can give you more than your fill of terms like velocity factor, dielectric absorption ratios, conductivity in mho's, reactance at various phase angles, etc...

Don't get me wrong as i DON'T "worship" the guy. He simply has very worthy credentials and lives up to them.

Secondly, some specific "cable burners" DO work. Regardless of the claims, hype, lack of understanding, etc... the sonic results can be QUITE obvious. I do agree that the text used in that specific case is "mumbo jumbo" and could have been worded in a far better manner.

Finally, ANYONE can talk a good game. Con artists make a living out of doing such. Just because someone has "marketing skills" DOES NOT mean that they can support their claims or deliver the goods when called upon to do so. Just because one can talk the talk doesn't mean that they can walk the walk. Unfortunately, some of us have learned the hard way that some folks are more "charlatan" than "genius". Sean
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This is getting into another subject, Sean...those guys are using that 'mumbo jumbo'--which they headline as a 'technical discussion' to sell a $649.00 piece of gear!

For that kind of money I can get the tonearm fluid damper for my Technics 1200 TT ($149), an Ortofon low output MC super 15 MK II ($225), a pair of Tekna Sonic C-10 fins for my JMlab speakers ($99) and still have money left for albums!

Crazy, isn't it?
I agree that some "tweaks" are outrageously priced. Keep in mind that even though you might be able to go out and pick up all of that stuff mentioned for about the same price, you STILL might not be hearing what your system (especially your cables ) is capable of doing. Believe it or not, it is the "truth".

For the record, one can make a VERY heavy duty "cable burner" for well under $100 if one was "handy". It might not be as pretty as the fancy mass produced ones, but it WOULD work. Sean
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I've just got my blueprints for the corner bass traps. Very well designed. I talked with Steve Deckert this morning about the particulars of my apartment setup. He was very helpful about helping me live peacefully with my neighbors...I've already recommended him with two of my audio salesmen. Definitely worth doing business with.