Hi Mike, I agree the blankets are not a complete treatment. The mid/high quotient is what I found it effective on also. Rock Wool whether in the bag or not is a known resperitory hazard and sheds friable debris to small to see. I would have to advise not using it in any open space due to the Material Safety Data that is published on it. It probably does absorb better but industrial fibers are dangerous. And wool blamkets can be a bit expensive. Treat to taste I guess.

ORIGINAL: mike_mccue

Craig,

Markertek's moving blankets and Rock Wool are not even in the same ball park. I've got six of those Markertek blankets in my van. I bought them for sound but immediately determined that an old wool army blanket worked many times better. The only time I've heard a moving blanket cut a resonance is in hards surfaced rooms that have lots of activity in the mids and highs.

If you really want to use sound blankets... get the heaviest wool blankets you can find.

There's no reason to think rockwool is messy. You can leave it in the shipping plastic and it will still outperform Markertek's moving blankets by many factors.

All the best,
mike

hey, I made a diffuser illustration once, I want to share as well:



I whipped it up and offered it too someone in Germany who had written a nice series of articles about acoustics and diffusion and was using an illustration that did not match his text description. I don't think he ever made use of it.

This is a prime number based "skyline" diffuser design that he was describing.

best regards,
mike

Rock Wool whether in the bag or not is a known resperitory hazard and sheds friable debris to small to see. I would have to advise not using it in any open space due to the Material Safety Data that is published on it.

I am not sure why rockwool is a hazard? If I build a bass trap panel like this:
http://www.youtube.com/watch?v=iyYUpkpL0gw

the rockwool will be inside the fabric, so that shouldn't be a problem, right?

Papa, thanks for the explanation about absorbers. I do already have a bookcase in my room, although it's a thin one so it doesn't cover that much of the wall. I might think about using a bigger bookcase on one of the walls if that will help...

I won't comment on the room treatment stuff, that is already being covered very well by folks more knowledgable than me. But are you sure your problem is actually room related? It seems like I'm always late to the party, and I often go off on tangents, but it sounds like your problems are more "mechanical" then they are "acoustical".

Ringing toms? A new drum tuning or different drum head might help. In a pinch, put a handful of cotton balls inside the drum - as they will more gradually damper the ringing. If you want to kill all ringing (and in my opinion all of the wonderful tone), you can tape various fabrics to the heads themselves (please don't resort to this, it sounds ugly).

Weak Bass Drum? Is the drum tuned too low? If the head is too loose, it won't have enough tension - which means it is not conducive to vibration. Sometimes the answer to getting a 'fatter' kick drum is to actually tune it tighter. Is there a big pillow stuffed inside the drum and pressing up against the heads? I guess that might be OK if you're after a real tight & attack oriented sound and you throw a close mic up in there. Have you tried a resonant head without a hole cut in it? (that one is guaranteed to offer some instant "boom").

SM57's as Overheads? It sounds like you already know this is not ideal. You can either make the best of it until you can afford a decent set of condensers. There are some minor improvements you can make with do it yourself SM57 modifications, but it's no silver bullet.

hmmm... I might upload an mp3 of my drum recording and let me know what you think

mike, that's a great diffuser picture, thank you! i think i understand what needs to be done better now... i think i'll follow your advice and start with building bass traps, and then hopefully eventually include some diffusers to avoid having a dead sound

i am trying to post my room modes using modecalc but i don't get how i can attach a file here yet...

ORIGINAL: amrkadry

For the OP: To clarify the confusion between "aborbers" and "diffusers" I did a quick AutoCAD drawing of what the side view of a "diffuser" might look like...Properly designed (and properly placed) diffusers with, in most cases, properly placed bass traps, can do wonders to "clean up" the sound of a room.



Believe it or not, a floor-to-ceiling bookcase--properly placed and stocked with the right books--might serve you well as a diffuser. All things depend on your room and speaker/listening positions.

There are many things you can do to improve the room(s) you're working in. If you're serious about attaining a quality sound, without the undesirable room properties, you'll just have to experiment to find what works best with your equipment.

that's the post what i responding to

Umm, I think you are confused about what posts you're responding to...I was responding to the GMGM post...

Just a couple of things to watch (listen) for and to think about while putting the treatment together:

The air space behind those bass traps is very important. Don't just mount them flat, frame them so they give you space (unless you are going for the "kill everything dead space")

The corners and the ceiling/wall interface is a great place to start on controlling deflection. If you cannot afford wedges get a couple of 12' cardboard tubes that carpet comes rolled on, fill them with your choice of material (newpaper, foam, packing peanuts, dollar bills) and wrap them with scrim or upolstery fabric for looks. It is a guerilla style way to get it done but it greatly tames those corners and it's easy to cut and fasten to the substrate.

The positioning of the traps will change things drastically. Move them around, use some of the intuitive suggestions on the links and test the orientations before you chose your final positioning.

Don't forget the ceiling right above the drum set. Huge area of common, uncontrolled reflection. Again, a combo trap/passthrough in that position, with some "air" between it and the ceiling will go a long way in controlling that ringing and boom up where the OH's live.

If it ain't broke don't fix it. We have a fairly simple, yet complicated room treatment scenario wherein the drum room is actually a room within a room and there are passthrough filters and deflection filters as well as corner killers and bass traps. There is/was an over-head pass through panel under the overhead ceiling trap that we found was our "secret to success" when I reframed/restuffed it for a more "pretty decorator look" and it KILLED the room in a room (badly I must say). Needless to say, the old panel(s) went back up and the "custom tricked out pretty one" is in the side yard rotting. If you get your room in decent shape don't go gettin' all Martha Steward on it

Now everything I just described is more for the "capture" portion of our operation, not so much for the mixing side. We do have some back wall traps and such but we mainly wanted to get a live feeling, isolated room for the drummer, which also works great for VOX finals. If you put a piece of wood floor in there it really kicks an acoustic guitar or a female voices dynamic quality and we can open up (pull) some of the filter panels for added open-room reflection when the need arises.

Room Treatment- Try it, you'll like it.

Luck

Rock Wool whether in the bag or not is a known resperitory hazard and sheds friable debris to small to see.

Is this true? why do studios use it for bass traps? where is there a reference to back this up?

This is my setup:

"toms ringing ugly should be addressed at the instrument level first. "

absolutely

There is a good and easily readable tutorial on room acoustics by Ethan Winer:
"Acoustic Treatment and Design for Recording Studios and Listening Rooms"

Thank you, I did read through that but some things were still confusing to me, which is why I posted my questions here . Great link though!

If it ain't broke don't fix it. We have a fairly simple, yet complicated room treatment scenario wherein the drum room is actually a room within a room and there are passthrough filters and deflection filters as well as corner killers and bass traps. There is/was an over-head pass through panel under the overhead ceiling trap that we found was our "secret to success" when I reframed/restuffed it for a more "pretty decorator look" and it KILLED the room in a room (badly I must say). Needless to say, the old panel(s) went back up and the "custom tricked out pretty one" is in the side yard rotting. If you get your room in decent shape don't go gettin' all Martha Steward on it

I feel this way too which is why I am having the feeling that I should start slow and build things up. I'll start with a few bass traps in addition to the blankets I have, and if it sounds good then I'll let it be

I assume everyone else thought he was talking about the recorded audio coming back through his monitors in his mix position. If that were true, he could "tone down the volume" with a mouse click. Still, he thinks 'problems will be similar' in a bigger room, it just sounds to me like he's talking about the actual live & loud drum sounds themselves. Before anything is recorded. If I'm wrong then ignore me, but I'm only trying to help

Yes, that's right GMGM, I was talking about the sound IN the room, before being recorded. The toms ARE a bit ringy... kind of undefined. However I feel it's not the tuning as much as the room. I have taken my drums to a rehearsal studio before, and the same tom/snare drum which is loud and ringy in my room would sound way more controlled in the studio. The studio I go to is completely sound proofed and acoustically treated though, but still... my room makes things too ringy in my opinion.

So I'll try to get started on some bass traps and let you all know how it works out. I'm not sure yet if I will move to a different room, I feel that the second room is not that much bigger to justify moving my drums and recording equipment but we'll see.

Regarding the bass traps, is the tutorial on youtube a good way to start making them? Or does anyone have different suggestions?

This is the one I am talking about:

http://www.youtube.com/watch?v=iyYUpkpL0gw

Craig,

Have another smoke and relax...The info contained within the MSDS is designed to be in compliance with OSHA regulations (and to cover the manufacturers' respective a$$e$ in the event of a class-action lawsuit).

Properly constructed devices (walls, floors, bass traps, etc.,) using Rock Wool, in a properly ventilated area, are probably not any more of a respiratory irritant (for most people) than a pet cat. Nearly everything known to mankind is a potential respiratory irritant to some people. Considering the fall-out from the asbestos problems, I doubt it would be possible to distribute a similar product that is available to consumers at the "home improvement" level unless the governing bodies deemed it safe to do so.

For those who wish to be more "Eco-friendly", there are alternatives. CLICK HERE to read more. The concept they present is interesting.

ORIGINAL: mike_mccue

Ah Cotton!

My pet peeve... and favorite inexpensive fabric.

Cotton means PESTICIDE sprayed everywhere... KILLING everything. Like, not good!

How's that? I'm flying my greeny flag now :-)

Not sure where that's coming from. There are a lot of cotton fields in this area of the country and, somehow, flora and fauna have managed to continue living. What's the "KILLING everything" reference?

Now If I could only figure out what nasty substance they treat that cotton with to meet the ASTM fire safety specs...

The specs are listed HERE. If you need further information I suppose you could research the following:

BUILDING CODES
ICC - Evaluation Report #114/LARR - ICC ER 1134
Environmental Spec. - 1350
Building Codes - BOCA, CABO, ICBO, SBCCI

State of California Bureau of Thermal Insulation
(License # TI-1367 Reg # CA-T367AZ)

Did anyone see the TV show Eleventh Hour last night?

warm fuzzys,
mike

No. I was watching the World Series (and the interior of my eyelids).

"warm fuzzys"? Won't they create airborne particles that might be considered a respiratory irritant?

[EDIT] BTW, I am in NO way affiliated with the company referenced in my original post. I haven't purchased any of their products nor have I had any contact with them. I just happened to recall their product line from a time when I researching ideas for the design of a game room for a client.

For the record, I try to be as "eco-friendly" as possible (without becoming fanatical about it)--not for my benefit but for the benefits that my grandchildren, and their children, might reap...

I think you'll find it easy to learn that cotton is the row crop which gets the largest and most frequent doses of Pesticide.

Because it's not a food product it isn't regulated like something we might be concerned about eating. The only thing regulating pesticide application on cotton is the cost to yield balance of purchasing the pesticide product

However, there is the great irony that cottonseed that has been "reaped" from the cotton material can "magically" change status from by-product to "food" without having to have been considered a food crop while it's in the field. So all the cottonseed oil in the cheap junk food sent to the poor parts of town is not grown to the standard of any other food oil. But that's another story.

One may or may not choose to be aware of the millions of beneficial insects we share the planet with. The pesticide sprayed on cotton fields kills all of them. I care about that... I understand other people believe they have a manifest destiny to harvest the earths bounty with every advantage they can imagine. I like to stay friendly about that... but honestly it breaks my heart.

I live in a cotton belt as well. It's my contention that all those Boll Weevil monuments we are both familiar with are really institutionalized distractions to keep us thinking of the growth of the pesticide industry as a great victory. While in reality, the growth of the pesticide industry permitted hundreds (maybe thousands) of small rural towns to retain and continue development of infrastructures that provided benefits to so many people that the downsides of pesticide is ignored and the victory over the Boll Weevil has become considered a great step forward.

Why do you think "big cotton" spends millions on the "Natural" campaign?

Your in the biz, you know why money like that is spent. :-(

That's the point I'm trying to make.

all the best,
mike


edit spelling

Great, I enjoy beer!

big smile on my face,
mike

Thanks Craig and Papa for clarification.