!Help! with layout for 13'x26' open space

I am still searching for help on my attempt to for flush mounting my monitors. I have also asked about this in the section for speakers. viewtopic.php?f=12&t=11507 Any suggestions or advice???

I'm not the expert here on soffit mounting speakers, but what do you mean by "within 2 layers of GB". You mean the casing around the speakers? So far it looks like a plan. If your speakers are active you'd need an airflow behind the speakers to take care of the heat. Soundman has done some good research on soffit mounting, maybe had can add some comments.

Ro wrote:

I'm not the expert here on soffit mounting speakers, but what do you mean by "within 2 layers of GB". You mean the casing around the speakers?

"Within 2 layer of drywall" is refering to the drywall that would be installed on the interior framing of the control room. The pictures 1, 2, & 3 of the frames show the design with drywall and picture 4 shows the design without the drywall. The speakers have air ports in the front (KRK V8's series 2) so I don't think I will have to worry about the heat issue. The only holes I plan to put in the actuall wooden box frame will be for wiring. The big question is do I have to remove the R/C interior frame of the control room plan and hard mount the soffit frames to the side walls of the control room or can the frames be mounted to the floor and ceiling only

Good to see you back, Ro! Been missing your comments!

So far it looks like a plan. If your speakers are active you'd need an airflow behind the speakers to take care of the heat. Soundman has done some good research on soffit mounting, maybe had can add some comments.

Regarding heat and ventilation, definitely! I've been doing some testing on my new Adam A7 active speakers, and I was surprised at how hot they get. After running them all day at rather normal levels for a rather normal mixing session, they are more than just warm to the touch. They have big heatsinks on the back, and those get uncomfortably hot. I didn't have a thermometer on me (dumb!) but I'm going to take one next session and see hoe hot they actually get. These speakers are only rated at 100 watts, but of course the vast majority of that goes into heat, not sound. So it's basically like sealing up a 100 watt light bulb in a small wooden box, and leaving it on all day... So one thing I would definitely recommend if you have active speakers, is to allow for much more ventilation than you thought. More even than John shows on his suggestion for soffit ventilation. You are going to need a lot of airflow around the back of the speaker. I am even seriously considering making the soffit ventilation part of my HVAC system, or at least get some small, quiet PC fans to "help" the airflow along a little... I don't want damaged speakers or warping wood due to thermal overload. So that would be my suggestion: for active speakers, leave LOTS of space for ventilation, then figure out how that is going to affect your acoustics... I suspect that sealing your speaker in a box, then adding ducts to the box for ventilation, is something like adding bass reflex ports to a speaker cabinet! I'm not into speaker design at all, so I can't say what effect that has on the response. Hopefully the frequencies of those long ducts will be low enough to not be an issue, but maybe one of the speaker gurus can hip in with comments on that. Regarding using sheetrock for the soffit panels? I'm not convinced that is a good idea. It has the mass you need, but I'm concerned about how it will stand up, over time, to the constant high levels of vibration that the speakers will be pumping into it. That's a lot of vibration energy at very close range. Just a hunch, but I suspect that sheetrock might start disintegrating after a while. I think I'd stick with John's suggestion of heavy wooden panels, at the very least, but I'm going for concrete. - Stuart -

The speakers have air ports in the front (KRK V8's series 2) so I don't think I will have to worry about the heat issue.

Are you SURE those are air vents? They look like bass ports to me! You won't get any ventilation through a bass port! Those are 180 watt speakers. Lots of heat. They'll need lots of ventilation.

Soundman2020 wrote:

Are you SURE those are air vents? They look like bass ports to me! You won't get any ventilation through a bass port! Those are 180 watt speakers. Lots of heat. They'll need lots of ventilation.

Thanks Soundman. Small misunderstanding on my behalf. I will add vents for air passage to my plans.

Regarding using sheetrock for the soffit panels? I'm not convinced that is a good idea. It has the mass you need, but I'm concerned about how it will stand up, over time, to the constant high levels of vibration that the speakers will be pumping into it

Good point For this reason i used 38mm HDF (not MDF) a couple of times with very good success. In al these cases i decoupled the speaker from the soffit box. Until now i had never problems with heat with these Monitors: Alesis M1 aktive MK2, Yamaha MSP 10. I just use a simple hole for ventilation and the wireing without any problems. The point of the bassreflex of the holes/ducts is a good point. Maybee it was luck to have no negative effekt until now. I will think about it. By the way Stuart: How can you spend these unbelievable amount of time here in this board? Normal people have to work 40 hours a week. You have my respect my friend :D I like the way you think and learn :D cheers Mika

Soundman2020 wrote:

Regarding using sheetrock for the soffit panels? I'm not convinced that is a good idea. It has the mass you need, but I'm concerned about how it will stand up, over time, to the constant high levels of vibration that the speakers will be pumping into it. That's a lot of vibration energy at very close range. Just a hunch, but I suspect that sheetrock might start disintegrating after a while. I think I'd stick with John's suggestion of heavy wooden panels, at the very least, but I'm going for concrete. - Stuart -

What are you refering to when you say "soffit panels"?

By the way Stuart: How can you spend these unbelievable amount of time here in this board? Normal people have to work 40 hours a week. You have my respect my friend :D I like the way you think and learn

One of the advantages of being self employed! I'm on-line all day anyway, and it only takes a few minutes to browse the board and answer a question. When work is slow, I can take more time to do that. When I'm busy, then you don't see me here much! Thank you for the kind comments! - Stuart -

What are you refering to when you say "soffit panels"?

I'm referring to the large, heavy massive panels that directly surround the speaker itself. That 's what you make the hole in, to mount your speaker. You cut a hole in the soffit panel that is exactly the shape and size of the front face of the speaker. It acts as an infinite baffle, and therefore needs to be as large as you can make it (the experts recommend up to 45 inches all around, if you can!), heavy, dense, rigid, thick, etc. It must not vibrate. OK, 45 inches is probably impossible in a small studio, but you do need to give it as much surface area as you can, with the speaker surrounded by as much open, flat real estate as possible. In my case, I decided to go with concrete soffit panels, because I figure it will be easier to cast the strange shape that I need for my Adam A7's, than trying to cut it out of wood. Concrete also gives you much higher density and stiffness than wood, which is good. Sheetrock does have the density that you need, but I don't think it meets some other requirements. Mika is definitely on the right track with HDF, and 38 mm sounds excellent! His should work great. They must be pretty heavy and hard to work with, though, but who cares if they sound good! - Stuart -

I intend for the soffit panels made out of 3/4" Oak or Birch. It is supposed to be wood in my sketchu pictures. I didn't include the face of the soffit panel to better illustrate the framing. Any drywall I have referred to consist of the drywall that is on the interior frame of the control room. AR

I intend for the soffit panels made out of 3/4" Oak or Birch.

John can certainly say better than I can, but I think I'd go for something thicker than that. You do want lots of mass in your panels. The density of both birch and oak is around 0.6 to 0.7 g/cm3. The density of MDF (what John shows in his example) and HDF (what Mika is using) is around 0.8 to 0.9 g/cm3. The density of gypsum board is around 1.2 g /cm3, and the density of concrete is around is about 2.3 g /cm3. So to get the same amount of mass as Mika has in his 38mm HDF panels, you'd need 2 inches of oak or birch. Or just 9/32 of an inch of concrete! - Stuart -

Aloha, You could also sandwich another layer of 3/4 ply or MDF on the inside to help beef it up a bit :wink: Aloha 8)

Kendale's right. You can use the oak for the finishing layer to make it look AWESOME :) MDF and GB have about the same density and both are fine to work with. Have you asked yourself WHY you need your monitors mounted flush with the/a wall ?

kendale wrote:

Aloha, You could also sandwich another layer of 3/4 ply or MDF on the inside to help beef it up a bit :wink: Aloha 8)

After reading the information from Soundman, I think that I will most certainly be sandwiching another layer of 3/4" MDF for the added mass. I was even thinking of adding a layer of HardieBacker™ 500 cement board between the two. It has a thickness of 0.42" and weight of 2.6 lbs. psf (12.7 kg/m2) according to the manufacturer's website.

Ro wrote:

Have you asked yourself WHY you need your monitors mounted flush with the/a wall ?

It's not a need. It is more of a want. I have read of others and their satisfation with flush mounting monitors so I figured I would give it a try. I have seen it done with these particular KRK's and haven't come across any bad reviews so the question I posed to myself wasn't WHY but WHY NOT. :wink: Plus I simply think it looks better. 8) AR

One question about the design.. The glass door ? It will probably cost alot, just the glass, Couldn't you put another door from the Live room into the hallway ? and just putting in a window (without knowing, I'm pretty sure that isolating a window is easier that isolating a door.) Also, any toughts about how to get fresh air in and out of the room ?

Addni wrote:

One question about the design.. The glass door ? It will probably cost alot, just the glass, Couldn't you put another door from the Live room into the hallway ? and just putting in a window (without knowing, I'm pretty sure that isolating a window is easier that isolating a door.)

The glass doors will be sliding glass doors not glass doors on henges. I once considered putting a seperate entrance to the live room in the hallwaly area and using a window for a visual to the control room. I priced two pieces of glass 4' x 3', one 3/8" and the other 1/2" thick, and the glass alone was over $1000. :shock: I didn't even bother pricing the two additional doors that I would've also needed. I could purchase both sets of sliding glass doors for much less. :D It's a compromise of sorts. The sound isolation will be less between the two rooms but I believe that I can live with it. The sliding glass doors allow for a better visual between myself and the musician(s). They will also make it easier for me to access the live room for quick adjustments and changes in mic placement.

Also, any toughts about how to get fresh air in and out of the room ?

I have been doing a lot of thinking on this one lately. I am most likely going to tie back into the existing HVAC system. My current thinking is to bring air into the both rooms through their ceilings via some sort of silencers that I will construct. For the control room I am thinking of returning the air through the bottom of the center section of my soffit, into a cavity against the back wall, and out through another silencer in the ceiling. I haven't come with an air return idea for the live room yet but if you have any suggesetions feel free. :wink: -AR

It's been a while but I'm still ticking. Here are some updated design pics. So far so good ...I think :?: Any advice :?: -AR

Aloha, Any chance you could post your skp file, please? Thanks! :wink: Aloha 8)

No problem. Here's the almighty skp file - http://www.mediafire.com/?sharekey=20d2 ... f6e8ebb871 I hope it's manageable -AR

Aloha, Got it, thanks! Back in a few...:wink: Aloha 8)