Built-in bass traps?

[Tadpui]

We finally started construction on my basement finish, part of which is a dedicated 17' x 14' x 8' studio. We were going over the finer details of the finish, and one of the corners of what will be a double wall has some drain pipes in it. So the contractor suggested just cutting the corner at an angle and fitting Roxul in the void rather than make a soffit. Basically it would be a bass trap in the corner behind a couple of layers of drywall. So we thought heck, why not do that to all 4 corners of the room?

Would this be as effective at low-frequency attenuation as a regular DIY corner bass trap? I'm not exactly sure what the 2 layers of drywall would to to its effectiveness other than override its "broadband" characteristics. Would it still be a good low-frequency trap?

 

[BroKen_H]

Well, maybe you could reduce the impact by using Acousti-Board or similar over the corners...helps the sheetrock STC.

 

[Tadpui]

Interesting, thanks for the suggestion. We're using green glue between the 2 layers of drywall throughout the studio space, and I'll clarify with him today that both sides of the double wall should use that same design (only one double wall: the other 3 sides of the room are concrete foundation). So hopefully the STL/STC of the walls will be sufficient. I'm just wondering if a layer of this type of wall will defeat any of the lo-freq benefits of corner traps behind them.

If it's ok from an acoustic perspective, I'm ok with the kind of funky-looking result of an octagonal room. These "straddled" corners will be about the same size as a Roxul and fabric corner trap. But whoever ends up in this house after us will wonder what the hell this room was used for

 

[BroKen_H]

At least your not installing red lights and a 4x4 with a brass ring in the center of the room...friend of mine bought a house and found that room behind a secret door in the MB closet

 

[BroKen_H]

BTW, congrats on the new room. Hope you have as much fun as I did putting it all together. Got any budget for new gear?

 

[Tadpui]

At least your not installing red lights and a 4x4 with a brass ring in the center of the room...friend of mine bought a house and found that room behind a secret door in the MB closet

Whaaa??? What the hell would that have been for? And in a secret room, no less! That's awesome, and terrifying!

BTW, congrats on the new room. Hope you have as much fun as I did putting it all together. Got any budget for new gear?

Other than a new desk, I'm mostly set on gear for the time being (yeah, right, that feeling always lasts!). Once the room is complete, I'll set to work building broadband absorbers for the walls and ceiling, which will keep me busy for a while. And once that's done, I'll see how my existing gear works/sounds in the new space. I've been upgrading gear A LOT in the last year (new LDC mic, new interface, new monitors, new computer, new plugins, new bass, new Telecaster), so I get a sideways look from my wife every time I get excited about new gear. We just got married in February so I'm still feeling out how long my leash is

 

[mjbphotos]

I would think your corner plan wold work and make them low-end only absorbers (but would defer to John Brandt or Ethan's opinions, of course) but wonder WHY you would only want bass trapping there and not broadband? Also what if you ever need access to those drain pipes - is there access from the other side?

 

[Tadpui]

I would think your corner plan wold work and make them low-end only absorbers (but would defer to John Brandt or Ethan's opinions, of course) but wonder WHY you would only want bass trapping there and not broadband? Also what if you ever need access to those drain pipes - is there access from the other side?

I would add some mid and hi freq absorbtion and/or diffusion to the finished surface most likely, I have a feeling that a room this small will still need plenty of that as well. The main motivation is that it's one less thing that my clumsy hands will have to craft! I can focus on making 2x4 broadband absorbers for the walls/ceiling.

 

[mjbphotos]

Or you could just have the corner squared off, then build the corner trap/superchunk in front of the drain pipes, and have full broadband abosorption - either way, you're going to build something to handle the high end trapping, too.

 

[Tadpui]

Or you could just have the corner squared off, then build the corner trap/superchunk in front of the drain pipes, and have full broadband abosorption - either way, you're going to build something to handle the high end trapping, too.

Right you are! I might end up just using 2x4 broadband absorbers in front of the cut corners anyways. Or who knows, maybe acoustical foam since the lows will be handled there. I guess I'll cross that bridge when I get to it.

 

[RecordingMaster]

We finally started construction on my basement finish, part of which is a dedicated 17' x 14' x 8' studio. We were going over the finer details of the finish, and one of the corners of what will be a double wall has some drain pipes in it. So the contractor suggested just cutting the corner at an angle and fitting Roxul in the void rather than make a soffit. Basically it would be a bass trap in the corner behind a couple of layers of drywall. So we thought heck, why not do that to all 4 corners of the room?

Would this be as effective at low-frequency attenuation as a regular DIY corner bass trap? I'm not exactly sure what the 2 layers of drywall would to to its effectiveness other than override its "broadband" characteristics. Would it still be a good low-frequency trap?

Having the bass trap material behind drywall would make it a membrane which are usually built to absorb one very narrow band of frequencies based on your calculations and what you want to fix, etc. I'm no acoustician but I`ve made some superchunks myself and recenty finished rebuilding my room from the studs and considered that route as well. So long story short, from my reserach thatKs probably not your best bet. Better off having the superchunks on the room-side of the drywall vs behind it.

 

[JimmyS1969]

+1 ^^^

You will likely be best with a breathable cover for the corner traps. No drywall in front of them.

 

[Tadpui]

Cool, thanks for the advice fellas! I'll talk it over with the contractor tomorrow and tell him to just do normal corners (except for the one with the pipes in it that'll have to be cut somehow).