[Alwayswantmore]

My previous plan for a slab house have been dropped, and I and now building on a basement lot. The unfinished basement is huge!!!, with 9' from concrete floor to the bottom of rafters.

I've been looking at ideal dimensions, but focused now on in few of the finer points... BTW: Strictly interested in stereo, not HT.

1.) Would it be an advantage to go with a slightly raised strand-wood floor (the raised floor could be covered by area rugs or carpet), to improve the "feel of the subwoofer"? Or am I better off with carpet over the cement floor?

2.) Should I go dropped-panel ceiling or drywall?

I plan to center the listening room away from the concrete walls, plus the concrete walls already have 2.5 inch layer of solid foam insulation over precast concrete. The wall to the back yard is studs (ie. no concrete).

3.) Would there be any advantage to incorporate one of the concrete walls into the room? Maybe for the front wall (the precast concrete walls are designed so you can finish with drywall, and fill the cavity behind the with insulation.

4.) For the side walls in the listening room, could I get by with a single layer of drywall (facing into the listening room), -- and to save money -- not put drywall on the "back side" of the studs? Due to the size of the basement, the listening room side-walls will be out a minimum of 12 feet from the concrete walls.

5.) I have enough room to fit a slightly modified version of Carda's Golden Golden Trapagon >>>  http://www.cardas.com/content.php?area=insights&content_id=41&pagestring=Listening+Room+Dimensions
 
[see bottom of page] I can fit the top view, but would need to limit the ceiling height in the back of the room. Any thoughts on this design?

Thanks, Kent

[Ethan Winer]

Kent,

Would it be an advantage to go with a slightly raised strand-wood floor (the raised floor could be covered by area rugs or carpet), to improve the "feel of the subwoofer"? Or am I better off with carpet over the cement floor?

I'd leave it carpet on concrete. If a slightly raised floor is a little better - and I'm not sure it is - the improvement won't be enough to warrant the extra cost. Better to put that money into other things.

Should I go dropped-panel ceiling or drywall?

How important is isolation to the upstairs? If you don't need isolation, don't sheet rock the ceiling. Construction that increases isolation generally makes the bass response inside the room worse.

Would there be any advantage to incorporate one of the concrete walls into the room?

No. If a wall is concrete, plan to build a separate sheet rock wall at least six inches inside, and stuff the cavity with fluffy fiberglass.

I have enough room to fit a slightly modified version of Carda's Golden Golden Trapagon

I'm not impressed with most of those dimensions. You can make your room longer than 20 feet, yes? Bigger is generally better.

--Ethan

[brj]

Would it be an advantage to go with a slightly raised strand-wood floor (the raised floor could be covered by area rugs or carpet), to improve the "feel of the subwoofer"? Or am I better off with carpet over the cement floor?

I'd leave it carpet on concrete. If a slightly raised floor is a little better - and I'm not sure it is - the improvement won't be enough to warrant the extra cost. Better to put that money into other things.

Acoustics aside, make sure that you address moisture control as part of the finishing process.  I don't know what part of the world you live in, but I've heard more than one story about carpet on concrete trapping moisture and causing problems.  Depending on where you are, the solution might be as simple as a vapor barrier, but it might also require much more.  The walls might need to be addressed as well, depending on the surrounding grade, soil type and local rainfall.

[bpape]

If you want both mosture protection on the floor and a bit of 'feel', there is a product called Dri-Cor that is sold at Home Depot.  It does an excellent job and leaves only a very small cavity below so resonances are not an issue.  You can build your walls on top of it for isolation.

Speaking of isolation, it's not only to keep sound from getting into the rest of the house - it's also for keeping sounds from getting into your room and raising your ambient sound floor.  A quiet room allows you to much better hear the details in the music.  There are many ways of dealing with isolation without causing room issues inside.

Bryan

[Alwayswantmore]

Thanks Ethan, Bryan and brj,

I don't need the basement for living space, so my plan is to build a listening room within the larger unfinished space (floorplan below). The basement is full walkout and warranted as watertight. [I will however need to address humidity levels in the unfinished portion, and general HVAC in the listening room.] The picture at the bottom shows the general construction techniques. Again, the rafters are 9', and I can get HVAC and lighting access via side walls, so all of the vertical space can be dedicated to the room.

As far as isolation from the upper floor, yes that would be an advantage (at least to support reasonable listening levels). I also assume I will need absorption panels for point of first reflection and maybe bass traps in corners.

Bryan, to your point on isolation: Much of the basement is underground and the back wall faces a natural area buffer, so there will be no noise from neighbors or cars. HVAC for the main floor will be in the attic -- and the compressor for the main floor is outside, on the same level as main floor. So this room should be very quite. [HVAC and/or a humidifier should be the only source of noise in this area -- which I can turn off for critical listening sessions.]

My best bet might be to build-out the middle section of the unfinished basement, taking advantage of the existing framed walls. This space could be a maximum of 18'2" wide and up to 24'6" feet deep. There would be a door at one end, and -- if I use the maximum length -- windows on the other end. I could always add in a new wall to change one of the dimensions or close off the windows. Under this plan, I would probably default to the dimension ratios described on Ethan's’s web site.

The carpet will be a medium-grade of plush, with a better than average pad (I don’t have exact specs at my fingertips).

[See pictures below for more detail.]

Questions:
1.) Is it OK to go with drywall on only one side of the studs (to save money -- and possibly allow more bass to escape the listening room)?
2.) Are acoustical panel ceilings better than drywall?
3.) Any other suggestions?

Thanks again. Kent

[woodsyi]

I don't like the way the windows are going to be on the front wall behind the speakers or the door if you flip it.  Can you use the room on the side that looks more like 20' x 30'? It' would also be away from pipes on the bathroom (yes you can hear water going through pipes).  If I had my way from scratch, I would design and build diffusion into the rear and side walls.  I would drop the ceiling and employ acoustic tiles.  I would also employ bass trapping in the corners above the ceiling.  I would do the same on every corner if I had false walls with cavity behind.  I would raise the floor not only for acoustic reasons but for water issues (just in case) as well.  At the same time, I would fill in an area with concrete where you can spike your equipment rack to.  You will obviously get dedicated power outlets but remember to also put wired network connections for future use -- sometimes wired is still better than wireless.  I would put in zero surge surge protection on the lines if you live in area with prevalent power problems. 

Just my 2 cents and I envy your situation where you have a free run at building a room.  Good luck.

[bpape]

Water running, people walking, dishwashers, washing machines, duct noise, etc.  Those are the kinds of sounds that will infiltrate the room.

If you're going to do a tile ceiling, I'd do a wood floor (finished) and plan for a nice rug between you and the speakers.  Having a carpeted floor AND a tile ceiling is a ton of high frequency only absorbtion.  Add in reflection point coverage and general decay time control and IMO the room will be too dead in the highs. 

Don't kill yourself trying to get perfect room dimensions - there aren't any.  All you try to do is avoid particularly bad combinations.  More room volume is always a plus.  I'll take a larger room with slightly less 'perfect' ratios any day.  It gives you a ton more options and flexibility for speaker placement and seating placement which can make a huge difference in perceived frequency balance.

Bryan

[Alwayswantmore]

I don't like the way the windows are going to be on the front wall behind the speakers or the door if you flip it. 

I can always place a wall in front of the windows.

Can you use the room on the side that looks more like 20' x 30'? It' would also be away from pipes on the bathroom (yes you can hear water going through pipes). 

I could use this room, but it presents a few drawbacks:

1.)There would be two cement walls to deal with.

2.) I would need to construct a walk way from one of the doors to give it a finished appearance.

3.) As far as the pipes, the basement bathroom is simply stubbed for future buildout. All existing pipes will be in the rafters. With only two of us in the house, most of the time water will not be running.

If I had my way from scratch, I would design and build diffusion into the rear and side walls.  I would drop the ceiling and employ acoustic tiles.  I would also employ bass trapping in the corners above the ceiling.  I would do the same on every corner if I had false walls with cavity behind. 

All in all this would likely cost quite a bit more than option 1. I also thought that option 1 would put the cement walls at a significant distance from the listening walls, which I thought would be an advantage????

At the same time, I would fill in an area with concrete where you can spike your equipment rack to. 

Great idea!!

I would put in zero surge surge protection on the lines if you live in area with prevalent power problems. 

What is this?

Thanks for the input. Kent

[Alwayswantmore]

Please keep your comments coming. Not to sound defensive, but cost is also a factor. So here is some of my rational for option 1. If I'm wrong, please set me straight.

Water running, people walking, dishwashers, washing machines, duct noise, etc.  Those are the kinds of sounds that will infiltrate the room.

We are renting a house with the same construction. Ducking for the main floor comes from the attic and ceiling, so really the basement is very quite.

If you're going to do a tile ceiling, I'd do a wood floor (finished) and plan for a nice rug between you and the speakers.  Having a carpeted floor AND a tile ceiling is a ton of high frequency only absorption.  Add in reflection point coverage and general decay time control and IMO the room will be too dead in the highs.

I will already have the carpet at no charge, so I'd like to use it (we are ripping out carpet from the main floor to replace with hardwoods). So to keep costs down, if it's not too bad, I could go carpet on floor and drywall on ceiling.

Basically if I finish off the drywall on option 1, use my existing carpet, add some basic electrical and needed HVAC, I should be able to get by for pretty cheap. I could even do the drywall myself to save $. Adding a wall in front of the windows would be pretty cheap too.

So more bucks for big differences are worth considering. Marginal difference probably not worth it to me. And I can always use room treatments to help balance out the room (assuming it has no fatal flaws that can't be overcome).

Any recommendation for ceiling height?

[bpape]

Please keep your comments coming. Not to sound defensive, but cost is also a factor. So here is some of my rational for option 1. If I'm wrong, please set me straight.

Water running, people walking, dishwashers, washing machines, duct noise, etc.  Those are the kinds of sounds that will infiltrate the room.

We are renting a house with the same construction. Ducking for the main floor comes from the attic and ceiling, so really the basement is very quite.

If you're going to do a tile ceiling, I'd do a wood floor (finished) and plan for a nice rug between you and the speakers.  Having a carpeted floor AND a tile ceiling is a ton of high frequency only absorption.  Add in reflection point coverage and general decay time control and IMO the room will be too dead in the highs.

I will already have the carpet at no charge, so I'd like to use it (we are ripping out carpet from the main floor to replace with hardwoods). So to keep costs down, if it's not too bad, I could go carpet on floor and drywall on ceiling.

Basically if I finish off the drywall on option 1, use my existing carpet, add some basic electrical and needed HVAC, I should be able to get by for pretty cheap. I could even do the drywall myself to save $. Adding a wall in front of the windows would be pretty cheap too.

So more bucks for big differences are worth considering. Marginal difference probably not worth it to me. And I can always use room treatments to help balance out the room (assuming it has no fatal flaws that can't be overcome).

Any recommendation for ceiling height?

Carpet floor and drywall ceiling will be fine.  As for ceiling height, as high as you can get it.

Bryan

[Alwayswantmore]

Please keep your comments coming. Not to sound defensive, but cost is also a factor. So here is some of my rational for option 1. If I'm wrong, please set me straight.

Water running, people walking, dishwashers, washing machines, duct noise, etc.  Those are the kinds of sounds that will infiltrate the room.

We are renting a house with the same construction. Ducking for the main floor comes from the attic and ceiling, so really the basement is very quite.

If you're going to do a tile ceiling, I'd do a wood floor (finished) and plan for a nice rug between you and the speakers.  Having a carpeted floor AND a tile ceiling is a ton of high frequency only absorption.  Add in reflection point coverage and general decay time control and IMO the room will be too dead in the highs.

I will already have the carpet at no charge, so I'd like to use it (we are ripping out carpet from the main floor to replace with hardwoods). So to keep costs down, if it's not too bad, I could go carpet on floor and drywall on ceiling.

Basically if I finish off the drywall on option 1, use my existing carpet, add some basic electrical and needed HVAC, I should be able to get by for pretty cheap. I could even do the drywall myself to save $. Adding a wall in front of the windows would be pretty cheap too.

So more bucks for big differences are worth considering. Marginal difference probably not worth it to me. And I can always use room treatments to help balance out the room (assuming it has no fatal flaws that can't be overcome).

Any recommendation for ceiling height?

Carpet floor and drywall ceiling will be fine.  As for ceiling height, as high as you can get it.

Bryan

Thanks again Bryan. From a sonic perspective, is there any advantage to put drywall on the back side of the studs? Or can I get by with a single layer of drywall facing into the listening room?

[bpape]

From an inside the room perspective, you're actually better not to put drywall on the back side.  Fill the stud cavities with insulation though. 

Now, from an isolation standpoint, it's better to do double on the inside and nothing outside.  Next best is single on both sides.  Double on the inside will drop the resonant frequency of the wall - but it also becomes a less efficient absorber in the upper bass (100-150Hz ish) so more bass control in the room is required.

It's never a simple answer, is it.   

[woodsyi]

Here is the link to a panel unit that I used, PM20-240.  http://www.zerosurge.com/PDF/PM20_120b.pdf

[Alwayswantmore]

woodsyi, thanks for the panel info. Bryan, thanks, I'm getting a pretty good idea of where I could go on a limited budget. Should be a fun project!

[Fhilip]

I accede that the afterward are kinds of sounds that will access the room. Water running, humans walking, dishwashers, abrasion machines, aqueduct noise, etc.


_________________
Thermostat

[JLM]

Just found this thread.

I built an audio only basement listening room 4 years ago:

I strictly followed the Cardias formulas for a rectangular room and speaker/listening position lay out, while trying to make the room as big as possible.  It ended up being 8 ft high by 13 ft wide and 22 ft long.

All interior walls used insulated double staggered stud walls with drywall, so only the top and bottom plates go all the way through the wall cavity.

Because this was part of a new build, most of the room?s features cost me nothing.  So wall insulation, 12 gauge wiring, whole house surge protector, insulation under the concrete slab, and insulated flexible ductwork for the ventilation (which works great) were freebies.  More freebies included three separate 20 amp circuits for the audio system that were grounded together and our own underground electrical service with our own transformer.  The home also has all new appliances.

I used an insulated fiberglass exterior door (with weather stripping) which works great.

My only splurge was cryo?d hospital grade electrical receptacles (about $100). 

My only downfall was the ceiling as the builder did not install the ceiling drywall with gauge metal ?Z? channels as I?d specified.  Between that and the six recessed cans I hear the washing machine, dryer, vacuum, footsteps, etc. from above.  (But without those, the room is ?spooky? quiet.)

I?ve added GIK panels, but between the room, setup, and 8 inch single driver speakers, there is very little room interaction so the panels frankly don?t do much for me.

Bottom line, having your own room will be fantastic.  Getting it to sound great doesn?t require much more than good planning up front and shouldn?t cost a whole lot.

Keep us posted!

[Red Dragon Audio]

http://www.kineticsnoise.com/

Their ISOMAX system in conjunction with proper sound isolation techniques is extremely effective at isolating a listening room.  This system is cost effective and only takes up 1.5" of space in your room (great for walls and ceilings).