John Sayers' Recording Studio Design Forum Archive

Hi guys,

I'm a complete newb and I'm planning to build a bass guitar practice room for my partner inside the living room. Any information you can provide to help me find answers to my questions below and avoid expensive and annoying mistakes will be highly appreciated.

The living room has a funny bit around the corner in North East which I would use. A true to scale drawing is attached (only the gaps between the existing walls and the planned studio walls are exaggerated to show on the drawing).

I've been good and read the Home Recording Studio by Rod Gervais, some of the info on this site and others. The room would be plasterboard walls and ceiling and concrete floor, a double wall design that only connect to each other at the door jambs. Two layers of plasterboard on each side and acoustic batts on the inside of each. It's all on the ground floor and concrete slab. The lengths of the walls are currently planned as 1900, 2060, 2100, 3150mm and 1900mm high (6'3", 6'9", 6'11", 10'4" and 6'3" high), that's as measured inside the studio. It would have two windows, one in the North wall and one in the West wall.

She would not be playing very loud in there as we're health conscious. We just need the room to improve the quality of my own life and that of our neighbours. Recording is not the idea at this stage and I'm not sure if it's even possible given the acoustics of such a room.

The budget would be as low as possible, such as around AUD 2000 (USD 1500). That means recycled timber, great deals on plasterboard etc.

My questions are:

1) In a room with such measurements, is it possible to achieve any sort of acceptable sound quality for practicing bass and what would it take? Since recording is not on the agenda, some of the bad acoustics can hopefully be EQ-d out.
2) Would recording ever be possible there and what would that take?
3) Should I consider maybe changing the dimensions of the studio given I have some floor space I could sacrifice in the living room? I don't really want to but if there's big gains from that, I might.
4) Should the layers of plasterboard in the walls be glued together? If yes, would maybe screws be enough to hold them together (I'm thinking of being able to take it all apart and reusing it if I ever had to.)
5) In his book Rod suggests making a window of two separate sheets of thick glass. I was left with the impression that the thicker one is on the inside of the studio. Is that correct?
6) The thickest glass I could find was 19mm (3/4") and very expensive. Two sheets of 10mm would be much cheaper. Since glass sheets tend to form something of a vacuum between them, could I just put two 10mm sheets together and silicone around the edges to avoid air or moisture getting in between them? I would love to avoid self laminating as I'm afraid the resins would go yellow or something over time.
7) For sound absorption, would acoustic batts made of polyester/PET on the walls work for high to mid frequencies? I have a problem with glass wool (fiberglass) (and rock wool) 'cause of health concerns. I know many believe they're safe but I personally don't want to touch them. Unless covered by an airtight membrane, which brings the next question.
8 ) Would something like this be effective in my case Limp Mass Absorbers ?

Thank you so much for your time! I understand you get nothing in return but gratitude.

Wow ! Not sure how I missed this for so long, but I only just found it. Hope it's not too late!

1) In a room with such measurements, is it possible to achieve any sort of acceptable sound quality for practicing bass and what would it take?

It's not ideal, but it is workable, yes. The biggest issue is the very low ceiling. 190 cm is loooowwwww! I would suggest taking a look at how to improve that. Have you considered doing the ceiling "inside-out"?

2) Would recording ever be possible there and what would that take?

It's worth trying, for sure. When I track bass in questionable locations, I usually take several tracks: one with a DI box, direct form the instrument, one with a mic right up against the speaker, one mic a bit further away, and one far away, at the other end of the room, to pick up some "ambiance" from the room itself. I then time-align them in the DAW, and fiddle around with EQ and levels, and maybe some reverb, until I get what I'm looking for. Often, it's mostly the second mic that has the best sound, with a little room sound, and just a touch of the DI (if any).

3) Should I consider maybe changing the dimensions of the studio given I have some floor space I could sacrifice in the living room? I don't really want to but if there's big gains from that, I might.

In general, "the bigger, the better". Most instruments can benefit from more air volume in the room. You can do a test for yourself, to see if the extra length would be worthwhile: set up the bass amp in various rooms in the house that have sizes similar to what you are considering, and see how it sounds in each. I think you'll find that it sounds lousy in the small rooms, and increasingly better in the larger rooms....

4) Should the layers of plasterboard in the walls be glued together?

Definitely not! Nope. Bad idea. What you CAN do is to use something called "Green Glue" between them... despite the name, it is not actually glue. It is a special acoustic product, that acts as a constrained layer damping compound in between the layers, and can greatly improve low frequency isolation. There are no substitutes, and it is not cheap, but it's worthwhile if you can afford it.

would maybe screws be enough to hold them together (I'm thinking of being able to take it all apart and reusing it if I ever had to.)

Check your local building code, but I think you'll find that screws are allowable for attaching drywall. They usually are. Use standard drywall screws on the first layer, and screws that are 5/8" longer on the second layer.

5) In his book Rod suggests making a window of two separate sheets of thick glass. I was left with the impression that the thicker one is on the inside of the studio. Is that correct?

You are doing a single-leaf wall (or you should be!), so your window will be a single pane window that is set up opposite the existing single-pain window in your outer leaf. So no, you only need one pane there, just like you only need one leaf for the actual studio (even though the leaf is made from two layers of drywall with Green Glue between, that is still consider to be one single leaf). The glass should be the correct thickness such that the surface density of the surface density of the glass is the same as the surface density of the leaf itself, or a little higher.

6) The thickest glass I could find was 19mm (3/4") and very expensive.

Not necessary. The density of drywall is roughly 680 kg/m3. The density of glass is roughly 2500 kg/m3. That's around 3 times as high, so your glass should be about one third the thickness of your leaf. If your leaf is two layers of 5/8" drywall, that's 1.25", so your glass could be around 7/16", and that would be fine.

7) For sound absorption, would acoustic batts made of polyester/PET on the walls work for high to mid frequencies?

If you have the acoustic data sheets for the product you are thinking of, it's worth looking at. But for a small room like that, you won't need much absorption in the highs. Rather, you will need a large amount of absorption in the lows! Small rooms always need major bass trapping.

I have a problem with glass wool (fiberglass) (and rock wool) 'cause of health concerns.

Not sure if you have read this, but you might want to: http://www.gearslutz.com/board/bass-tra ... eview.html

Would something like this be effective in my case

Perhaps, if you can tune them correctly, and place then correctly, but for DIY studios it is far, far easier, and much more effective to use simple broad-band porous absorption.


- Stuart -