You are looking at something like this which is far from cheap :
[[url=http://[/URL]="http://www.google.c…"]
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Any other solutions not including 4 walls will still allow spills and not helping much on not disturbing your friends.
Lowering the internal reverb of a room helps preventing build ups and so reduce a bit of spills but, it's far from being able to get unnoticed in the middle of the night ! ;)
If I was you, I'd try to control the sound of the room a bit to make the recording sound good and then negociate hours to do your thing...

I've always messed with the idea of a simple "outside in" style iso box/booth. Basically it's just 4 baffles made from 2x_ frames and a ceiling type panel. Some layers of drywall on one side, firetrested fanric/insulation on the other. I picture like four doors, as far as the way the thing hinges and latches together. I dunno I've never ever tried drawing it or making one. Your probably better off with one of those booths like Marco posted. They aren't cheap, but they're nice looking. I've never used one, but the site does have data up.

The thing I am consider is the common floor, your bedroom share with the rest of the house. Other than that a few small walls and a ceiling are fairly straightforward.

I had a Customer who improvised one him-self at home.. Thing is, it was resonating at 200hz and all his recording were having too much of that frequency... the recording he made in his living room sounded better.. ;)

I built one when I lived in an apartment complex and it was fantastic. I basically made four frames, a floating floor, and a framed ceiling with the proper acoustic insulation inside. And then I filled the inside with the egg-crate style treatment. The one thing is to make sure you're not placing your mic in a corner, or it's going to get real bassy.

Also, I built a shelf on the inside to place a laptop so I could control it. But upon second though, I wish I had built a shelf on the outside of the window and placed the laptop there, and just had a wireless mic on a small shelf inside.

" I basically made four frames, a floating floor, and a framed ceiling with the proper acoustic insulation inside. And then I filled the inside with the egg-crate style treatment."

You could have used a closet and gotten the same results without the material cost, the loss of time. Exactly what is proper acoustic insulation anyway?

s

Ledger Note, post: 429528, member: 49103 wrote: And then I filled the inside with the egg-crate style treatment. The one thing is to make sure you're not placing your mic in a corner, or it's going to get real bassy.

Your bassy corners are normal when using egg-crate style treatment like you say. 1 or 2 inches foams only absorb form about 800hz to 2khz they are not the ideal treatment. But I understand you can get away with it if you only do vocals...

Brien Holcombe, post: 431892, member: 48996 wrote: Exactly what is proper acoustic insulation anyway?

Proper in-wall isolation would be something like Roxul Safe and Sound : http://www.roxul.com/residential/create+a+quiet+home/which+safe+n+sound
Or other similar alternative from other brand. Surface treatment needs calculations or audio analyzation to to determin what needs to be corrected. Throwing anything on walls without knowing the defects of the room is like wearing a condom all night in a club while not knowing if you'll meat someone.. It may do more arm than help ;)

"Proper in-wall isolation would be something like Roxul Safe and Sound :"

Balony...any typical insulation will do the trick...All you are trying to do is damp the cavity created in the panels.

Btw...insulation and isolation are three different things.

Brien Holcombe, post: 431895, member: 48996 wrote: "Proper in-wall isolation would be something like Roxul Safe and Sound :"

Balony...any typical insulation will do the trick...All you are trying to do is damp the cavity created in the panels.

Btw...insulation and isolation are three different things.

Sorry for my french thong but 1 + 1 = 2, not three ;) just teasing.. thanks and sorry for the Typo !!
The french translation for insulation is isolation ! lol
So for us in french, protecting from heat transfer is isolation and form noise it's insonorisation... go figure..

Any typical insulation will do the trick ? not sure it's true. (not an expert of course...)
But if you put spray foam or styrofoam it won't do a good job for audio as with mineral wool. I chose Roxul because it's made specially with audio in mind in its composition but it's true any Wool will help !
[="http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&uact=8&ved=0CAcQjRxqFQoTCPalwf-FzMcCFUwSkgod6OsFww&url=http%3A%2F%2Fwww.ohiobasementauthority.com%2Fadditional-services%2Fspray-foam-insulation.html&ei=DnjgVfbmMsykyATo15eYDA&psig=AFQjCNGWlug9DxRncU9j37_NdYMzMtte0g&ust=1440860547698248"]
[/]="http://www.google.c…"]
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Brien Holcombe, post: 431892, member: 48996 wrote: " I basically made four frames, a floating floor, and a framed ceiling with the proper acoustic insulation inside. And then I filled the inside with the egg-crate style treatment."

You could have used a closet and gotten the same results without the material cost, the loss of time. Exactly what is proper acoustic insulation anyway?

Improper use of materials is discouraging. Proper placement and better design coulda gotten a nice little ISO booth that could handle a decent combo amp.

-EDIT-

My apology to brien holcombe, I meant to respond to the same part of Ledger Notes post, as he did.

Ledger Note said:

" I basically made four frames, a floating floor, and a framed ceiling with the proper acoustic insulation inside. And then I filled the inside with the egg-crate style treatment."

kmetal, post: 431899, member: 37533 wrote: Improper use of materials is discouraging. Proper placement and better design coulda gotten a nice little ISO booth that could handle a decent combo amp.

I did not say that...I quoted that...

Brien Holcombe did NOT say "" I basically made four frames, a floating floor, and a framed ceiling with the proper acoustic insulation inside. And then I filled the inside with the egg-crate style treatment."

Brien Holcombe quoted that comment..

pcrecord, post: 431894, member: 46460 wrote: s
Proper in-wall isolation would be something like Roxul Safe and Sound : http://www.roxul.com/residential/create+a+quiet+home/which+safe+n+sound
Or other similar alternative from other brand. Surface treatment needs calculations or audio analyzation to to determin what needs to be corrected. Throwing anything on walls without knowing the defects of the room is like wearing a condom all night in a club while not knowing if you'll meat someone.. It may do more arm than help ;)

I see the issue now...you are reading in French and trying to explain in English. Problem may be in several things, break down in communications and most likely a lack of understanding on your part. You express your concern for inner room treatments but what I am discussing is cavity insulation. I remember who you are now, you like to recommend that posters should test rooms that are too small to be of any use, much like this one. Anything less than 2500 cubic feet does not need testing we already know the issue, flutter and low frequency build up.

I would like to look closer at a few more things:

I said "Balony...any typical insulation will do the trick...All you are trying to do is damp the cavity created in the panels."

And then you said, after explaining that you were not an expert "Any typical insulation will do the trick ? not sure it's true. (not an expert of course...)
But if you put spray foam or styrofoam it won't do a good job for audio as with mineral wool. I chose Roxul because it's made specially with audio in mind in its composition but it's true any Wool will help !"

What is typical insulation? I have no idea how you made the leap to styrofoam or spray foam.

At some other point, after explaining that you were not an expert you also said "Or other similar alternative from other brand. "

Now exactly how does my comment of "typical insulation" not tie into "Or other similar alternative from other brand. " and HOW does it lead to styrofoam or spray foam?

And on a final note "Roxul because it's made specially with audio in mind"

More balony. Marketing might make you believe that it is true but typical paper faced or faceless insulation will yield the same results. Mass is what stops low frequency energy...not insulation.

Not finished yet: "Your bassy corners are normal when using egg-crate style treatment like you say. "

More balony. This is a direct by product of a small enclouser were bass /low frequency cannot get away fast enough due to the confinements of the enclouser and will build up in the corners anyway as a means of accumulation in search of a natural means of egress.

I could say that spray foam and styrofoam are kinds of insulations but work differently as wool, so saying any will do is not accurate depending on your goal. But I might have fail to interpret your meaning of typical
I could say that Roxul adds mass to their wool that adds to their effectiveness but you could be right and this is just gimmicks
I may not know anything about tight spaces even if I work in my 11'x10' booth everyday with acoustic drums electric and acoustic guitars..
I may be french fellow that don't get all english nuances and between the lines messages.
But I kind of get that you systematicly want to say I'm wrong on everything I say (maybe I am) without giving detailed info to help me understand my errors
Honestly I'm sad we got to this wrong direction together, my thong got me in argument only twice in thousands of messages here.

I have no pretention about anything, I'm just a pationate recordist who tries to learn and share thoughts about the craft. I'm happy to be corrected if I'm wrong and I'm very greatfull to many members who participated in making me better at what I do.
I'm not here to confront or prove anything so I hope we can step back from this and start on a new positive collaboration ;)

BTW I never wrote anything close to this:

Brien Holcombe, post: 431907, member: 48996 wrote: I remember who you are now, you like to recommend that posters should test rooms that are too small to be of any use, much like this one. Anything less than 2500 cubic feet does not need testing we already know the issue, flutter and low frequency build up.

The issue is this. You read this line "Exactly what is proper acoustic insulation anyway?" and thought it applied to you in that I was looking for an answer. I wasn't looking for an answer I was trying to get whoever posted that to explain the rationale behind it.

Now here we are.

"But I kind of get that you systematicly want to say I'm wrong on everything I say (maybe I am) without giving detailed info to help me understand my errors"

Nope, what you are incorrect on is the belief that Safe and Sound is somehow better because Roxul says it is. You present no data to support your claim but you suggest that I should support mine.

Roxul is more expensive, nuf said. Materials like Roxuls safe and sound or Owens Cornings QuietZone are simply marketing to an audience. These types of insulation have better ability at not catching fire and may get you a point on the STC scale, might get higher in one frequency and lower in another in respect to Transmission Loss but overall typical residential pink fluffy insulation out performs for an acoustic type assembly.

Any claim that somehow safe and sound is by far the better of insulation to use in the cavity of a wall can be disputed by the following articles:
http://archive.nrc-cnrc.gc.ca/obj/irc/doc/pubs/ir/ir693/ir693.pdf
http://archive.nrc-cnrc.gc.ca/obj/irc/doc/pubs/ir/ir761/ir761.pdf

"Insulation will lower the resonance frequency, and most of the reason that i always recommend low-density common building fiberglass for insulation is that it seems to be the most effective insulation type at lowering resonance. Other types are better absorbers, but the boring common stuff is best at lowering resonance."
(Except from a post by Brian Ravnaas, developor of [="https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0CCUQFjABahUKEwiHxqj9vM3HAhVC7R4KHaWWBJ4&url=http%3A%2F%2Fwww.greengluecompany.com%2Fabout%2Fhistorygroup&ei=7TfhVcebOMLae6WtkvAJ&usg=AFQjCNHs23RDShM4xhd6YbXCUgg5nyr9UQ&sig2=zNZgQcmDEagCpYBF6cytBA"]Green Glue[/]="https://www.google…"]Green Glue[/]: [[url=http://="http://www.avsforum…"]post #101 of 120[/]="http://www.avsforum…"]post #101 of 120[/] from
( this Link: http://www.avsforum.com/forum/19-dedicated-theater-design-construction/452667-just-how-crazy-idea-ceiling-sound-reduction.html which should be recommended reading.)

Rod recommends it as well.

I just like saying "enregistreur multipiste" and "bande magnétique".

I can't acces those :

Brien Holcombe, post: 431910, member: 48996 wrote: http://archive.nrc-cnrc.gc.ca/obj/irc/doc/pubs/ir/ir693/ir693.pdf
http://archive.nrc-cnrc.gc.ca/obj/irc/doc/pubs/ir/ir761/ir761.pdf

I've done some research and I have a hard time finding accurate STC rating to compare Roxul Safe and sound and OwensCorning EcoTouch or Quietzone.
I installed my Roxul, it was easy and it does the job that I expected. It was about 5$ more a bag from other products and bought 10.
I might have been ripped off but just the easyness of installation is a keeper for me. I'm not gonna cry over 50$.
But if I need to build another studio in the future I will keep our discussion in mind and seriously consider OwensCorning.
Thanks !

I think I paid around $40 per 15.25" x 47" bundle of Roxul S&S last year... it was at either Loews or Home Depot. I didn't find it "difficult" to install, in that it was easy to cut, work with and shape, but I was an idiot and picked one of the most humid days of the year to install it, so it was clingy. I was smart enough to have worn a mask, but I was pretty itchy for a few hours.

I had a much easier time in finding Roxul at local DIY stores than I did finding any OC Rigid products. The OC Rigid that I used, I already had. IIRC, had I needed more, I would have had to have ordered it online. There was one place that carried it locally, but they required a contractor's license in order to purchase materials from their company.