The No.1 Website for Pro Audio
need some advice on a making a Guitar Amp Iso booth
Old 21st January 2007
  #1
Here for the gear
 

need some advice on a making a Guitar Amp Iso booth

I am a new member to the board. But I cant lie I have been reading many of the threads from time to time for the past year.

I recently built a pretty nice size recording studio (1200 square feet) 4 rooms...lounge, control room, small live/rehearsal room (16x16x8) and large live room (20x25x34) in a warehouse. The other business within the warehouse only operates until 5pm....which nice because i then have until 8 in the morning to make as much obnoxiously loud noise as possible. I tried using the small live room as space to record guitars and bass during the day but I got a few complaints from the other employees. I cant blame them I like to crank my amps extremely loud to get my tone and basically I wont compromise....so for this months record I put myself and the band on a night schedule. But I'll be honest I'd really like to record guitars at anytime of day. I dont mind being a night owl to track drums........but I'd like to do everything else on my own schedule.

Any suggestions on a relatively inexpensive way to build a small guitar Iso booth.....just something to fit a 4x12 and or an ampeg 8x10?

Basically the offices are about 25 feet away from where I am planning to build the iso booth.....so i want it to be pretty dead to the world.

Any suggestions would be greatly appreciated.

-rob
Old 21st January 2007
  #2
This is what I would do...depending on where you are this shouldn't cost more than 500.00 to build. Maybe.

They key to isolating anything from the pussies who can't handle it is MASS/AIR/MASS . If I were you, depending on your situation, I would build a free standing room, off the exsisting floor. Keeping room for your mic stands and all, a room about 8x8 would be perfect and incredibly easy to build.

Start with an 8x8 floor. Make it just like you would see any other floor made...with 2x4s on their side as your floor joist. Float that floor frame on neoprene rubber to isolate it from the studio floor. Stuff the frame full of any insulation then put 7/16ths OSB over the top, then 5/8ths sheetrock, then sheetblock (auralex) then 3/4 OSB floor board. There's your floor! Solid and there aint no sound getting through that thing. Mass is key and be sure to seal every crack in the wood or sheetrock with caulk. make that puppy tight!

Next build your walls! 2x4 construction is fine as well. Once the fram is up, sheet rock the inside with one layer of 1/2" then another layer of 5/8" then another layer of 1/2". Yes three layers. Be sure to seal it tight on all layers! Do the same for your ceilings. Aside from adding tie lines and electrical, your inside should be done!

Next, get some type of resilient channel or even some thin strips of wood (maybe 1x2's) and stripe the outside of the room with them. These will help de-couple your outside layers of sheetrock from the islolation room. Once those are up and the walls and ceiling are insulated, tack on another layer of 1/2" and 5/8" of sheetrock to the outside of the room. This is essentially your MASS/AIR/MASS construction.

Now for your door...Get two solid core doors from your local hardware store along with some more 1x2s. Screw the two doors together using the 1x2s and insulation to separate the two...MASS/AIR/MASS! This door will end up being close to 4 inches thick once it is done. Get some heavy ass door hinges and your rockin! Make a neoprene seal around your door stops to help seal it when closed.

Thats what I did and it works puuurrrrfect. You can barely hear it outside the room much less 25 feet away and in the other room! Then again....you could just go pick up a power brake from Weber Speakers!

Hope this helps....I know its very general, but, if you would like some guidence, don't be afraid to PM me. All the best.

M
Old 22nd January 2007
  #3
Here for the gear
 

sweet!!

thanks soo much for the advice sounds really doable and fairly inexpensive and easy.

what do you think about concrete? Since I posted I just came into a bunch of free concrete blocks. What do you think about using them and maybe filling the cavities with sand? I know it sounds like a lot more work but since the material is free..its awfully enticing. The ceiling would have to still be sheet rock...I dunno just brainstorming.

What is a weber power brake?

thanks again...I really really appreciate it.... looking forward to ditching the night schedule and maybe getting back some sort of social life

rob
Old 23rd January 2007
  #4
Hey Rob. I can't advise you on the concrete thing. All I know is the key to isolation is MASS/AIR/MASS. With the concrete block, filled with sand, you are essentially creating a big solid mass. Only one mass. Although it sounds like a good idea, I think it would hurt more than help. Do it the way it is proven so your not kicking yourself in the ass later!

I can't remember what the actual model on the Weber was, but, its an attenuator built to go inline between your amp head and the speaker cab. It allows you to crank the hell out of your amp without blowing your ears out. But, then again, the speakers getting kicked around by your amp is half the sound. Just a thought really. Best of luck.

M
Old 23rd January 2007
  #5


Cinder blocks work well. Don't forget the ceiling and make sure you mortar the block wall well.

The bass cabinet will probably sound like ass in an 8x8 room.

The other things you can do are:

Get a 15w combo amp - record the bass DI - record a DI track on the Guitar and re-amp it later in the evening - rent an old convinience store or gas station so you don't have neighbors




-tINY

Old 23rd January 2007
  #6
Here for the gear
 

.

I'll save the concrete for another project. I am going with your plans. Thanks again..I'll let you know how it works........or doesnt

I tried a hotplate attenuator in the past....loved it on stage....but you're right...half the tone is pushing my greenbacks

-r
Old 23rd January 2007
  #7
Gear Head
 

The seal is important, too. You can't have any air gaps.

I'm not sure that double-door will work. Think it through before constructing.

Or did I not understand something?
Old 23rd January 2007
  #8
Gear Maniac
 
Scott R. Foster's Avatar
 

I have a THD amp with a power attenuator, and it works, but tone suffers at large settings. These may be a more practical solution as they simply allow you to run at lower power

http://www.thdelectronics.com/produc...low_jacket.htm

or buy / build an iso box versus a tiny iso room?

http://www.amptone.com/g101.htm

http://www.amptone.com/demeterssc1.htm

http://www.sweetwater.com/store/detail/IsolationCab/

If you build a box, it could be quite large to allow the use of a 4x12 cab [you will probably need some intense EQ regardless of box versus very small room - as mentioned above your bass cab will probably sound like "ass" in a tiny room absent EQ adjustment].

Your box could be made of grout filled cc block [I hate sand as a wall filler - if holes need to be drilled later you have a problem] - something on the order of a 4' cube with walls of cc block and a roof of a dozen or so layers of drywall perhaps? Then line the interior surfaces with thick mineral wool and build a stout well sealed door with a compression latch so you can roll a cabinet into the chamber and seal it up air tight.

BTW MSM walls are functional, but replacing the S [spring] with more M [mass] generally makes for a better iso partition - the caveat would be the efficiencies obtained from MSM if you accomplish mechanical decoupling of the two leaves in your MSM version, and have a large dampened cavity for a S, and the two sides of the wall [the M's] are quite massive. A straight mass approach is an easier way to make highly effective iso partition on such a small scale I would think, particularly given you have a bit of spare material on hand.

Good Luck!

Pics or it didn't happen
Old 23rd January 2007
  #9
Lives for gear
 
HudHudson's Avatar
 

I am looking for a similar solution and found this:

http://www.vocalbooth.com/products/ampboxes.html

Don't know how much attenuation one could expect with this little mass but worth checking out.
Old 2nd February 2007
  #10
Gear Addict
 
JesseJ's Avatar
 

Quote:
Originally Posted by Scott R. Foster View Post
I have that Randall Iso cab and it is very nice.
Old 2nd February 2007
  #11
Deleted User
Guest
Quote:
Originally Posted by JesseJ View Post
I have that Randall Iso cab and it is very nice.
What kind of heads are you using with the Randall iso cab? Can it handle the power from an amp like a Dual Rectifier? How does it sound? I'm looking for a solution for recording guitars in my apartment since I'm getting noise complaints every time I try!
Old 2nd February 2007
  #12
Lives for gear
 
el cochino's Avatar
 

Quote:
Originally Posted by nerogtr View Post
What kind of heads are you using with the Randall iso cab? Can it handle the power from an amp like a Dual Rectifier? How does it sound? I'm looking for a solution for recording guitars in my apartment since I'm getting noise complaints every time I try!
I have one, too, and there's a few things you should know about the iso cab. First of all, it's not that quiet. If you put it in the control room, you'll have a hard time listening to your CR monitors. I've used it with JCM800s, 50 and 100 watts, and never had a problem of over powering the cab. It doesn't say how much it can take, since there is no manual for it. The sound is kinda boxy, which is a result of it's small dimensions and poor absorbtion on the inside. I'm going to put some insulation inside, but I'm not sure yet what would be the best way to do it. I'm gonna try some Auralex foam or rigid fiberglass and see what works best.

The choice of mics is also important to get a decent sound out of the cab. I noticed that the e609 does a better job than the sm57. I'll also try different speakers like a Celestion G12K-100 or EV EVM 12L, since the vintage 30s are already a little nasal sounding.

The Randall iso cab is great to get a miced speaker sound at decent levels, although it sounds better when the lid is open, but then you could just use any cab. However, I'm in the same position as you are, so I've experimented a long time to get great sounding guitars in my apartment. I've been through Pods, Sansamp, H&K Tubeman and what not, but was never satisfied with the results I've got. Finally, I discovered a way to get huge sounding guitars at bedroom level - here's my recording chain: I connect one speaker output to the iso cab and the other one to a Sequis Motherload speaker simulator. The sequis goes into the di input of a Chandler TG-2, which takes away the fizz without making the guitars sounding dull. The di works much better than the mic input and I've tried all kinds of other pres and dis, as well. The iso cab is miced with a e609 and goues into a Telefunken V72. This would normally not be my goto pre for guitars, but in this case it smokes the TG-2. Now I mix the two signals until I get the desired sound and for the first time, I'm really satisfied with the results.
Old 2nd February 2007
  #13
Gear Addict
 
JesseJ's Avatar
 

Quote:
Originally Posted by nerogtr View Post
What kind of heads are you using with the Randall iso cab? Can it handle the power from an amp like a Dual Rectifier? How does it sound? I'm looking for a solution for recording guitars in my apartment since I'm getting noise complaints every time I try!
I wouldn't be feeding it with lots of power/ high volume. Actually I'd rather be feeding it with a 1W amp (ala Zvex) or so if I wouldnt have all of these at my proposal:



and



Pic I

#1. Is a Randall MTS series head

#2. The Randall Isolator

#3. Randall Greenback celestion box

Pic II

some of almost all the MTS tube pre's I have. (I love these!). thumbsup

That's my studio setup. It is a very versitile setup to work with. I can dial in a certain sound in just seconds by just changing the pres.

I haven't tried the isolator yet with really hard volume, only on low or moderate volume. If driven powertubes are what I'd want, I would go trough a powersoak (pick one for your taste) and *then* to the iso/1xgreenback at moderate level or then blast at full volume, since I do not have problems with any naighbours at the studio, only conserned about leakage when tracking and so...

It can sound boxy yes, with too much volume (what's that?). I would have designed the ISO a bit differently too.
Old 2nd February 2007
  #14
Deleted User
Guest
thats a crapload of randall gear haha.

@ el cochino: Thanks for the advice man. What I'm thinking about doing for now is tracking with a POD when I'm in my apartment so its quiet (and so we can take our sweet time), but also recording the direct signal into pro tools. Then I can reamp the performance later elsewhere where noise isn't an issue. It would still be nice to track real guitars in the apartment though. I have a walk in closet so I've been contemplating building a "room in a room" (just big enough to fit a 4x12) in there for some isolation. Could get pricey though =\.
Old 2nd February 2007
  #15
mds
Lives for gear
 

This iso box was pretty impressive when I used it: http://www.jlhproducts.com/axetrak/

The cool thing about it is they custom designed the speaker to sound good inside a box. When you put a 12 inch speaker in a box the bass response goes bananas. They designed a smaller speaker to sound like a typical 12" celestion, but to avoid the problems of a completely enclosed cab. I tried one with a 100 watt head cranked and I could BARELY hear it sitting right next to it...

Mike
Old 2nd February 2007
  #16
mds
Lives for gear
 

Oh yeah, they have a bass model too...
Old 2nd February 2007
  #17
Gear Addict
 
JesseJ's Avatar
 

Cool.. thanks for the info on the axetrak!
Combine that with the Zvex Nano amp! http://zvexamps.com/amp_view.html and you have a really silent system.
Old 2nd February 2007
  #18
Lives for gear
 
uncle duncan's Avatar
 

The problem with an isolation box is you're de-coupling the live sound from the guitar, so you don't benefit from the soundwaves interacting with the guitar, giving you more sustain and feedback. That's the whole point of playing loud, right? So get a little amp and sit right in front of it. Epiphone Valve Junior breaks up nicely, and it's only 5 watts.
Old 2nd February 2007
  #19
Gear Addict
 
JesseJ's Avatar
 

Quote:
Originally Posted by uncle duncan View Post
The problem with an isolation box is you're de-coupling the live sound from the guitar, so you don't benefit from the soundwaves interacting with the guitar, giving you more sustain and feedback. That's the whole point of playing loud, right? So get a little amp and sit right in front of it. Epiphone Valve Junior breaks up nicely, and it's only 5 watts.
Ah the age old question, to have a nice feedback or to get killed by a neighbour at 4 am

You are absolutely right there. But we have an pod generation growing up that never played with feedback, all they ever did is practice with headphones, so for them that would not be a problem.

- Jesse -
Old 2nd February 2007
  #20
mds
Lives for gear
 

I'd argue that the reason for playing loud is to get the output tubes to give it up...I don't think you need to be cranked to get some feedback love from your guitar. Play in the control room at a kinda loud listening level and you'll get feedback nicely without being nearly as loud as a cranked amp...
Post Reply

Welcome to the Gearslutz Pro Audio Community!

Registration benefits include:
  • The ability to reply to and create new discussions
  • Access to members-only giveaways & competitions
  • Interact with VIP industry experts in our guest Q&As
  • Access to members-only sub forum discussions
  • Access to members-only Chat Room
  • Get INSTANT ACCESS to the world's best private pro audio Classifieds for only USD $20/year
  • Promote your eBay auctions and Reverb.com listings for free
  • Remove this message!
You need an account to post a reply. Create a username and password below and an account will be created and your post entered.


 
 
Slide to join now Processing…
Thread Tools
Search this Thread
Search this Thread:

Advanced Search
Forum Jump
Forum Jump