hulika

Author Topic: DIY Acoustics and Soundproofing Thread  (Read 245204 times)

Offline Agent_So

  • Veteran Member
  • ****
DIY Acoustics and Soundproofing Thread
« on: November 25, 2006, 10:48:12 AM »
guys, i decided to create this thread para sa mga gusto magtanung at matuto mag acoustic and soundproof like me.. ive been doin research sa net, and ngtanung narin dito dati regarding studio acoustics.. i hope mag post rin tayo dito ng mga ginawa nating mga DIY acoustic/soundproof... pics or ideas.. now, gumawa ako 6 panel basstraps sa ceiling sa studio, ginamit ko yung design ni ethan winner...  now my question is, how to test it effectivity??


ill post some pics later.. marami pa ako tanung like how to soundproof yung main door sa studio.. pakita ko rin pics later...


i hope this thread will help many musikero's!
Solemn Harmony Studio
Blk-1, Lot-7, Diamond St., Silverhomes Classic, Perpetual Village 7, Bacoor, Cavite. CELL: 0915-492-2800 (Premier,Peavey,Hartke,Mackie,JBL,Shure,DBX,Zoom)

Offline Direk

  • Senior Member
  • ***
Re: DIY Acoustics and Soundproofing Thread
« Reply #1 on: November 27, 2006, 03:02:36 AM »
gumawa ako 6 panel basstraps sa ceiling sa studio, ginamit ko yung design ni ethan winner...  now my question is, how to test it effectivity??

Agent So,

Yan din sana yung itatanong ko sayo eh. According to you, its a bass trap. Now my question is, anong offending bass frequency (or room resonance modes) ba reflected from the ceiling(???) ang kinonsider mong ma treat? Have you consider calculating your room's resonant mode before? Dito mo malalaman yung behavior ng resonance modes after ma-excites ng sound yung  room mo which cause frequency-response peaks and dips and this affects the frequency modes up to 300Hz, beyond this, it tends to become so dense that it dont cause problems. This explain why we always concentrate more on treating the bass problem in a room.   

To test your room behavior(kung nagawa mo sana muna to before then thru comparison, malalaman mo kung effective nga ang bass trap project mo), you need a Test CD with diagnostic tracks like covering Bass Decade with 1/3-octave warble tones at -20dbFS ( 20Hz, 25Hz, 31.5Hz, 40Hz, 50Hz, 63Hz, 80Hz, 100Hz, 125Hz, 160Hz and 200Hz respectively). Also, a sound level meter (Radio Shack, Cat.#. 33-2055...hint:cheap) will help you to plot your rooms resonance modes. For hi tech approach, a spectrum analyzer with calibrated mic's will do but at a cost . Hope this helps.     


 

Offline toink

  • Senior Member
  • ***
Re: DIY Acoustics and Soundproofing Thread
« Reply #2 on: November 27, 2006, 11:40:03 AM »
mga sir ask ko po kung pano isoundproof ung ceiling. mukhang manipis lng ung ceiling dito eh, kisame tapos konting space den yero na agad. pano po kaya sir? and kapag concrete po b ung pader ok na un? di n kelangan pang lagayn ng soundproof ung pader? di nmn kelangan totally na masoundproof, important lng hindi maingay sa labas, khit konting may naririnig ok lng basta hindi nakakaistorbo. tnx! :)
toink!

Offline Blueberri

  • Senior Member
  • ***
Re: DIY Acoustics and Soundproofing Thread
« Reply #3 on: November 27, 2006, 03:44:12 PM »
mga sir,

same question as above, how much does a concrete wall take off the sound?? would a loudly played drum set still be annoying on the other side?? (lets take that there's no bleed off the ceiling).

and would a nice big couch work as a bass trap??Also, where would be the best placement??(in a mixing room)
or how do i find out where?? can I go around the room and listen to where bass is the loudest??

thanks!

Offline skunkyfunk

  • Philmusicus Addictus
  • *****
Re: DIY Acoustics and Soundproofing Thread
« Reply #4 on: November 27, 2006, 03:53:10 PM »
People need to go to school, or at least learn a little Physics first. 

Just as a simple check, try playing a really good bass guitar through a great sounding bass amp.  Then find out what notes in the bass guitar seem to shake the walls - that woukld give you an idea what resonant frequencies have to be corrected.



Offline mikep

  • Forum Fanatic
  • ****
Re: DIY Acoustics and Soundproofing Thread
« Reply #5 on: November 27, 2006, 06:35:33 PM »
We're seeing some good points here.  Direk's suggestion is very good.  You can try that approach to see what LF resonates the room.  Skunkyfunks suggestion is good as well.  The important thing is that you should know the different frequencies of the various keys or note, i. e., open E string is 40 hz., etc.

To soundproof a room, a 6 inch CHB will give you an STC of about 43.  You paint the pores, it become 45.  If you sound is about 100 dB, you still have to contend with something like 55 dB, which is still a lot of sound.  If you are talking of a practice room for drums, it may not affect your neighbors anymore as long as you do not practice during late evenings.  For recording, noises from the outside can still affect your recording especially during soft passages.  You have to remember that you have to control sound coming out and coming in to the studio or room.

How do you treat your roof?  Put glass fiber insulation under the GI sheets, about 50 mm, held by GI wire.  Then, allow an air gap.  Then install at least 2 pieces of 12mm gypsum board on ceiling sleepers.   Put about 100 mm of glass fiber batt, the one that is rolled, 16 or 38 kgm, whatever you can afford, on top (inside) of the gypsum ceiling.  Caulk all joints and possible areas where sound can seep through with silicon caulk or better yet, any non-hardening caulking material.  After which you deal with the acoustics of the room.  Put heavt drapes on 2 sides of the room from top of wall to floor.  Put them so that the drapes are about 3 to 4 inches away from the wall.  For the ceiling, install acoustical tile.  For the floor, ordinary wood or T & G wood flooring.

So, there.  A less expensive way of soundproofing and taming your room acoustics.  As to the modes, that's another story.  You have to go through room ratios and if there are still problems, specific traps using resonators like Helmholtz ones to tame resonating frequencies.

Where to put traps?  At the back where the waves develop into their full potential.  Also, the areas where the side walls meet the back wall.  Bass tends to deveop in those areas.  In the ceiling?  Normally you put mid frequency absorbers there. 

How big must the trap be?  Definitely if you talking about low frequencies, you need more space to trap it.  The trap should have at least a depth of 12 inches (.30 mtrs.).

Direk is right.  You just do not put bass traps if there are not offending frequencies in the room.  You might be over doing it and destroy the sound of your room.

FWIW
www.facebook.com/TRACKSAcoustics/Studios
guitars: gretsch 6122-1962; rickenbacker 330; epi elite casinos; gibson les paul standards, tribute, faded, double cut; gibson sg standards, faded; fender strats MIAs, MIJs, MIMs; fender tele MIAs, MIJs, MIMs; etc

Offline Direk

  • Senior Member
  • ***
Re: DIY Acoustics and Soundproofing Thread
« Reply #6 on: November 28, 2006, 04:24:58 AM »
As to the modes, that's another story.  You have to go through room ratios


Let's consider first what happens along the length of a room when the air inside is excited by sound from the loudspeakers. A room's resonant frequencies are determined by the distance between the room's wall. The farthest apart the walls are, the lower the resonant frequency. Specifically, the lowest resonant frequency called the fundamental resonance, occurs within the room's length equals the half wavelength of sound. Put another way, a resonant mode will occur when the sound's wavelength is twice the length of the room. Other resonant modes occur at twice this frequency, three times this frequency, and so on. Whenever the length of the room is a multiple of half of the sound wavelength, a resonant mode will occur.

Here's an example and how to determine your room resonant modes based on your room's length, width, and height. The formula is F1 = 1130/2L. F1 is the first resonant mode, 1130 is the speed of sound in air (in feet per second), and 2L is two times the room's length (in feet). If the room is 21' long, its first resonant mode (F1) will be 27Hz (1130/2 x 21).

We know that the next mode will occur when the wavelength equals the room's length, at 54Hz (2 x F1), then again at the next multiple of half a wavelength ( 1- 1/2 wavelengths) at 81Hz (3 x F1), again at 108Hz (4 x F1), and so forth. Again, it is only necessary to consider room modes up to 300Hz.

The room's height and width will also create their own resonant modes. If we have an 8' ceiling, the resonant modes will occur at 71Hz (1130/2x8), 141Hz , 212Hz, and so on. If the width is 13', the resonant modes modes will be at 43Hz (1130/ 2 x 13), 87Hz, 130Hz, 174Hz, 217Hz, 261Hz, etc. We end up with a chart that look like this:
 
Mode    Length    Width    Height
                21'          8'           13'

F1           27Hz       71Hz      43Hz
F2           54Hz       141Hz    87Hz
F3           81Hz       212Hz    130Hz
F4           108Hz     282Hz    174Hz       
F5           135Hz     353Hz    217Hz     
F6           162Hz                   260Hz             
F7           189Hz                   304Hz             
F8           216Hz
F9           243Hz
F10         270Hz
F11         297Hz
F12         324Hz         


Interpreting the resonance modes; Let's say for room distance, L24', W16', H8'; Length mode (F3) at 72Hz, coincides with the second mode width (F2) 70Hz and the first height mode (F1) 71Hz,  these combine modes, will pile-up creating a huge peak in the response at this frequency. This undesirable situation occurs because the room's length, width, and height are multiples of each other. Expect a thick, peaky, and very colored  bass reproduction. 

We can minimize the frequency-response peaks and dips caused by room resonance modes by choosing a room ( this isn't always possible unless you build a room from scratch, or convert a garage or basement into a listening/monitoring/studio room)  with dimensional ratios that more evenly spread the resonant modes over the low-frequency band. This gives you a head start in getting great sound from your system.
Goodluck!
 
« Last Edit: November 28, 2006, 04:30:22 AM by Direk »

Offline mikep

  • Forum Fanatic
  • ****
Re: DIY Acoustics and Soundproofing Thread
« Reply #7 on: November 28, 2006, 07:28:27 PM »
Korek, Direk (it rhymes, too).  The terms are axial, tangential and oblique modes.

FWIW
www.facebook.com/TRACKSAcoustics/Studios
guitars: gretsch 6122-1962; rickenbacker 330; epi elite casinos; gibson les paul standards, tribute, faded, double cut; gibson sg standards, faded; fender strats MIAs, MIJs, MIMs; fender tele MIAs, MIJs, MIMs; etc

Offline toink

  • Senior Member
  • ***
Re: DIY Acoustics and Soundproofing Thread
« Reply #8 on: November 28, 2006, 08:22:03 PM »
How do you treat your roof?  Put glass fiber insulation under the GI sheets, about 50 mm, held by GI wire.  Then, allow an air gap.  Then install at least 2 pieces of 12mm gypsum board on ceiling sleepers.   Put about 100 mm of glass fiber batt, the one that is rolled, 16 or 38 kgm, whatever you can afford, on top (inside) of the gypsum ceiling.  Caulk all joints and possible areas where sound can seep through with silicon caulk or better yet, any non-hardening caulking material.  After which you deal with the acoustics of the room.  Put heavt drapes on 2 sides of the room from top of wall to floor.  Put them so that the drapes are about 3 to 4 inches away from the wall.  For the ceiling, install acoustical tile.  For the floor, ordinary wood or T & G wood flooring.

sori po sir medyo hindi ko naintindihan hehe. saan po b ako makakabili ng mga ganyang gamit? my room is 9 1/2 x 16 1/2 feet. mga magkano kaya gagastusin sa soundproofing nung roof
toink!

Offline Direk

  • Senior Member
  • ***
Re: DIY Acoustics and Soundproofing Thread
« Reply #9 on: November 28, 2006, 09:00:26 PM »
Korek, Direk (it rhymes, too).  The terms are axial, tangential and oblique modes.

FWIW

By the way, this explanation of room resonance modes and the examples given are greatly simplified. I've just covered what are called axial mode--those that exist between one pair of surfaces. Other modes resulting from the two surfaces pairs (tangential modes) and three surfaces pairs (oblique modes, from all six walls of a room) aren't discussed.

Offline TheHunter

  • Senior Member
  • ***
Re: DIY Acoustics and Soundproofing Thread
« Reply #10 on: November 28, 2006, 10:03:23 PM »
are there any acoustic simulation software available?
Let your ears teach your fingers.  :wink:

Offline Direk

  • Senior Member
  • ***
Re: DIY Acoustics and Soundproofing Thread
« Reply #11 on: November 29, 2006, 01:29:09 AM »

Offline mikep

  • Forum Fanatic
  • ****
Re: DIY Acoustics and Soundproofing Thread
« Reply #12 on: November 29, 2006, 01:42:13 AM »
There are several, but you should be careful with these acoustic simulations and software.  They are just tools that you use.  An understanding (again) of the basics is necessary to fully make use of these elements.  Read on and study some more.  Books of F. Alton Everest on acoustics are very nice reads.

FWIW
www.facebook.com/TRACKSAcoustics/Studios
guitars: gretsch 6122-1962; rickenbacker 330; epi elite casinos; gibson les paul standards, tribute, faded, double cut; gibson sg standards, faded; fender strats MIAs, MIJs, MIMs; fender tele MIAs, MIJs, MIMs; etc

Offline Agent_So

  • Veteran Member
  • ****
Re: DIY Acoustics and Soundproofing Thread
« Reply #13 on: December 26, 2006, 01:02:55 PM »
mga sir, anu bang magandang pang soundproof sa pinto?? im thinking of using 4inch thick styro... would that do the job? advise mga sir thanks.!

regarding dun sa mga ginawa kong basstrap, as i can see it has big effect sa low frequency dampening pero di ko pa talaga matest gaano siya ka effective..

anyways, eto lang pansin ko sa room ngayon, sa key of "A" ngba-vibrate yung mga glass windows.. anu kaya ibig sabihin nun?

btw, yung room is not yet fully acoustic, kulang pa sa buget eh.. pero yung initial na mga nilagay kong sound absorbers, does the job well...

anyways, i hope you can help me in soundproofing my door... kaya naiisip ko na styro kasi mas solid siya sa foam... what do you think guys?
Solemn Harmony Studio
Blk-1, Lot-7, Diamond St., Silverhomes Classic, Perpetual Village 7, Bacoor, Cavite. CELL: 0915-492-2800 (Premier,Peavey,Hartke,Mackie,JBL,Shure,DBX,Zoom)

Offline mikep

  • Forum Fanatic
  • ****
Re: DIY Acoustics and Soundproofing Thread
« Reply #14 on: December 27, 2006, 01:13:34 AM »
mga sir, anu bang magandang pang soundproof sa pinto?? im thinking of using 4inch thick styro... would that do the job?

regarding dun sa mga ginawa kong basstrap, as i can see it has big effect sa low frequency dampening pero di ko pa talaga matest gaano siya ka effective..

anyways, eto lang pansin ko sa room ngayon, sa key of "A" ngba-vibrate yung mga glass windows.. anu kaya ibig sabihin nun?

btw, yung room is not yet fully acoustic, kulang pa sa buget eh.. pero yung initial na mga nilagay kong sound absorbers, does the job well...

anyways, i hope you can help me in soundproofing my door... kaya naiisip ko na styro kasi mas solid siya sa foam... what do you think guys?

Styro is not a good sound stopper.  It can probably absorb sound, but for doors, you need mass.  You can do a sandwiched type door, with different facing thicknesses.  Then, you have to put a lot of rubber stripping around the door and jamb.  The door is a weak link, and it surely is a source of sound seeping through another room.  The technique is to build a sound lock.

Regarding your glass vibrating, that means your glass window is resonating at that frequency.  First, you have to put silicon caulking around the edges of the glass to secure it well.  Second, you have to make sure the measurement and thickness of the glass will not vibrate and resonate at that frequency.  It's either you make the glass thicker or make the size smaller.

Acoustics is not an easy thing.  You need understanding of basic physics - the characterics of sound, etc.  You can experiment but you also have to study by reading books and other acoustic articles or materials.  If you do not know what you're doing, you'll be wasting lots of money.

Good luck.

FWIW
www.facebook.com/TRACKSAcoustics/Studios
guitars: gretsch 6122-1962; rickenbacker 330; epi elite casinos; gibson les paul standards, tribute, faded, double cut; gibson sg standards, faded; fender strats MIAs, MIJs, MIMs; fender tele MIAs, MIJs, MIMs; etc

Offline KitC

  • Prime Moderator
  • *****
Re: DIY Acoustics and Soundproofing Thread
« Reply #15 on: December 27, 2006, 02:10:08 AM »
Mike,

I've read of quarter-inch thick clear vinyl being used as dampers for glass windows. You don't even have to cover the entire pane, about 1/5 to 1/4 is enough and the inherent 'stickyness' of vinyl is enough for it to stick to glass. Question is... where does one get clear vinyl of sufficient thickness here?
Sonar 4.04PE/5.2PE/7.02PE/8.31 PE, Project 5 v2.5.1, EmulatorX 1.5, Cubase SL2, Ableton Live 7.14,  Intel Q6600 MSI P43 Neo 4Gb Crucial Ballistix Tracer DDR2-800, Emu 1820m, Yamaha DSP Factory, Terratec DMX 6fire

Offline mikep

  • Forum Fanatic
  • ****
Re: DIY Acoustics and Soundproofing Thread
« Reply #16 on: December 27, 2006, 02:31:06 AM »
What you're talking about, Kit, are what are termed as "limp masses."  These are indeed vinyls and rather thick.  Because they do not conduct sound, the characteristic of the material proves so, they are very good sound stoppers.  Normally, you put them in between walls as "mass sheetings" to insulate sound from being transmitted.  There is a brand from Australia that is very good.  It's called Deci-Bar CB with CB standing for Clear-view Noise Barrier.  A friend use to import it.  But because it is very expensive and not a lot of people use it (because of the cost), he has stopped importing it.  So, ... yes, there are acoustic materials like you mentioned but the cost factor is rather a matter to contend with.

A better alternative is tempered glass.  The physical construction of tempered glass permits it from stopping the conductance of sound energy.  A 3/8" tempered plate glass doubled by a 1/2"tempered glass also on the other side can give you very good STC numbers.  In my case, I use differing plate glasses, not necessarily tempered ones (again, expensive), but make use of a big air gap in between, and making sure that the walls are totally isolated from one another.  How to do that is another story.

FWIW
www.facebook.com/TRACKSAcoustics/Studios
guitars: gretsch 6122-1962; rickenbacker 330; epi elite casinos; gibson les paul standards, tribute, faded, double cut; gibson sg standards, faded; fender strats MIAs, MIJs, MIMs; fender tele MIAs, MIJs, MIMs; etc

Offline mikep

  • Forum Fanatic
  • ****
Re: DIY Acoustics and Soundproofing Thread
« Reply #17 on: December 27, 2006, 02:32:40 AM »
Question is... where does one get clear vinyl of sufficient thickness here?

Not available here (anymore).  You have to import it.

FWIW
www.facebook.com/TRACKSAcoustics/Studios
guitars: gretsch 6122-1962; rickenbacker 330; epi elite casinos; gibson les paul standards, tribute, faded, double cut; gibson sg standards, faded; fender strats MIAs, MIJs, MIMs; fender tele MIAs, MIJs, MIMs; etc

Offline Blueberri

  • Senior Member
  • ***
Re: DIY Acoustics and Soundproofing Thread
« Reply #18 on: December 28, 2006, 11:09:43 PM »
question po mga sir,

Does hardiflex have better soundproofing properties than ordinary plywood?? so would it be better to use them making doors and for ceilings??

thanks!

Offline mikep

  • Forum Fanatic
  • ****
Re: DIY Acoustics and Soundproofing Thread
« Reply #19 on: December 29, 2006, 02:11:09 AM »
Yes, a 1/4" hardiflex or cement board would have almost the same STC as a 1/2" gypsum.  The problem is, they are heavy.  Hence, after a while your door will droop and you would have a hard time closing it.  They are better used for walls in place of wall boards or gypsum.  They are also heavy for ceiling.  Gypsum would be better for that.  Aside from those things, another matter to consider is, they are expensive.  1/4" Hardi is more expensive than 1/2" gyp.  I'd still go for gypsum or wall boards.

For doors, you are better off using wood, plywood designed in a "sandwiched" manner.  The other alternative would be steel with honeycomb inserts and isolation.  As to how to do that is a little complicated.  That is the reason why they sell acoustically rated doors commercially and they are expensive.

So, what do you do?  First, do you really need an acoustically rated door?  The way to do it, as I mentioned earlier, is to have a soundlock.

As I mentioned previously, acoustics is no easy task.  You're talking here of just isolation.  How about the response of your room?  That's where things become complicated.  Remember Direk's posts on room modes and  other things?  Those are just a portion of it.

FWIW 
www.facebook.com/TRACKSAcoustics/Studios
guitars: gretsch 6122-1962; rickenbacker 330; epi elite casinos; gibson les paul standards, tribute, faded, double cut; gibson sg standards, faded; fender strats MIAs, MIJs, MIMs; fender tele MIAs, MIJs, MIMs; etc

Offline Agent_So

  • Veteran Member
  • ****
Re: DIY Acoustics and Soundproofing Thread
« Reply #20 on: January 08, 2007, 03:00:05 AM »
mga sir i really need help here... so basically 1/2" gypsum boards will do the job in isolating sound leaking thru my door?? i dont really need a 100% isolation.. i just want to minimize the sound coming out my entrance door.. ang lakas kasi, nakakahiya na sa mga kapitbahay kapag may ng jam ng gabi..

another thing, yung gypsum board ba pwede ka mag pa customize ng size, kasing size ng door? and how do you install it?? thanks again mga sir...
Solemn Harmony Studio
Blk-1, Lot-7, Diamond St., Silverhomes Classic, Perpetual Village 7, Bacoor, Cavite. CELL: 0915-492-2800 (Premier,Peavey,Hartke,Mackie,JBL,Shure,DBX,Zoom)

Offline mikep

  • Forum Fanatic
  • ****
Re: DIY Acoustics and Soundproofing Thread
« Reply #21 on: January 08, 2007, 10:59:25 PM »
I do not recommend gypsum for doors.  It is too heavy and can break easily if the door is opened or closed rather more than occasionally.  I would go for wood doors with insulation inside.  Also make sure that the surrounding edges would have something like neoprene gaskets to stop sound from coming out.  Refrigerator seals are very good alternatives aside from the Riven weather rubber seals you can get at True Value or Ace Hardware.

Search the net for door designs.  You can get ideas from them.

FWIW
www.facebook.com/TRACKSAcoustics/Studios
guitars: gretsch 6122-1962; rickenbacker 330; epi elite casinos; gibson les paul standards, tribute, faded, double cut; gibson sg standards, faded; fender strats MIAs, MIJs, MIMs; fender tele MIAs, MIJs, MIMs; etc

Offline Agent_So

  • Veteran Member
  • ****
Re: DIY Acoustics and Soundproofing Thread
« Reply #22 on: January 08, 2007, 11:37:24 PM »
thanks sir! bumili ako nung riven na yun, yung nabibili sa ace.. badtrip. ayaw naman dumikit. nasayang lang...  hehehe... actually binili ko yun para pang isolate naman ng lamig.. hanap nalang rin ako nung refregerator seals na yan.. mukhang maganda nga.. yung main door namin sir is yung solid door siya.. hindi hollow yung loob nya.. cge hanap ako sa net ng door design..pero i guess hindi na kami makakapag palit ng pintuan... hindi na kaya ng buget. hehehe..  sana may alternative pa.. im also thinking of using thick foam....
Solemn Harmony Studio
Blk-1, Lot-7, Diamond St., Silverhomes Classic, Perpetual Village 7, Bacoor, Cavite. CELL: 0915-492-2800 (Premier,Peavey,Hartke,Mackie,JBL,Shure,DBX,Zoom)

Offline mikep

  • Forum Fanatic
  • ****
Re: DIY Acoustics and Soundproofing Thread
« Reply #23 on: January 09, 2007, 10:40:41 PM »
Don't use foam.  Dangerous.  Plus, it can absorb sound but not stop it.  What you need to stop sound is something solid - massive.  Useless to use it for doors.  Use solid core doors and put weather strips around the jambs - side, top and bottom.  That way you eliminate sound seepages.  Good luck.
www.facebook.com/TRACKSAcoustics/Studios
guitars: gretsch 6122-1962; rickenbacker 330; epi elite casinos; gibson les paul standards, tribute, faded, double cut; gibson sg standards, faded; fender strats MIAs, MIJs, MIMs; fender tele MIAs, MIJs, MIMs; etc

Offline BAMF

  • Board Moderator
  • *****
Re: DIY Acoustics and Soundproofing Thread
« Reply #24 on: January 09, 2007, 11:03:28 PM »
Our studio used foam balloted, este, wrapped in fabric. I even used rebonded undermat (foam used underneath carpets) because it's the cheapest of the lot.  Well...yeah I'm on a tight budget. Anyway, attenuation is quite good, so is the sound treatment. The massive 6" Jackbilt hollowblocks from which the walls are made from also help a lot. I still get sound seepage through the door and aircon hole though, and through a small portion in the ceiling. But for the most part, I'm told that the aircon upstairs is actually louder than the drummer in the studio beating like there's no tomorrow.

I think I have to buy a rather large fire extinguisher.
Doghouse Recording Studio: http://doghousestudio.webs.com
Cel: 09282843633