Hi !

My name is Jasenko and I am living in Croatia.I play mix of blues and jazz using acoustic guitar, electric guitar,bass using DI on the mic pre,voice and small percussion instruments.So,I do not use drums,the bass is going directly and I am not playing loud.I am planning to build a home studio in my basement.I was reading a lot on the Internet and I have an idea how this studio should look like.There are only few things I am not certain about and for that I need some advices .

My basement is about 43,2 cubic metres of space.The ceiling is 2.36 m from the floor( it will be 2.2 m after full covering of the ceiling with Tervol solid rockwool and mounting of the wooden floor).The floor will be covered with 2,2 cm thick black pine wood.The other room dimensions are :

-Longest wall( blue colour)is 5.35 m.It is 40 cm thick concrete wall and on the other side of this wall is solid ground.I am planning to cover it with 2 cm thick Tervol + 1 cm of air + 1.25 cm of plaster.WHAT DENSITY OF TERVOL SHOULD I USE HERE ( 30,50,70 or 100 kg per cubic meter )?ALSO ,SHOULD I PUT SOLID OR SOFT TERVOL HERE? SHOULD I LEAVE 1 CM OF AIR OR INSTEAD PUT 3 CM OF TERVOL AND NO AIR AT ALL?

-Opposite to this is 4.35( green colour ) m long,40 cm thick concrete wall.On the other side of this wall is the air because this is the wall to the yard.On the end of the yard is yard of the house near by,the house and very quiet cul-de-sac.This wall I will cover with 2 cm thick Tervol + 1 cm of air + 1.3 cm of black pine wood.IS THAT A GOOD IDEA TO GET DIFFERENT OPPOSITE SURFACES( regarding the esthetics of the interior I would rather put plaster on all four walls,but if there will be significant sound improvement with the wood on that wall ,I will put the wood)?

-The wall on the right(yellow colour ) looking forward from the longest wall is 4 m long ,40 cm thick concrete wall and on the other side of this wall is solid ground.This wall I will cover with 2 cm thick Tervol + 1 cm of air + 1.25 cm of plaster.WHAT DENSITY OF TERVOL SHOULD I USE HERE ( 30,50,70 or 100 kg per cbm )?

-Opposite to this wall ( the wall on the left looking forward from the longest wall)is the wall that I will build ( red colour)to be separated from the rest of the basement which I need for other purpose.This wall will be made of 2.50 cm plaster + 1.25 cm of air + 5 cm of Tervol + 1.25 cm of air + 2.50 cm of plaster( in total it will be 12.5 cm ).Here I will use some denser plaster.WHAT DENSITY OF TERVOL SHOULD I USE HERE?On this wall I will build the entrance door to the studio.

Now about the acoustic treatment.I am planning to cover all ceiling with 8 cm thick solid Tervol sealed in burlap bags.WHAT DENSITY OF TERVOL TO USE HERE ? .I will put bass traps in all corners from floor to the ceiling using 10 cm thick Tervol(WHAT DENSITY TO USE HERE ?) and I will put 4 cm thick( OR SHOULD I USE 6 CM AND WHAT DENSITY TO PUT HERE?) Tervol in First Reflection Points( RFZ panels ) and on few other places.

Also I will put two-directional diffusors on the rear wall with some bass traps bellow them.I will have only a few pieces of equipment and speakers in the room and I will have them on the wheels so that I can shift them inside the room .The computer will be out of the room in order to minimize the noise.


The orientation on RECORDING MODE drawing is more suitable for recording with the diffusors on the rear wall for reflection while recording.Also the volume of the room is in its largest option ( 43,2 cbm).

My idea is to orientate the room differently while mixing(MIXING MODE NO.1 drawing).That is how I will get the flat front wall so the distance from both speakers can be the same from that wall.I will put some RFZ panels on the front wall behind the speakers and shift the diffusors on the back wall.Now the biggest question is:

If I make the rear wall as on the MIXING MODE NO 2. drawing,what will I get?Will there be some significant improvement in diffusion if I build a portable wall?In that case the volume of the room will be smaller for 2.2 cbm ( 41 cbm).Or should I keep the original shape of the room (as in MIXING MODE NO.1) with the volume of 43.2 cbm and just orientate the room differently and shift the diffusors to the back wall?

My main goal is to make the room suitable for recording ( only for my kind of music ).Mixing can be done in a professional studio but in that case I will need to travel to another town and pay for the studio time,gasoline and all other costs.So I want to adjust the room to be suitable for mixing too.What are Your opinions about my plans?Are there any chances that this will work out?

Down bellow You can find first the three above mentioned drawings( RECORDING,MIXING NO 1,MIXING NO 2) and then the five photos( BLUE,GREEN,YELLOW,RED,VIEW FROM THE STAIRWAY) of the basement in its present condition.

Sorry for the long post ,greetings and many thanks in advance !

Jasenko

P.S. The markings for RFZ panels and diffusors are not aligned nicely on the drawing,but it is good enough that You get the idea.In reality it will be done properly.

http://farm4.static.flickr.com/3466/3878409344_76c1959acf_b.jpg

http://farm3.static.flickr.com/2421/3878422546_f6b9ce1d7e_b.jpg

http://farm3.static.flickr.com/2445/3878438182_8a46be7a16_b.jpg

http://farm3.static.flickr.com/2445/3878438182_8a46be7a16_b.jpg

http://farm3.static.flickr.com/2655/3877661563_359ea6f707_o.jpg

http://farm4.static.flickr.com/3454/3878457230_1f22f70458_o.jpg

http://farm3.static.flickr.com/2566/3878459140_3d138fe9ac_o.jpg

http://farm3.static.flickr.com/2608/3877665999_4bb6cf3f24_o.jpg

- Rock wool inside a wall, between cement and plaster, is for thermal insulation only. I have no idea what density is best for that, but I imagine any type of rock wool is fine there. Just pack the space with the rock wool, with no air gap.

- Wood and plaster reflect sound about the same, so there's no acoustic advantage to using wood.

- If you use 50 kgm3 density rock wool for everything that should be fine.

- Mixing Mode #2 looks the best for recording and for mixing. You want to face to the right of the drawing to keep the front of the room symmetrical, and having different front-back lengths as shown in that drawing will help the low frequency response.

--Ethan

Hi Ethan !
Thanks for the answer,it was much quicker that I expected to be.There are two things that still bother me.I wanted to put 100 kg/cbm Tervol everywhere( 4 or 6 cm thick as a RFZ panels,8 cm thick on the ceiling and 10 cm thick in corners).My idea was based on Your article in which I read that the denser is the fiberglass the more effective is the absorption in lower ranges and on the fact that I can easily find 2 cm thick Tervol of 100 kg/cbm density.One pallete of this will be just enough for my purpose (the problem here in Croatia is that one must buy larger quantities of rock wool and this quantity of 150 square meters of 2 cm thick is just what I need).I had a fear that I may overapsorb something using such a dense rockwool and that is why I post this question.If I will go with Your suggestion of 50 kg/cbm then I must buy 100 square meters of 3 cm thick Tervol ( because they do not make 2 cm thick of this density).In that case I can use 6 cm thick for RFZ,9 cm thick for ceiling and 12 cm thick for bass traps,but with one pallete I do not have enough Tervol for everything I need.So,if I use 100 kg/cbm is there a problem of overapsorbing?Note that in either case( 50 or 100 kg/cbm) I am planning to use Kraft paper on some of the ceiling tiles and RFZ panels in order to not absorb too much high frequencies.Also,if I go with 2 cm thick Tervol of 100 kg/cbm should I use 4 or 6 cm for RFZ panels ( I know Yours are 2" thick but I can not make 5 cm thicknes)?

The other thing is about the diffusion.I am accepting Your advice about the MIXING MODE NO 2 ( to use it both for recording and mixing).The only thing that bother me is should I put corner bass traps,diffusors and floor bas traps bellow them on the wall of the middle well ( the longest front-back distance) or should I just cover the complete wall with diffusors and put the floor bas traps bellow them?Note that each well will be about 1,3 m wide so if I put the corner bass traps ,the diffusor will be only about 50-60 cm wide.In the other two wells I will put corner bass trap,diffusor and floor bass trap combination.
Also,should I put diffusors only on the rear wall surfaces that are facing front of the room or should I cover the complete area of rear wall including the surfaces which are up and down on the basic front-back line?

Greetings !

Jasenko

I have not tested all the densities, but when it's too dense it begins to absorb less.

6 cm is perfect for RFZ panels.

You can cover the entire rear wall with diffusors left and right. But they don't have to go all the way down to the floor, or up to the ceiling. Make them between 4 and 6 feet tall, and mount them centered at ear height.

--Ethan

Hi Ethan !

Thanks again.I manage to find a supplier who will order the quantity I need.I choosed Tervol of 50 kg/cbm.The only question now is should I order 3 cm thicknes or 5 cm thicknes?Does this matter regarding the density of the material ?
If I choose 3 cm than the RFZ panels will be 6 cm (2 x 3 cm ),ceiling tiles 9 cm (3 x 3 cm ),corner bas traps 12 cm (4 x 3 cm)and floor bas traps 15 cm (5 x 3 cm ).
If I choose 5 cm thickness then the RFZ panels will be 5 cm ( 1 x 5 cm ),ceiling tiles 10 cm ( 2 x 5 cm ),corner bass traps 10 cm ( 2 x 5 cm ) and floor bass traps 15 cm ( 3 x 5 cm ).
The dimensions of the panel in each case is 100 x 50 cm.

Greetings !

Jasenko

Get the thicker 5 cm type.

--Ethan