What would you do with this limited acoustic wool?

Y

Ytakary

New member
Hello Everybody,

This is my first post and would appreciate some input on my limited room treatment plans.

I live in South Korea and it is really difficult / near impossible for me to find any affordable bass traps, or rockwool to make my own.

However, I did manage to get hold of a few acoustic wool panels from a guy who was ripping up his studio. Unfortunately, I could only get what I could take in a taxi, and by the next day the rest was gone. They are literally just the wool with some fabric glued on the front - no frames, not even even cuts - desperate stuff. In terms of DIY, I'm limited to cutting them up and wrapping them in fabric. That's it, I'm afraid.

This is what I have to work with:

5 panels measuring 110 x 65 x 5cm (approximately)

First of all, I'm cursed with the 8x10x8(ceiling) room (approximately). Concrete walls, window, storage room. Now I understand that a 5cm thick panel is not adequate for bass trapping in such a small room, so I was thinking to cut them in half and double them up. This would give me smaller but thicker traps.

So, here is my humble plan. I would love some feedback or suggestions as to what you would do with such limited options:

1. - Make 5 bass trap panels measuring 55*65*10cm
- Hang 4 of them in the four top corners. There is a door in one, but I can use hooks and attach it when I'm mixing.
- Use the 5th panel as a ceiling cloud.

Questions: 1. Is it better to have them in the top corners rather than the bottom or middle (i.e. behind the speakers)?
2. What's more important- length or width? I could also make them 110 x 32.5 x 10, but this is very narrow.
3. Would it be better to place the 5th in the middle of the front wall? Or perhaps as two 5cm thick early
reflection panels?

As for additional treatment, it will have to be foam panels and a poor man's diffuser.


Some extra information:
20171015_160431.jpg

I understand that I won't ever be able to get anything ideal with this setup. However, my aims are to absorb as much bass as I can (I'm getting terrible standing wave cancellation in my listening position) for mixing, and sort my early reflection points enough to make passable* acoustic recordings.

As you can see in the photos, I'm currently using an old pair of Spirit Absolute 2 monitors. These are two big for my room, and, even when I had a better room in the past, I wasn't happy with them. I'm going to buy some smaller and better quality monitors (either Adam a3x / a5x / or some Genelec 1010s which have some room compensation settings). Interface is about to be upgraded too. However, I would like to see what I can do with my room first before investing. Would hate to be restricted to headphones.

*I make instrumental electronic / ambient / downtempo, and most of the acoustic recordings I use end up heavily modified or disguised, but I would love to be able to get some better acoustic guitar recordings.

Hope to hear your input :)
 
First, mixing room and recording room are two different rooms from a treatment perspective. That said, the one great thing about the technology today , most is very portable.

I suggest get your room treated for mixing. If your rig is portable, go find a place that gives your acoustic the best sound possible. Could even be outside if you have a USB interface that powers off the laptop. Presonus's USB Audio box for example, powers from the laptop. It is a decent interface and the price is not real high.

I think too many forget, there are many places to play as the sound is what the sound is, verses getting a room set for optimal mixing. If you can find that place that makes your guitar sound great, track there.
 
As mentioned above, we need to separate the reasons and effects for the room treatment. Tracking/mixing/mastering.

Tracking. The goal here is to use close mic'ing. Something like a SM57 would be a great choice. You can build something like pictured below for around $10.00 and just use a heavy blanket/quilt or something like a moving pad you would get from u-haul. You may want to add an extra side. This will keep most of the flutter out while still keeping your audio from sounding dead or boxy. You can use a condenser as well, you will just need to play around with the mic placement.

View attachment 100765

Mixing/Mastering. Now, I am going to go put on my BPV as I am sure that some will want to shoot me, for some of my next comments. You can use a cheap bookshelf, wall to wall on the wall directly behind your monitors, filled with any type of books, for GREAT diffusion. Some multi million dollar studios use this same design. You just need to go wall to wall, floor to ceiling or as much wall space as you can cover.

I would place your bass traps in the corners of the wall that is behind your mons. I will start at the top, go down as well as left and right. I would also build something like pictured above and place one end at the top where the wall meets the ceiling, and lower it around 12 inches at the point where it goes about 12 inches past where you will be sitting, as wide as it is from speaker to speaker.

Now, this is where my BPV comes into play. You may get better results using headphones, like the PS-500E. It is a little pricey, ($595.00) but we are talking about a problem that you already know exist and it may be your best solution. If you do all this, your sound will improve drastically.

To compare your room with a professional mastering room, I would also do a 3 to 4 min recording of your guitar. Use your mons or headphones to master it to the best of your ability/knowledge. Send the raw file to @MassiveMastering, pay them $75.00 to do the voodoo, that they do, so well as I have been told. I have never used their services but they do have a killer website. This will give you a reference point for future mixes.

You can also upload your raw file to this community and let others play with it as well. Once you get some results back, load them onto your phone and compare them using your ear buds. Since 60% of all music audio is consumed this way in 2017, (as per the latest stats), see if the difference is worth the $$$ you may keep sending down the rabbit hole, trying to fix a problem, that you already know can not be cured. Just remember that most anything you do for room treatment, on some level, will help improve it.

You also want to make sure that the distance between your mons, the outside walls and your ears, create the perfect triangle about 3 to 4 feet behind your listing position, as well as having your mons at the height your ears will be at when you are sitting. This information will self destruct in:
 
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Hi, and thanks for the reply!

I certainly use the room more for mixing so that's great advice.

If I were setting my room up for mixing with 4 small bass trap panels, do you think it would be better to have 1 trap in each top corner, or 2 in the front wall corners?
 
Hello Mack, and thanks for this detailed response!

I really appreciate the advice, and it's nice to see some fresh ideas about cheap treatment. I haven't come across the pipe booth idea before.
Thanks for encouragement not to overspend too!

Regarding your suggestions for room treatment, you mentioned using a bookcase along the front wall, and also putting up traps on the front wall corners along with a drape of some sort.
Which do you think would be the best option?

If I put bass traps on the front wall corners with a drape in the middle, would the bookcase set up work for the back wall too?
 
I'd advise not to cut the panels, double up two sets of 2, hang them with hooks in the back corners as you have though, and experiment with placement - maybe a few inches down from the top corners will be best, you won't know until you try. The 5th one as a cloud.
 
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Can you get hold of glassfibre?

Not nice stuff to handle I know but you can leave it sealed in its plastic bag for bass trapping.

Dave.
 
Ytakary said:
Regarding your suggestions for room treatment, you mentioned using a bookcase along the front wall, and also putting up traps on the front wall corners along with a drape of some sort. Which do you think would be the best option?
Click to expand...

Sorry for the confusion. You would want the book case on the wall that your mons are facing. Even if this is not the FIRST point of reflection, by the time the sound waves hit the book shelf, they will be diffused BEFORE they start heading your way.

By placing your bass traps on the wall BEHIND your mons, since the original sound that came out your mons, has already bounced off the side walls floor and ceiling, than into the book shelf where it will get diffused, and than bounces off your side walls, floor and ceiling on the return trip back towards you, some of the energy will have been removed, before it hits your bass traps, and than gets reflected back to you at your listening position.

This process happens about a billion times a second. @mjbphotos made a very good point about placement. You need to move them up and down to find that sweet spot.

If I put bass traps on the front wall corners with a drape in the middle, would the bookcase set up work for the back wall too?
Click to expand...

Absolutely. Remember that sound travels something like one mile per 4.9 secs. Now think about how fast it is ripping through your room. As the sound goes on its merry way, every time it reflects off of hard services, it will get slower and the sound pressure will get weaker as well.

Like we have already established, this is just some things we all can do to help improve our rooms, but it is by no means, a process that will allow us to compete with the "Big Boys" who have built in every safeguard to keep their area as flat and soundproofed as possible. Now, if you are really strapped for money, I sell portable sound booths for $99.95 that will fit in your room perfectly.

I will even ship it to you free of charge, just to help you out. If you are good with drawings as well as a few tools, I will give you permission and waive my copyright so you can build your own. You can click here to view all the details as well as how it will improve your sound, the instant you start to use it. NYKTF!
 
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ecc83 said:
Woah! Hang on Mack! You can't SLOW sound down in air! Dave.
Click to expand...

Why not? Science once taught that it was impossible to slow down the speed of light. That has now been disproved. Now please keep in mind that I do not believe you can bring sound waves to a screeching halt, but it is possible to slow it down. I got this information by someone who is know worldwide for his "out of the box" thinking when it comes to sound treatment.

The example I gave above, is just to illustrate that any improvements you can make, regardless of how small they may be, will produce cleaner audio. It is kinda like how air diffusion works for your ac vents. Build a box that forces the air to make 3 or 4 90 degree turns and line the box with audio absorbing material.

The air has no problem making the turns but the noise that is transferred within the air from the blower, will have a harder time making the turns. As it was explained to me, the sound hits the first wall, slows down, goes to the next 90 degree turn, slows down and so on. As it is doing this, the sound adsorbing material is reducing the noise as well.

I could be 100% incorrect as I have no scientific proof but I do know what the end results are, as I built two of these boxes last month and they work great for my track room. When I placed my SM 57 24 inches from the vent, the dbs were decreased by close to 40dbs. FYI, this is without any other treatment in a 100% bare room.

EDIT:

Hey Dave, when I come back and edit my position on something, that someone may agree with or disagree with, it is not due to proving anyone wrong or right. It simply has to do with my desire to not provide false information. Sometimes I may, but is only because I took someone advice that I thought was correct. Now, back to my "scientific proof". The illustration below does in fact show that sound can travel at different speeds and therefor be slowed down depending on the medium it is travailing through. In our case, air.

View attachment 100776
 
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You could be getting confused with the isothermal behaviour of sound in a sealed, lagged speaker enclosure?

In that SPECIFIC closed system the speed does indeed drop and makes system resonance lower than it would otherwise be. In an open system, no dice. Now, if we could breath Krypton!

Dave.
 
ecc83 said:
You could be getting confused with the isothermal behaviour of sound in a sealed, lagged speaker enclosure?

In that SPECIFIC closed system the speed does indeed drop and makes system resonance lower than it would otherwise be. In an open system, no dice. Now, if we could breath Krypton!

Dave.
Click to expand...

Well, these days it don't take much to confuse me, :confused: but let me ask you this. Dealing with your last post, is this why they suggest that if you are building a new studio, you should build enclosures at ear level and line them with acoustic foam, to recess your mons in to help deal with resonance?
 
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Thanks for the clarification, Mack.

That's great information to work with. I'll have a play with my bass traps and see how things go and get back to you on the offer.

Thanks again!
 
mjbphotos said:
I'd advise not to cut the panels, double up two sets of 2, hang them with hooks in the back corners as you have though, and experiement wiht placement - maybe a few inches down from the top corners ill be best, you won't know until you try. The 5th one as a cloud.
Click to expand...

Thanks for the advice! That would make things easier.
 
Mack Caster said:
Well, these days it don't take much to confuse me, :confused: but let me ask you this. Dealing with your last post, is this why they suggest that if you are building a new studio, you should build enclosures at ear level and line them with acoustic foam, to recess your mons in to help deal with resonance?
Click to expand...

Dunno! Seems like a recipe for all sorts of boxy squawkings to me. Got any pics? There is the 'soffit' principle that eliminates speaker/room boundary issues but of course cannot be used for nearfields.

There is a good article in SoS about studio acoustics, must see if I can find it..

Dave.
 
Mack Caster said:
Why not? Science once taught that it was impossible to slow down the speed of light. That has now been disproved. Now please keep in mind that I do not believe you can bring sound waves to a screeching halt, but it is possible to slow it down. I got this information by someone who is know worldwide for his "out of the box" thinking when it comes to sound treatment.

The example I gave above, is just to illustrate that any improvements you can make, regardless of how small they may be, will produce cleaner audio. It is kinda like how air diffusion works for your ac vents. Build a box that forces the air to make 3 or 4 90 degree turns and line the box with audio absorbing material.

The air has no problem making the turns but the noise that is transferred within the air from the blower, will have a harder time making the turns. As it was explained to me, the sound hits the first wall, slows down, goes to the next 90 degree turn, slows down and so on. As it is doing this, the sound adsorbing material is reducing the noise as well.

I could be 100% incorrect as I have no scientific proof but I do know what the end results are, as I built two of these boxes last month and they work great for my track room. When I placed my SM 57 24 inches from the vent, the dbs were decreased by close to 40dbs. FYI, this is without any other treatment in a 100% bare room.

EDIT:

Hey Dave, when I come back and edit my position on something, that someone may agree with or disagree with, it is not due to proving anyone wrong or right. It simply has to do with my desire to not provide false information. Sometimes I may, but is only because I took someone advice that I thought was correct. Now, back to my "scientific proof". The illustration below does in fact show that sound can travel at different speeds and therefor be slowed down depending on the medium it is travailing through. In our case, air.

View attachment 100776
Click to expand...

Nope, that just bad physics. You can't slow sound down, but you can force it to travel a longer path, making it slower than a direct path. It will travel slower thru a thicker medium of course, but you will not slow down the speed of sound in air except, as in your illustration (which is physically impossible to do in a studio environment) by changing the medium (in this case air) itself - temperature and humidity, for example.
 
mjbphotos said:
Nope, that just bad physics. You can't slow sound down, but you can force it to travel a longer path, making it slower than a direct path. It will travel slower thru a thicker medium of course, but you will not slow down the speed of sound in air except, as in your illustration (which is physically impossible to do in a studio environment) by changing the medium (in this case air) itself - temperature and humidity, for example.
Click to expand...

Just PM me the links to back up your statement. If not, we are just wasting each others time. Sound can in fact be slowed down and you have your response above, reversed. Water is much thicker/denser that air, yet sound travels 4 times faster through it. Hot air traveling at a constant speed will be slowed down if it collides with cold air. Again, the speed of sound can in fact be slowed down. Since the OP has stated he is satisfied with the advice he was given, I am moving off this thread. If he request further assistance and asks me for any other advice/opinions, I will do what I can.
 
Mark - I don't have send you links, it's basic physics. (Go check ut a book on physics from your local library.) The speed of sound is determined by the physical conditions of the medium - density and temperature.
Yes, I reversed my statement - sound moves faster through denser medium (to a point), Not sure what yoru hot air hitting cold air statement has to do with sound.
 
mjbphotos said:
Mark - I don't have send you links, it's basic physics. (Go check ut a book on physics from your local library.) The speed of sound is determined by the physical conditions of the medium - density and temperature.
Yes, I reversed my statement - sound moves faster through denser medium (to a point), Not sure what yoru hot air hitting cold air statement has to do with sound.
Click to expand...

Sound cannot move faster than the 'mean particle velocity' of the medium and for air at 20C that is about 340m/Sec. End of.

Dave.
 
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