Room acoutsics?

[chris hansen]

Hi,

I moved my congas into a corner of the basement and it sounded different. I tried hanging up a sweatshirt on the wall and it sounded a little better so I was thinking of getting some blankets or sheets to hang on the walls. Would that work? Do you do anything to improve the acoustics of your practice roo.?

[109-1176549166]

Hi Chris,

Other than being a multi-percussionist, I also have a small sound system rental business and often get hired as the FOH (front-of-house) and/or monitor soundman as well for band gigs or small-to-medium-sized concerts that rent my system.

Placing your congas into the corner of a room will usually add boominess (natural bass) and reflection (natural reverb) to their sound. When you hanged the sweatshirt on the wall, you reduced some of the reflectiveness of the wall nearest your congas. Therefore, they sounded more natural or "better" as you put it.

Recording studios place sound-deadening foams on the walls to kill any artificial coloration to the sound of the instrument(s) added by soundwaves bouncing off of walls, particularly those made of hard materials. The objective is to hear, capture and record the pure sound of the instrument(s) as possible without any added color to the its/their sound.

So, regarding what you should do, the bottom line to me is this: It depends on the quality and volume of sound you want to hear from your congas in your practice room: Whether you want (1) no added coloration at all, (2) some added coloration or (3) just as it is. And depending on the materials on the walls of your basement, Option #1 will obviously be the most expensive.

Personally, I don't care that much about how the room materials affect the sound of my instruments when I'm practicing. (The only time it really matters is when I'm doing a recording or, perhaps, demonstrating the sound of my instruments to clients.) Why? Because I know that when I get to do live gigs, I'll have no control over the natural acoustic properties of the venue--closed or open air--anyway and my instruments will inevitably sound different, unless they're properly EQ'd.

In live gigs, to get the sound I want from my multi-percussion instruments (congas, bongos, timbales, percussion toys & Roland HPD-15), I'll always fall back on my own EQ'ing on my submixer and the EQ'ing on the main mixer by the FOH and/or monitor soundman, if any, other than myself.

Hope this helps,



Edited By mjtuazon on 1184101937

[chris hansen]

Hi Chris,

So, regarding what you should do, the bottom line to me is this: It depends on the quality and volume of sound you want to hear from your congas in your practice room: Whether you want (1) no added coloration at all, (2) some added coloration or (3) just as it is. And depending on the materials on the walls of your basement, Option #1 will obviously be the most expensive.

Thanks for the reply.

I think I'd prefer option 1. I spend most of my playing time in the basement so it would be nice if it sounds good and there's no reason it has to be louder than necessary.

Is there a budget option for sound deadening? Could I just get a couple of cheap bedsheets or something?

[jorge]

Unfortunately, making a room uncolored soundwise is usually a big expensive project that only works for large rooms. Sheets, blankets, carpet, egg crates, thin (less than 2 inches thick) acoustic foam absorb only mid and high frequency sounds (they color the sound). Low frequencies pass right through thin absorbers and you still have uneven loudness for your bass frequencies. Thin absorbers like sheets or blankets will stop the worst slap echoes between flat parallel walls but usually make the room sound boxy. If your problem is mainly slap echoes (clap your hands and you hear a few echoes before they fade away), this might be enough.

Depending on the size of your room, there are several ways you can improve the acoustics of the room enough to have rehearsals or do recording in the room. Small rooms (volume = length x width x height less than 1500 cubic feet) virtually always have terrible acoustics, with very uneven sound especially in the low frequencies. Small usually means a room less than about 12x16 with 8 foot ceilings. For practicing only the acoustics are usually not a big problem. For recording or rehearsing with a group, it would be good to put in some broadband absorption that would absorb low as well as mid and high frequency sounds. Every room is different and your needs depend on the geometry, furniture, and wall/ceiling/floor materials of the room. Low frequency sounds have wavelengths of 4 feet to 25 feet, and broadband sound absorbing material needs to be at least 4 or 6 inches thick to have any noticeable effect. How many 2 ft x 4 ft x 4 inch thick slabs of rockwool or fiberglass sound absorbing material you need depends on the the specifics of your room. The most efficient way to improve the room acoustics is to put the absorbing material across the corners of the room, ie all the wall/wall vertical corners and maybe some wall/ceiling corners. Also, a big soft upholstered couch can absorb a lot of low frequency sound.

For details, I suggest looking at websites such as

http://forum.studiotips.com/
or
http://www.johnlsayers.com/phpBB2/index.php

Good books on room acoustics for non-engineers are:
Master Handbook of Acoustics by F. Alton Everest (a classic)
or
Home Recording Studio Construction: build it like the pros by Rod Gervais.

Although you did not say you want a recording studio, the acoustics principles are the same for a rehearsal space and these books explain the concepts clearly with lots of practical information.

You could also buy ready made bass traps like ReadyTraps www.realtraps.com, although that would be more expensive than making your own sound absorption.



Edited By jorge on 1184174336

[Tonio]

Kudos Jorge,
I see you have been researching/studying acoustics.

I have been on that road for about 2 years while learning about recording and mixing. I'm glad someone on this board I can share info with finally !!

I have a small dual purpose room(tracking and mixing). Which is almost futile in general as you may know.

I have made acoustical treatments and have re-tweeked several times. At this point I have quite a few bass traps with rockwool 4" 4.5 PCF density on corners and ceiling /wall junctions. Also a few reflection free zone 2" 703. And 2 large clouds.

Its getting tight and to the point that mixing is no problem, but some ambiance have been compromised-especially the more acoustic style us congueros are involved with.

At any rate, I agree if a neutral sound is preffered the room is the most dominant factor of getting a good sound more so for recording. Rehearsal .. hmm well its more about how much you can tolerate before considering acoustical treatment. In small rooms the low end is the monster, but adding in too much mid & high frequency treatment can kill all the ambiance you may want. I have created mostly broad band absorbers to have high frequency reflections to keep it alive.

Diffusion may help in larger rooms, which have a source distance of 20 feet or more. A simple poly can helpp scatter the mid/high end for a cleaner ambiance.

T

[109-1176549166]

Jorge,

Great information, especially the website links and book references.

Thanks mucho for sharing!

[Tonio]

Although you did not say you want a recording studio, the acoustics principles are the same for a rehearsal space and these books explain the concepts clearly with lots of practical information.

I may have to disagree here to an extent. Tracking rooms need a more live aspect and the RT60 should be alittle longer-say about .2 ~.4 ms for good sounding drums. Of course its should slope downward in time (from low to high freq).

Just nit picking

T

[chris hansen]

For details, I suggest looking at websites such as

http://forum.studiotips.com/
or
http://www.johnlsayers.com/phpBB2/index.php

I looked at the links and wow! I guess I'm just looking for a simple way to tone it down a little. It can be far from perfect and I'm sure I'll be happy.

Would it help just to look for some cheap polar fleece blankets to hang on some walls?

[109-1176549166]

Chris,

I guess that the lesson here again is that sometimes you have to be careful about what you ask 'cause you don't know what'll you get. :;): ???

But, I'm sure that all responses that you've received are totally well-intended.

Kidding aside, I agree with you. Just be practical.



Edited By mjtuazon on 1184188314

[jorge]

Hi Chris,
I understand that you want a quick and easy solution here. What Tonio and Mjtuazon have said is helpful, but we have had to give you very general answers. We could be more specific and helpful if you give us a little more information about your room.

1) How big is your room, including ceiling height?

2) What are the walls, floor, ceiling made of?

3) Do you play by yourself or will others be playing congas in the room as well?

4) Furniture or carpets in the room?

5) Just congas, or will you be playing along with recorded music over a stereo?

6) What is your approximate budget?

7) What don't you like about the sound of your congas in the room as it is now?

Jorge