Help create open voice booth on one corner of a room

singerRecorder

New member
Hi all ! First of all, thank you so much to everyone who is so helpful on this site.

After reading so much though, I feel I am getting very confused, and I haven't read anything that's quite my situation. So here goes :

I need to create a space where I can record vocals. No instrument, nothing, only a singer facing a mic.

I have this room in my house that also needs to serve as an office. I have tried recording on it, and it's terrible because walls are concrete on one side, plasterboard on the other, with no acoustic treatment whatsoever. So the echo is terrible.

I need to treat the room so that there is much less echo.

My current idea is to make the bottom left corner of the room a sort of open voice booth. I have low DIY skills, so I am trying to go for a simple solution.
My plan is to buy two bass traps, one on the corner in the floor, one on the corner in the ceiling (found some at like 15 GBP on amazon)
Then put 2 or 3 plaques of acoustic panels on each of the 2 walls, close to the corner (found some packs not too expensive on amazon)
I also use a semi-sphere of foam directly placed on the mic stand (though I am not sure how much this helps).

Does that make any sense ? Is it just hopeless to leave everything else untreated ? I could probably put more acoustic panels on the other walls, but I hear that bass traps are the most important, and I think it will become very unsightly for the office to have too many bass traps.

Is there a better idea ?

Thanks !
 

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I would offer that for a given amount of panels 1" fiber -not foam min, 2 or more inches better, you are always better hanging or mounting them around you and the mic -away from a corner.
Three sides of the typical 2'x4' for example up and relatively close around you can do a lot. One above if you can manage it tackles the remaining worst close hard reflection (unless you have quite high ceilings.
I've done temporary setups hanging them off mic stands for example then raising them up to get an effective height.
 
Hey, thanks for your help !

My ceilings are 2m60 high (8.5 foot). Is that high enough you think ?

Just to make sure I understand, it sounds like you are advising me not to put the acoustic panels on the wall, but actually to create a small box around the mike. Is that correct ? I bought a small vocal booth that attaches to the mic. It is half a circle of acoustic material, but I found it didn't make much of a difference.
 
If it is just vocals, a good broad-band trap will work, but as [MENTION=39487]mjbphotos[/MENTION] and [MENTION=115145]mixit[/MENTION] have posted, you need "real" acoustic panels, not pieces of foam.

The key is to reduce the reflections entering the microphone so the sound of your voice is so much louder that they do not degrade the quality of that, and also to the point that they are not still bouncing into the mic when you are silent. So first you look at the microphone pattern - should be cardioid, not hyper/super IMO/IME, and realize that it's "hearing" everything that enters that pattern. I'd start with covering sides and part of the ceiling (with "clouds"), say 60 to 90-degrees from the mic, so the immediate reflections from your voice off those surfaces (imagine pool/billiards bank shots) are well-trapped and do not come in to mix with your voice. These are really the most important ones. The area right behind you, i.e., the corner, should be treated as well to capture stuff that is coming back from reflecting off other surfaces in the room. Those sounds will be diminished by the length of travel, but that particular direction is going to be the area of most [mic] sensitivity, plus the extra delay creates a lot of the "in-a-box" sound, and is what will trail into the silent parts.
 
The graph doesn't look horrible, but if you expect to record baritone or lower vocals you probably want something a little denser or thicker.

I attached a couple plots of 2" OC703 (unfaced) and the GIK 2" panel, which I believer are made from one of the OC703 flavors. You can see that they also start to drop off below 400Hz. If you need more low frequency control in the room, you'll want to look at thicker/denser material, or ones called bass traps.

2inAbsorbCoef.png

P.S. To show how density improves bass absorption, here's 3" OC703 and Rockwool Safe'n'Sound plots.They start out better at 125Hz and increase more rapidly. You can see OC703 specs here:
https://dcpd6wotaa0mb.cloudfront.ne...lation-Product-Data-Sheet.pdf?v=1582773799000

Screen Shot 2020-04-11 at 4.14.58 PM.png
 
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Thanks for that, that's really useful. I ended up buying bass traps. I read online that voice frequency is 80 Hz to 180 Hz, so it seemed indeed the most important part of the spectrum.
 
Thanks for that, that's really useful. I ended up buying bass traps. I read online that voice frequency is 80 Hz to 180 Hz, so it seemed indeed the most important part of the spectrum.

That's like the low E on a guitar, up to not-quite middle C. Voices can go a lot higher, and it s the harmonic content that makes a voice sound like it does.
 
Thanks for that, that's really useful. I ended up buying bass traps. I read online that voice frequency is 80 Hz to 180 Hz, so it seemed indeed the most important part of the spectrum.
That's like the low E on a guitar, up to not-quite middle C. Voices can go a lot higher, and it s the harmonic content that makes a voice sound like it does.
Yeah, what [MENTION=39487]mjbphotos[/MENTION] said. That's really the very bottom of the bass[o] range, not your typical singer. Unless it's a bass voice (like I noted earlier), broadband trapping is probably enough. Bass traps, assuming made from the same material, tend to be just bigger and thicker, often tall for corner applications. But, if you got flat panels, they will also be quite effective for use on the sides and overhead for early reflections, so long as they can be safely mounted.

And, with the same cautions we harp on over and over here, just because something claims to be acoustic treatment or a bass trap, and is covered in black (or red!) fabric and looks good, doesn't mean it's actually effective. Knowing the material and specs are important.

Let us know how it works once you get it and try it out. Post pictures, recordings!
 
Thanks that all makes sense. In my specific case, most of what I will record are a male voice, just talking. So I think it will stay in the low ranges. have purchased bass traps that have a coefficient of noise reduction above 1 across the spectrum. So it seems pretty good and fairly cheap (downside is that it's 30 cm thick, and really only goes in corners. It would be good if I found a broadband trap that is in the form of a panel, to hang on the wall, but I haven't found one that has a coefficient of noise reduction above 1 at the low frequency.

So I'll start testing with just the bass traps when I receive them and see how it goes.
 
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