Bass Traps for Nasty Mix Position Modes

[analogdiesel]

There are some great threads here on low end control and I've scoured them all to learn quite a bit. However, I have a specific problem that I'd like to address.

The room size is about 10' wide, 12' deep and 7.5' ceiling. When I run a sine sweep, the main problem area is centered around 120hz. Now, the mix position and the couch at the back of the room (about 18" from the rear wall) are the worst areas, where bass loads the most. When I move into corners and side walls, these seems to be null points, as the bass almost disappears in these areas.

So I'm assuming that the corners are where bass is at it's maximum pressure and least velocity (or other way around, not an acoustic expert obviously).

My question is, would corner 'traps' help this problem that exists in the mix position since it seems energy isn't 'loading' in the corners?

Thanks all!

[Glenn Kuras]

My question is, would corner 'traps' help this problem that exists in the mix position since it seems energy isn't 'loading' in the corners?

Bass traps should always go into he corners. Also you want to hit places like the back wall (behind the couch) as there are nasty nulls and peaks coming from that area.

[analogdiesel]

interesting.

thanks glenn! i'll start in corners and back wall with fairly thick absorption. i'm thinking of putting a facing on these (perforated) so as not to suck out a huge range of mid/high frequencies as well.

[Glenn Kuras]

Originally Posted by analogdiesel

interesting.

thanks glenn! i'll start in corners and back wall with fairly thick absorption. i'm thinking of putting a facing on these (perforated) so as not to suck out a huge range of mid/high frequencies as well.

Yep putting facing on them will work kind of like our GIK 244 and Monster. thumbsup
Let us know how it turns out.

[Arksun]

I'm just wondering, would putting less breathable fabric on a basstrap also help to reduce the absorption of higher frequencies, or would that impact its ability to absorb the lower frequencies as well?.

[Glenn Kuras]

Originally Posted by Arksun

I'm just wondering, would putting less breathable fabric on a basstrap also help to reduce the absorption of higher frequencies, or would that impact its ability to absorb the lower frequencies as well?.

You could do it that way also.

[JohnPM]

Originally Posted by Glenn Kuras

Bass traps should always go into he corners.

I guess that might bear some qualification. For the best overall impact, I'd agree, but if dealing with a specific problem it may not be the most efficient use of a given amount of treatment. If the problem is primarily due to a particular axial mode (or group of modes) it would be best to concentrate the treatment to cover as much as possible of the surfaces at the ends of that axis - e.g. if the length modes are the main issue, then covering as much as possible of either the back or front walls (or both) should give you greater improvement in that problem area than putting the same amount of treatment in the corners. Broadly speaking the biggest problems are from the axial modes on the longest axis, so there's merit in making treatment of the back or front wall a higher priority than the corners - the more absorbent those surfaces are the faster the modes will decay and the lower their amplitudes. If the particular problems in a room are mainly due to axial modes then treatments in the corners may prove disappointing as the proportion of the area supporting the mode that is dealt with may be quite small.

[Glenn Kuras]

Originally Posted by JohnPM

I guess that might bear some qualification. For the best overall impact, I'd agree, but if dealing with a specific problem it may not be the most efficient use of a given amount of treatment. If the problem is primarily due to a particular axial mode (or group of modes) it would be best to concentrate the treatment to cover as much as possible of the surfaces at the ends of that axis - e.g. if the length modes are the main issue, then covering as much as possible of either the back or front walls (or both) should give you greater improvement in that problem area than putting the same amount of treatment in the corners. Broadly speaking the biggest problems are from the axial modes on the longest axis, so there's merit in making treatment of the back or front wall a higher priority than the corners - the more absorbent those surfaces are the faster the modes will decay and the lower their amplitudes. If the particular problems in a room are mainly due to axial modes then treatments in the corners may prove disappointing as the proportion of the area supporting the mode that is dealt with may be quite small.

Your right, I was talking more on a starting point. Thanks for CORRECTING ME!!!!!!!!!!