Mix position question/uneven ceiling.

[azzzy]

I know that 38% of the length of the room is the ideal spot for mixing for a rectangular room. I assume that's true for a flat/even ceiling. But what if at 50% of the length of the room the ceiling drops a foot? Does that affect the calculation of the ideal mix position? Should I move back a little? Or the ceiling doesn't affect this 38% number?

[Jens Eklund]

http://www.gearslutz.com/board/6449467-post71.html

[azzzy]

Originally Posted by Jens Eklund

http://www.gearslutz.com/board/6449467-post71.html

I am not religiously clinging to any rule. However I do believe that taking in consideration certain rules that came about as a result of acoustic research/experience is a good idea when deciding on one's setup.

[Jens Eklund]

Originally Posted by azzzy

I know that 38% of the length of the room is the ideal spot for mixing for a rectangular room.

Originally Posted by Jens Eklund

Don’t "follow" the "38% rule" since it’s not a "rule", it’s a starting point when searching for a good position in terms of modal coupling.

Try to find this "rule" in any of the serious literature/research. Even if you do, this is only valid assuming untreated, rigid boundaries:

http://www.gearslutz.com/board/6725528-post9.html

[azzzy]

Originally Posted by Jens Eklund

Try to find this "rule" in any of the serious literature/research. Even if you do, this is only valid assuming untreated, rigid boundaries:

http://www.gearslutz.com/board/6725528-post9.html

Well, I am certainly not an expert and can't say that I read anything outside of what's on the internet. However what's on the internet often comes from supposedly respected accousticians and mixing engineers.

Don't get me wrong, I am not defending the 38% rule - I am pretty open-minded about it. In fact if it's not true, I'm happier for it. So... where would you suggest a mix position in a 24' x 24' room with the ceiling that goes from back to front like this: 7' to the middle (12'), then drops to 6' for a length of 8', then goes back to 7' for the remaining 4'? Drywall all around, even doors. I am thinking of placing the mixing console into the space with the lower ceiling and sitting right outside of it (so I would have about 11' behind me and a 7' ceiling). Obviously I will put 4" of mineral fiber on the ceiling above the console and the speakers. I am also making 32" wedges to fill all corners (including the wall/ceiling corners). Would that work?

[DanDan]

That sounds like a reasonable plan.
Don't forget a cloud though.
Establish your speaker and listener positions by measuring acoustically.
Take a look at Thomas Barefoot's Wall Bounce Calculator 2D

Wes Lachot is most likely the source of the 38% analysis.
It too is quite reasonable, as is his 'musical' way of looking at room dimensions
http://weslachot.com/pub7.html

Reasonably Serious,
DD

[azzzy]

Originally Posted by DanDan

That sounds like a reasonable plan.
Don't forget a cloud though.
Establish your speaker and listener positions by measuring acoustically.
Take a look at Thomas Barefoot's Wall Bounce Calculator 2D

Wes Lachot is most likely the source of the 38% analysis.
It too is quite reasonable, as is his 'musical' way of looking at room dimensions
http://weslachot.com/pub7.html

Reasonably Serious,
DD

I'm afraid 6' and 7' ceiling doesn't leave much room for a cloud. But I intend to attach 4" absorbers directly to the ceiling (maybe hang them with a 1" space).

Thanks for the links - will definitely check them out.

[DanDan]

You are welcome. You will probably do a specific cloud, do your best, between yourself and the speakers. You will need to prevent flutter between the floor and ceiling in the rest of the room though. Carpet or rugs, couches, racks.
Be careful with that desk. See Desktop Reflection Revealed thread.
DD

[azzzy]

Originally Posted by DanDan

You are welcome. You will probably do a specific cloud, do your best, between yourself and the speakers. You will need to prevent flutter between the floor and ceiling in the rest of the room though. Carpet or rugs, couches, racks.
Be careful with that desk. See Desktop Reflection Revealed thread.
DD

I plan on covering the entire 8' x 6' area above the console and speakers up to the mix position. I guess that qualifies as a "cloud". Also as far as the rest of the room that will be dealt with as well (somewhat easier though).

Not much I can do about the desk. Can't make it smaller and can't cover it up with insulation. Hm... Perhaps I should make a removable 4" thick insulation to put over the desk after all adjustments are in place to check the mix... An ambitious project for sure but not unrealistic...

[DanDan]

Sounds good. Test for reflection using the technique in that thread, or ETC.
Your desk may have a useful angle already, or maybe you could cause one by putting something under the front legs. Speakers on stands behind the desk can be moved to eliminate the reflection.
DD

[azzzy]

Originally Posted by DanDan

Your desk may have a useful angle already, or maybe you could cause one by putting something under the front legs. Speakers on stands behind the desk can be moved to eliminate the reflection.
DD

I haven't had a chance to read the desk thread yet. There is an angle under which the reflections are minimized?

My console is about 6' x 3.5'. I will have to place speakers on stands anyway because the meter bridge is fairly narrow. I was actually thinking of placing the speakers outside the console as well but that might be too wide.

[DanDan]

The HF aspect of the reflection is most destructive. HF pretty much follows straight lines. Place a mirror on the desk. If you see the tweeter, you have a reflection problem. Moving the speakers or angling the desk will make the image disappear. The reflection will be somewhere else, away from your head.
DD

[azzzy]

Originally Posted by DanDan

The HF aspect of the reflection is most destructive. HF pretty much follows straight lines. Place a mirror on the desk. If you see the tweeter, you have a reflection problem. Moving the speakers or angling the desk will make the image disappear. The reflection will be somewhere else, away from your head.
DD

HF is the most destructive??? I thought it was the LF? Well, either way, a good idea with the mirror. Will do.

[DanDan]

Desktop Reflection Revealed

DD

[azzzy]

Originally Posted by DanDan

Desktop Reflection Revealed

DD

Thanks, I already read it. Good info for sure. When my console is assembled will try the trick with the mirror (for now the console is in a neat pile on the floor ).