Speaker/Room calibration

[Mark Seaton]

Here is my baseline and set-up.

Speaker controls at default
Repositioned my speakers to the "Golden Process" on the EA website. Rule of thirds not feasible.
New Speaker position - from side wall to center of speaker - 44.7" (was 36")
New Speaker position - from front wall to front of speaker - 72.4" (was 66")
New Sitting position ~ 78-84".. just past the triangle and about 118" (was ~84") from back wall

Measured 20Hz - 200Hz, no smoothing

Overlay =
Green tracing is mic 4' 6" from back wall
Gold tracing is mic at new seating position ~118" from back wall

Looking Good!

Edit: just took a quick listen... all I can say is Holy Crap!!

Hi Bruce,

Entertaining, and busy thread here. I took a little time to skim and catch up last night, and took a quick stab at a simplified model to see if it tracked the peaks/dips. With some tinkering after a modeled curve that looked related, I'd be curious to see a measurement like the above at the following listener + speaker location:

Keep listening position 118" from back wall as above.
Keep same ~45" from side walls.
Slide speakers closer to front wall such that front center of woofer/baffle is 57" from front wall.

I suspect this will tame down the 55-75Hz range. The location might not work overall, but I'd be curious if the changes follow what I'm guessing.

For the few wondering if the recessions in the response are really all that audible, I would argue they are highly audible, especially for mixing. After the bass range I'd then set the sights on the 80-300Hz range.

I suspect the 3kHz dip is related to listening height vs. tweeter height as that will impact the integration of the mids & tweeter at the listening position. Try taking another comparative measurement to the one below while moving the mic down to within the height of the tweeter:

Also remember that you can do some experimenting to check what dimensions are responsible for different effects by moving the microphone in a single axis rather than heavy speakers (especially vertically!).

 

[rbbert]

..And regarding the triangulation; I never mentioned "equilateral".

Perhaps not, but here is the original quote from Mitch

"I found setting up my equilateral triangle to be a critical factor in the reproduction of the soundstage"

 

[NorthStar]

Perhaps not, but here is the original quote from Mitch

"I found setting up my equilateral triangle to be a critical factor in the reproduction of the soundstage"

I'm not sure but I believe it was a way of speech perhaps.
Mitch knows best. And particularly in his own room.

* Equilateral is good; 60 degree angles.
9' x 9' x 9'; I tried it before and it was 'spacious',
as in a very pleasant & realistic soundstage, with great imaging. :b
I bet few music recording/mixing engineers adhere to that too.

 

[Bruce B]

So far I've gotten the best results with toe-in meeting about 18-24" behind my head. Right now I'm sitting just outside the triangle. I've lowered my chair and my ear sits at 37" from floor. Remember guys, I have a big mastering console in front of me. I'll shoot the new graphs at this height as well.

Thanks so much Mark for the suggestions. I'll certainly work them into my next measuring session.

 

[RBFC]

I'm waiting for the first suggestion to come in & ask you to cut a channel in your console for proper tweeter height exposure.....

Lee

 

[Bruce B]

I'm waiting for the first suggestion to come in & ask you to cut a channel in your console for proper tweeter height exposure.....
Lee

I had the console custom made for me with the corners and angles designed to have the least impact on the sound. It is designed to work as a bass trap, as best I could have it built. It's only 30" high at it's peak.

 

[RBFC]

Bruce,

Your room is beautiful. The planning and execution are incredible. I am simply marveling at how the members are getting you to push 500# speakers around, etc. It's like having your wife suggest spots for the new furniture!

It is, however, a valuable learning experience.

Lee

 

[Ron Party]

Furniture mover sliders work great.

 

[NorthStar]

For 530 pounds? You need rolling platforms for that Ron,
and even then, you still have to push or pull.

Oui monsieur?

 

[Mitchco]

Re: equilateral triangle

The studios I worked in have the control room monitors configured in an equilateral triangle. I posted a few pics of control rooms with room treatment a few posts back. If you look, you will see that they are set up as an equilateral triangle. If you search online, this is the standard way to set up monitors. For example, http://www.sweetwater.com/shop/studio/studio-monitors/buying-guide.php

Plus you can see a few equilateral triangle layouts here: http://www.computeraudiophile.com/blogs/Hear-music-way-it-was-intended-be-reproduced-part-2

I can’t find the stereo spec at the moment, but it is the same as the front 2 channels in the 5.1 music mixing guidelines from Dolby Labs: http://www.dolby.com/uploadedFiles/.../Professional/4_Multichannel_Music_Mixing.pdf

This is how it is done in the control room in studios. I want to hear music reproduced as if I was sitting in the mixing chair. The first place to start is setting up your listening position and speakers in an equilateral triangle to get the image the same as it was mixed in the studio. The mixes I made in the studio translate perfect in my listening room with the same equilateral triangle.

My point with the distance laser measurer is to ensure you have the triangle setup to within 1/16” to ¼” tolerance. Not only in the triangle, but also symmetrically with the same tolerance to the rear and side walls. That is what I meant by critical.

 

[NorthStar]

Re: equilateral triangle

The studios I worked in have the control room monitors configured in an equilateral triangle. I posted a few pics of control rooms with room treatment a few posts back. If you look, you will see that they are set up as an equilateral triangle. If you search online, this is the standard way to set up monitors. For example, http://www.sweetwater.com/shop/studio/studio-monitors/buying-guide.php

Plus you can see a few equilateral triangle layouts here: http://www.computeraudiophile.com/blogs/Hear-music-way-it-was-intended-be-reproduced-part-2

I can’t find the stereo spec at the moment, but it is the same as the front 2 channels in the 5.1 music mixing guidelines from Dolby Labs: http://www.dolby.com/uploadedFiles/.../Professional/4_Multichannel_Music_Mixing.pdf

This is how it is done in the control room in studios. I want to hear music reproduced as if I was sitting in the mixing chair. The first place to start is setting up your listening position and speakers in an equilateral triangle to get the image the same as it was mixed in the studio. The mixes I made in the studio translate perfect in my listening room with the same equilateral triangle.

My point with the distance laser measurer is to ensure you have the triangle setup to within 1/16” to ¼” tolerance. Not only in the triangle, but also symmetrically with the same tolerance to the rear and side walls. That is what I meant by critical.

I agree 100% with you Mitch, and I knew that already. Thanks!

P.S. Sorry for quoting you, but we just started a new page, and wanted to be clear.

 

[Mitchco]

I can’t find the stereo spec at the moment, but it is the same as the front 2 channels in the 5.1 music mixing guidelines from Dolby Labs: http://www.dolby.com/uploadedFiles/.../Professional/4_Multichannel_Music_Mixing.pdf

To follow up, here is the stereo spec for the equilateral triangle (See Annex 1):

RECOMMENDATION ITU-R BS.775-1* MULTICHANNEL STEREOPHONIC SOUND SYSTEM WITH AND WITHOUT ACCOMPANYING PICTURE

http://www.gearslutz.com/board/atta...800d1305311642-sticky-links-itu-r-bs775-1.pdf

 

[Bruce B]

To follow up, here is the stereo spec for the equilateral triangle (See Annex 1):

RECOMMENDATION ITU-R BS.775-1* MULTICHANNEL STEREOPHONIC SOUND SYSTEM WITH AND WITHOUT ACCOMPANYING PICTURE

http://www.gearslutz.com/board/atta...800d1305311642-sticky-links-itu-r-bs775-1.pdf

Our Post control room is an ITU certified 5.1 surround room. We use Focal professional monitors in there.

 

[treitz3]

Hello, Bruce. Have you by chance made any headway yet?

 

[Bruce B]

Hello, Bruce. Have you by chance made any headway yet?

Not too much... I have mastering projects coming in, and everytime I move the speakers, I have to get my ears calibrated to the new position. So I can't do too much at this time until I catch up on all these projects and have a few days were I can experiment again. Thanks for checking in though!

 

[treitz3]

Trust me, I am one who understands completely. Take your time and thank you.

Enjoy the music!

 

[Bruce B]

I've decided to throw a monkey wrench into the mix.... so to speak. Since I got the big MM3 speakers, I've had to be careful how I opened doors and such. Everytime I needed to move a piece of equipment in and out of the room, I've had to move the speakers. Also, when I had clients during an attended mastering session, I've always wished the doors were in the rear of the room instead of the front. Well I got to thinking one night and wondering if I could rotate my room 180 degrees! I called the designer and searched the internet and low and behold, the room was actually designed as a 5.1/recording area. If I rotated everything around, all the angles would coincide with a proper 2-channel listening room!
So the week of Apr 30th, I will be tearing down all the equipment in my room and rotating the layout 180 degrees. The designer has given me drawings where everything should be. This is a major undertaking and I'm so thankful that this room has the flexibility to do this with out too much interruption. Wish me luck!!

 

[jpv]

Bruce,
Back to square one.

 

[NorthStar]

I've decided to throw a monkey wrench into the mix.... so to speak. Since I got the big MM3 speakers, I've had to be careful how I opened doors and such. Everytime I needed to move a piece of equipment in and out of the room, I've had to move the speakers. Also, when I had clients during an attended mastering session, I've always wished the doors were in the rear of the room instead of the front. Well I got to thinking one night and wondering if I could rotate my room 180 degrees! I called the designer and searched the internet and low and behold, the room was actually designed as a 5.1/recording area. If I rotated everything around, all the angles would coincide with a proper 2-channel listening room!
So the week of Apr 30th, I will be tearing down all the equipment in my room and rotating the layout 180 degrees. The designer has given me drawings where everything should be. This is a major undertaking and I'm so thankful that this room has the flexibility to do this with out too much interruption. Wish me luck!!

Good luck!! :b

 

[RBFC]

Websters Dictionary:

Glutton for Punishment: (def) Bruce Brown, one who enjoys inflicting punishment upon himself

Let us know how it "turns out", Bruce! Good luck!

Lee