2. Yes I was in the room however I swear I never made a sound.
Sometimes just being in the room can make a difference, but not usually as big as is evident here. But using the "start delay" should get rid of that. Set it to a delay long enough for you to be able to get out of the room and close the door, plus another few seconds for things to calm down inside. Also set "Sweeps" to "2". That means that REW will run two sweeps for each test, then take the average. That helps to improve the signal-to-noise ratio as well.
please go to ... for all to see my control room and tracking
Mackie 32.8 with meter bridge!
:thu: I love that console. I use a 24.8 regularly. Nice!
Please also post a few up-to-date photos here on the forum, for the same reason as above: in the future, your web site might be at a different location, so the link you posted might not work, thus making it inaccessible to others in the future who might want to follow your thread.
Also, I'd like to see photos of the sides, rear, and ceiling of your room, so I can get a better idea of how it is working right now.
3. I did have my SPL meter set to "C" weighting but "Fast" so I will change that REW was "C" weighted and "Slow"
REW is set to "C" and "Slow" by default, but it's worth checking, as you might have changed it by accident.
But are you SURE you calibrated REW to your meter: You really did tell REW what the real level is when you did the calibration, right? You typed that into the box and hit "enter", then checked that the level on your meter matched what the REW calibrator window was telling you?
If you don't tell REW what the real measured level was in the room, then it has no way of knowing...
4. When I tool the measurements of both speakers the measurement was higher than when I did Left and Right speakers.
Correct. The level should increase by 6 dB, from 80 for each individual speaker to 86 for both at once. That's why studios are calibrated at 86 dB... REW uses coherent sine sweeps for the test signal, so it sums to exactly twice the intensity, thus giving you an increase of exactly 6 dB.
5. Also, when the first measurement was taken I only had -1.3db headroom left. Previously to that when I took the measurements REW said there was clipping
.:: which makes me suspect that you have too much gain at some point in your signal chain, and not enough at other points. Are you going through your Mackie console? If so, make sure that the output level from your DAW really is at -12 dB on the channel meter on the console when the speakers are producing 80 dB each, and that the meter on the channel you are using for your ECM8000 peaks no higher than 0 dB when you are playing the calibration test signal (pink noise). Then set your sound card interface accordingly. If you set up your gain structure correctly, there should be plenty of head-room: at least 10 dB. Make sure you have the EQ button for those channels turned off on the channel strips, and that the output channels are panned hard left and hard right, while the mic input channel is panned dead center.
so what do you suggest as my system in terms of mic input volume and speaker output is at maximum without clipping...?
The goal is to have the entire signal chain calibrated to 0 dB when the test signal is playing, and adjust the speaker volume controls to get 80 dB(C) SPL from each speaker (which will automatically be 86 dB(C) SPL) with both speakers playing). The second goal is to have your ECM8000 input channel gain set such that the meter is showing 0 dB when you have both speakers producing 86 dB(C) SPL, and your interface gain controls set the same. If everything is showing 0 dB while the speakers are playing individually, then you will not have clipping.
6. My DynAudios are set to "flat" response, and 0 db
And you are not using a sub, correct?
7. The whole studio including control room is John's inside outside design
Ahhh! OK, that explains it. That's fine then. With that approach, the idea is to start with the dead space then add treatment to liven it up selectively. That's the opposite of what you do for conventional construction: starting with a very live reverberant space, then adding to treatment to deaden it. I prefer John's approach, and I do that whenever I can. So that's fine: At least I now understand where you are coming from, adn the reason for the deadness.
Control room has John's soffit mounted speaker design with bass hangers underneath and all corners have bass hangers.
Great! What I was thinking was a lack of bass trapping is actually a lack of mids- and highs-. The room is bigger than it seems from the graphs, and since I wasn't aware that it was built inside-out, I was making the wrong assumptions. What we need to do is to liven up the mids and highs. Highs are easy, mids not so much...
The thing that is strange about your data is the lack of bass. I don't get why there's that major roll-off in bass levels below 120 Hz. Your BM6A's are capable of better than that, which is why I was wondering if you maybe had the controls set wrong. What else is there in the signal path that could be rolling off the low end? Do you have any equalization in the signal path? If so, set it flat. What I'm seeing on the graphs is not what I would expect from DynAudio BM6s. Those are great speakers, and they don't roll off at 120 Hz., so it must be something else in the signal path that is killing the low end. Or it might be some artifact of the way the room is set up. Please provide an accurate diagram of the room, especially the positions of the speakers, the mix position, and the major treatment, and showing all the dimensions. As well as the photos!
- Stuart -