Post by: Gio on July 26, 2008, 11:32:42 AM
Well, after 10 months of fighting to get mixes to sound right in my "home" space, I decided to take some measurements and figure out what the problem is. A day of moving speakers around, and listening position too, has yielded two scenarios that seem viable(but still kind of ugly, each in their own way).
Question: What would be considered a reasonable/ realistic response to aim for, ie: +/- how much from the target level?
The room is about (L)35'5" x (W)12'8" x (H)7'10". The trouble is, the space is divided in half by a stud frame covered with chicken wire, so it is "open", but I have no access to it. (my landlords storage area). I'm not allowed to close it off.
I do have panels around the room (2" & 4" 703), and I only have one corner under the open stairs in which to stuff as much trapping as I can.
Any thoughts would be greatly appreciated, and my apologies if this is a bit long.....
Regards,
Post by: Ethan Winer on July 26, 2008, 12:51:50 PM
| Gio wrote on Sat, 26 July 2008 11:32 |
What would be considered a reasonable/ realistic response to aim for, ie: +/- how much from the target level? |
If you can get the response within a 10 dB window you'll be doing well.
| Quote: |
The room is about (L)35'5" x (W)12'8" x (H)7'10". The trouble is, the space is divided in half by a stud frame covered with chicken wire, so it is "open", but I have no access to it. |
The good news is a long room has fewer bass problems than a short room. The bad news is you can't put bass traps along the rear wall and corners if the landlord won't let you in there. So you'll instead focus more in the front of the room where you can put bass traps.
| Quote: |
I only have one corner under the open stairs in which to stuff as much trapping as I can. |
Most rooms have 12 corners.
--Ethan
Post by: Gio on July 26, 2008, 01:32:12 PM
| Ethan Winer wrote on Sat, 26 July 2008 12:51 |
Most rooms have 12 corners. |
Heh heh! Right! I should say in this case, I have 5 corners.
Here is what it looked like before I started.........
I'll follow with two others.
Post by: Gio on July 26, 2008, 01:34:56 PM
Post by: Gio on July 26, 2008, 01:37:37 PM
Which would you rather work with? " A " kind of hurts to listen to....
Thanks!
Post by: Ethan Winer on July 27, 2008, 12:25:07 PM
--Ethan
Post by: Gio on July 27, 2008, 01:13:27 PM
(these are not NS-10's
)I end up with too much in my mixes from over compensating.
I shot the speaker itself from as close as I could get to it, and it doesn't look like that at all.
Would gobs more 703 do anything to improve that, or am I just wanking here? Or perhaps a sub?
Post by: garret on July 28, 2008, 11:38:51 AM
| Gio wrote on Sun, 27 July 2008 12:13 |
Would gobs more 703 do anything to improve that, or am I just wanking here? Or perhaps a sub? |
What monitors are these? The graph is a little misleading since it goes down to 2Hz. Yeesh, I think only whales can "hear" 2Hz.
But even if you look at the bass range from 50hz to 100Hz, there's very little there. Room modes are probably responsible for the big dips... and you can tame those with bass traps. But unless you set up a monitoring system that has low end, you really can't tame it.
I know some folks who can mix on monitors with no low end by checking the bass on very high quality headphones. But I'm not one of them... Maybe it also depends on the style of music you work on.
I suggest you try a subwoofer, or a higher quality set of monitors that have some low end.
Best,
-Garret
Post by: Gio on July 28, 2008, 11:52:19 AM
Thanks for chiming in. These are a pair of KRK KROKs I "inherited" for the time being. Below is a graph that shows the speaker itself(green trace)measured from about 1" away, and the latest speaker position I got this morning. Each day things improve a teeny bit, but I'd like to get smoother if I can.
Regards,
Post by: Ethan Winer on July 28, 2008, 01:43:00 PM
| Gio wrote on Mon, 28 July 2008 11:52 |
These are a pair of KRK KROKs |
What is their stated -3 dB down point at the low end?
Regardless, adding more bass traps can only make things better.
--Ethan
Post by: Gio on July 29, 2008, 01:03:19 AM
Thanks for your response.
I have two additional questions..
At what res should I be viewing here. Been using 1/6 oct.
Second, as I mentioned earlier, the space has some unique restrictions. The only vertical corner I have to treat is the left one, behind the console, due to doorways,stairs, windows, etc. Would it matter if that one side were stuffed, and the other not?
Regards,
Post by: Ethan Winer on July 29, 2008, 12:47:10 PM
| Gio wrote on Tue, 29 July 2008 01:03 |
At what res should I be viewing here. Been using 1/6 oct. |
For low frequencies I prefer much higher resolution, minimum 12th octave. Since you have REW, just turn off the averaging completely.
| Quote: |
Would it matter if that one side were stuffed, and the other not? |
Symmetry is important, especially in the front of the room. If you can't fit a full bass trap in one of the front corners, can you apply some thinner rigid fiberglass on the door and wall etc to at least match the left and right sides at mid and high frequencies?
--Ethan
Post by: Gio on July 30, 2008, 08:42:29 AM
Let's see what I can get going here!
Regards,
Post by: Gio on September 18, 2008, 09:48:09 PM
Now, what to do about the 200-1k area.........
Post by: Ethan Winer on September 19, 2008, 11:23:47 AM
| Gio wrote on Thu, 18 September 2008 21:48 |
Whadya think? Green trace is when I started, dark trace is where I am now. |
Yes, much better!
| Quote: |
Now, what to do about the 200-1k area |
That may not be as bad as it looks. Above 1 KHz, the measured response often has "phantom" peaks and nulls from reflections off nearby surfaces, and/or due to the different arrival time from two speakers. If you test one speaker at a time and the peaks and nulls get better, then you can ignore the peaks and nulls. Do you have absorption yet at the reflection points? If not, that's the next step.
--Ethan
Post by: franman on September 26, 2008, 02:04:35 PM
Post by: Gio on September 29, 2008, 09:18:07 PM
| franman wrote on Fri, 26 September 2008 14:04 |
I would agree this looks way better.. What did you change? Speaker positioning? Listening position?? The peak just below 1K is almost certainly a reflection caused comb filter as Ethan pointed out.. |
Hi Francis,
Thanks for peeking in. I moved both the speaker and listening positions into the room further, and the listening position is closer to that 38% area. That brought up some low end, ( plus the addition of a few 6" traps). What made a big difference was putting my sofa in front of the console. That big null and peak between 90 and 200Hz flattened out nicely after that!
Almost there I think... Having the speakers on stands has introduced some new anomalies for me, as I'm used to how they sound on the meter bridge. I'm thinking of some sort of diffusion above my head...I have a 703 panel there now. The sweet spot is real narrow, and moving my head just a few inches changes thing quite a bit( hi freq phasey stuff). Would that help scatter things a bit?
Thanks again to Ethan,too!. This has been challenging, but quite the learning experience as well.
Regards,
Post by: franman on October 25, 2008, 06:44:01 PM
I don't suggest diffusion over the listening position in a production environment.. only (possibly) in home theaters or other environments that need spatial enhancement, where you won't be changing the way productions sound!!
Small phasey problems in the top end can sometimes we corrected with very minor adjustments of the final speaker position... balancing out the toe-in, exact distance symetry, etc..
otherwise, you've go an early reflection/comb filtering issue and it needs to be treated with absorption...