Moderators: Aaronw, kendale, John Sayers
That's really good news!
To me, it almost looks like the door was holding the framing in place, rather than the other way around!!!! But at least you got it out and did it right.
You'll probably have to "test and adjust" to get it right, using REW, but for the first approximation I'd suggest 37 Hz, "B" and flat for the highs. Yes, I know you have needed -2 in the past to get your mixes bright enough, but once you get the room treatment in, that will be sucking up the highs like you won't believe, so I'd hazard a guess and say that flat is probably going to where you will likely want it. Also, if you ever decide to do digital tuning (PM me....) then you'll need that flat.Would it be better to have the Low Freq set to 47Hz as well as the Acoustic Space set to A to help compensate for the bass boost of the soffit mount?
I'm looking forward to seeing that! Follow the instructions on the "Aoustics" section of the forum for REW testing...The next two nights will hopefully get the other soffit built the same, so I should be able to REW on Saturday.
Those are probably SBIR artifacts, not modal. To confirm, we can do the "walking mic" test, which is a long and boring process, but reveals a lot about the room... and also the best place to set up your mix position! Let me know if you want to do that, and I'll PM you the instructions.There are two major dips, 83Hz and 135Hz, the 135Hz one is no surprise as the room has two dimensions that are 2.4m.
Yup, but that's sort of like putting a band-aid on a broken bone that is sticking out of your skin... it disguises the ugliness visually, but does nothing at all to actually fix the problem!These tests are with no smoothing - switching some smoothing on reduces that 135Hz dip a bit.
Oh ye of little faith....I doubt this dip will reduce much though!
Put a panel of 2" OC-703 on the sides of the soffits, that are on either side of the glass door, and cover that with fabric.There are some quite interesting differences between left and right speaker.., and with and without the soffit sides on
To be honest, I'd stand one of those up vertically in the middle of the rear wall, just on front or the treatment you already have there.I have four of these, which I plan to mount to the ceiling:
One on each side wall, and try the third one above the door on the front wall, angled across the wall/ceiling corner.I have three of these, which I plan to mount to the walls in the first reflection points either side of the listening position:
Hope springs eternal in the human breast!Hope to be able to do some work in the studio next week!
Better to do those NOW, before putting in the treatment! How will you know what to treat, if you don't first do the tests?I will do the string test later, and the walking test once I've put this round of treatment in.
Also, treatment will "dilute" the visibility of the real problems in the room that the "walking mic" test would otherwise reveal clearly. Since treatment lowers the Q, the problems will spread out more broadly and be less intense, thus harder to identify accuratel in the data...Yep.... but that's when you measure them in a perfect anechoic chamber, in a carefully calibrated test in a proper acoustic laboratory! When you put speakers in a real room, the room itself affects their performance. The room "loads" the speakers acoustically. Just like your car will perform nicely on a dead flat road that is perfectly smooth and dry, but will not even go in a straight line if the road is tilted to one side, angled upwards, with two wheels running on hard concrete and the other two in wet sand, with a strong wind blowing from one side, and rain... The car might be in perfect condition, with brand new, top-quality tyres, but it still wont go straight or accelerate the same way it would when tested under perfect conditions. The same happens to your speakers in a real room.I'd not spotted the 500Hz bump - the speakers are in theory +/-1.5dB between 39Hz and 20KHz, but anything's possible!
Because you are tightening up the room response! So now you are starting to see things that were hidden in the "mush" of the loose, incompletely treated room previously. It's normal, and it's a bit scary, which is why you need to start identifying individual issues now, and dealing with them individuality, instead of taking the "shotgun" approach of treating everything at once. Think of it like a patient arriving at a hospital after a car accident: he's covered in mud and blood and dirt and oil and shredded clothing, and you can't really see what's wrong with him. You know he's injured, but you don't know where or how bad. You do some tests, clean him up a bit, and now you can see the REAL wounds that were hidden under the grunge before. Since you can see them now, you can treat them now. They look uglier than before, because they were hidden in the fact that EVERYTHING looked ugly, so nothing was in focus as being worse than anything else, but now that he's cleaned up and you did the tests, you can see just how bad the really bad bits are. So you sew up the really bad wounds as you come across them, then keep cleaning and testing ans sewing up more and more, until he's fixed.Any ideas why some of the frequencies have got worse since adding the wall/ceiling super chunks?
I would go with something a little lighter and softer for there. What can you get in fiberglass insulation?I'll add some treatment to either side of the glass door (thanks for that tip) - we don't get OC703 in the UK - would RWA45 be as good?
That would be fine, but once again I'd go with something lighter than the mineral wool for that one.Between the door on the front wall - I was thinking of putting another super chunk there at that wall/ceiling intersection - the GIK panel won't fit.
Don't cut back on the low end response! You want to roll it off a little, not kill it entirely! Keep it at 37 Hz, but set it for Quarter Space. I PM'd you about that, and some other stuff we can do if you really want to get your room as good as it can be.Finally, I'm not sure how best to achieve -6dB reduction on the speakers - a picture of the rear panel switches is above. Maybe I'll go for Quarter space (A) and 47Hz? Currently set to Half Space (B) and 37Hz..
... or maybe with your interpretation of the data?Interestingly, the massive dipper at 136Hz is only so pronounced at my intended mix position. Something's obviously gone wrong either with the measurement, or the impact of the other changes on the room.
You need to stop looking at the frequency response so much! It's NOT the most important indicator of what's happening at this point in the process! It is one factor, yes, but focusing only on FR will only give you a small part of the big picture. If you look at the IR graphs, you'll see that -12" is no better than 0". In fact, the reflection is LARGER at -12 than it is at 0". It's 37.7% FS, at 12, vs. only 27.9% FS at 0"...It looks like the response would be quite a bit flatter 12" further back.
If you put your mix position at the point where the speaker axes intersect, then your ears will be off-axis for the speakers! Your EYES will be on-axis, but your ears will be off. So if you want to get your ears surgically transplanted onto your eyeballs, that would be fine... but you might find it hard to see the DAW with your ears in the way!I put the mic where my head would be, not where the speaker axes intersect,
Either your SketchUp model is grossly wrong, or you did something wrong with the string test. It should have clearly shown the floor bounce... I checked on your SketchUp model, and I can't make any triangle from the speaker to the mic at 0" that touches the wall. But I certainly can make one that touches the floor!- 3.6ms, which works out to a bounce length of 125cm = the side wall nearest the speaker
Once again, FR is only a small part of the equation. Take a look at the OTHER stuff that changed. At this point, you won't be getting more large changes in FR from adding absorption to the room. But you will in other areas, which clearly shows up elsewhere in REW. And the conclusion there is that the room is now too dead. There's too much bare face of absorption in the room. You will need to put strips of thick plastic across some of your bass traps, tuned to the right frequency ranges, to keep the room live. The decay times are even, yes, but too short.SPL comparison between yesterday and end of today, so the addition of ceiling and wall treatment, and changed speaker settings: