Small Studio Acoustic

Started by Whitecones on 22 December 2010. 8 replies.

Originally posted at johnlsayers.com, topic 15410.

Whitecones22 December 2010#1

Hello That's the first time I post in this forum, thank you to exist, I hope to get some helpful suggestion in here :) So, this is my studio, here I'll do mixing and production Dimensions (Empty room without any treatment) Length: 5.10 meters (16.74 feet) Width: 3.20 meters (10.5 feet) Height: 2.70 meters (8.86 feet) Construction The left wall, the ceiling and the floor are made of reinforced concrete (I hope this is the right term, I mean concrete with steal sticks inside of it, as usually, here in Italy, houses are made of). Over the floor there is hard wood with transparent paint over it, I mean lucid as usual wood floor are. The right and the front wall are made of perforated bricks. The front wall is covered with rockwool 4" thick (so the length with rockwool becomes 5 meters) Treatment The rockwool I used is "Rockwool Acoustic 225" 70 KG/m3 (mostly, unless specified otherwise) Front wall is covered with 4" rockwool Front corners (L-R) are filled with rockwool Front upper corner is covered with two corner traps Ceiling is covered with 10 traps 4" thick (2'x4' inch) spaced around 4" or 5" from the ceiling (should be 4", but there's some tolerance) In the library on the left, "under the bridge" is filled with rockwool 8" thick The empty space under the left speaker stand (where are the ns10) there's a heavy trap (rockwool 135 kg/m3) 8" thick In front of it there is a "corner trap" I had at hand, mixed 70 kg/m3 and 135 kg/m3 on the back (the red one on the floor) Over the library on the left you can see another red object, which is another trap made of rockwool long 5' long (1.5 meter) x 8" x 14" Behind the speaker stand (the one on the short wall) there is a trap 2'x4' 4" thick made of rockwool, this was 50 or 40 kg/m3 I don't remember, placed horizontally over the front wall a bit angled with the floor. On the left corner superchunk there is a small 2'x2' 4" thick rockwool (the white one you can see in the picture) On the right corner superchunk there is a small 2'x4' 4" thick rockwool (even this is white) Over the door there is a 2'x4' 4" thick trap, spaced 4"/5" from the door On my right, over the right library, there is a 2'x4' 2" thick trap (white) Oh, on the right, between the ns10 there is another 2'x2' 4" thick trap (white) On the right library, on the back, there is another 2'x2' 4" heavy thick trap (white) made of rockwool 135kg/m3 Beside that trap there is another one identical Behind that trap there is another trap, placed over the right back corner filled with rockwool (135kg/m3) The left and right back corners are filled with rockwool (135kg/m3) Over the right library there is another trap long 5' (1.5 meter) red, as the other one in the other library, but all made of rockwool 70kg/m3 Beside the window there is a corner trap (white) made of rockwool On the left back corner there are two traps 2'x4' 4" thick each (the part with the amps) Behind the amps and the guitars there are 4 traps 2'x4' 4" thick, paired, I mean two behind the amps and two behind the guitars, spaced from the wall because down, near the floor, there is a small radiator that doesn't let me place the traps against the wall.. so near the floor they are spaced around 4"/5" a bit angled I hope I haven't missed anything Room Photos http://img525.imageshack.us/img525/9844/img0120nc.th.jpg Uploaded with ImageShack.us http://img155.imageshack.us/img155/1676/img0121mf.th.jpg Uploaded with ImageShack.us http://img843.imageshack.us/img843/9716/img0122ta.th.jpg Uploaded with ImageShack.us http://img510.imageshack.us/img510/7820/img0123o.th.jpg Uploaded with ImageShack.us http://img442.imageshack.us/img442/2991/img0124j.th.jpg Uploaded with ImageShack.us http://img718.imageshack.us/img718/3695/img0125qe.th.jpg Uploaded with ImageShack.us http://img232.imageshack.us/img232/9894/img0126nu.th.jpg Uploaded with ImageShack.us http://img831.imageshack.us/img831/8065/img0127yf.th.jpg Uploaded with ImageShack.us http://img408.imageshack.us/img408/7499/img0128aw.th.jpg Uploaded with ImageShack.us http://img413.imageshack.us/img413/3856/img0129f.th.jpg Uploaded with ImageShack.us http://img526.imageshack.us/img526/6936/img0132zb.th.jpg Uploaded with ImageShack.us http://img842.imageshack.us/img842/4296/img0133br.th.jpg Uploaded with ImageShack.us http://img87.imageshack.us/img87/9752/img0130d.th.jpg Uploaded with ImageShack.us http://img3.imageshack.us/img3/3650/img0131te.th.jpg Uploaded with ImageShack.us Mesurements Mic at 196 cm (38% of the room) Mic height 106 cm (my ears level) Tweeter level 103 cm (it was 106 but I've removed the auralex mopad because it was a little better) Stand at 30 cm from the back wall Desk at 37 cm from the stand Speakers toed in 7cm (the equilateral triangle axes cross 25 cm behind the mic capsule, there are reasons why I've done this, I'll move them later if necessary) http://img209.imageshack.us/img209/4503/211210196cm30s37dtri.th.jpg Uploaded with ImageShack.us http://img43.imageshack.us/img43/497/211210196cm30s37dtriw.th.jpg Uploaded with ImageShack.us http://img833.imageshack.us/img833/8329/211210196cm30s37dtrietc.th.jpg Uploaded with ImageShack.us Only Left Speaker http://img808.imageshack.us/img808/2170/211210196cm30s37dtril.th.jpg Uploaded with ImageShack.us http://img833.imageshack.us/img833/6936/211210196cm30s37dtrilw.th.jpg Uploaded with ImageShack.us http://img220.imageshack.us/img220/7172/211210196cm30s37dtrilet.th.jpg Uploaded with ImageShack.us Only Right Speaker http://img697.imageshack.us/img697/5241/211210196cm30s37dtrir.th.jpg Uploaded with ImageShack.us http://img27.imageshack.us/img27/5426/211210196cm30s37dtrirw.th.jpg Uploaded with ImageShack.us http://img337.imageshack.us/img337/9831/211210196cm30s37dtriret.th.jpg Uploaded with ImageShack.us My first goal has been to tame the dip with absorbers and finding the best position in the room (I'm still working on it) then, if the absorber placement is definitive, I can start building frame around them, putting slats over the faces, so the room will sound more live. Then the last step will be diffusers. Here the wood is very expensive, so I needed to have an idea about where to put the rockwool absorbers before building frames etc. What do you think? Is it a workable solution? How can I improve it? Let me know if you need more informations Thank you :D

Whitecones22 December 2010#2

History Well, I started treating this room 2 years ago, or so. The problem is I can't get a rid of the library, I'm in my family home.. unfortunately, but is the only room I have at my disposal. So I tried many solutions, workaround, to get the best result I can because also I'm particularly picky with acoustic. I mean when I mix I think I'm always eqing the room and that is very frustrating. I've done really really a lot of attempts to get a better response. I've spent the last three weeks, firstly taking everything out of the room (except the libraries, well the right library yes, because was easier, but was better with the library then without) moved the libraries to have them more symmetrically, then I tried to find the best placement for the speakers, even changing the listening position to the window side, but I had much more problems in the lows, and the lows where way more shelved under 200 hz or so. I also tried to play with traps with the speakers on the window side, but without good results. Then I went back to the wall where you see the speaker are in the photos and I tried different placement, different solutions. With the empty room (except for libraries) I placed the monitors against the wall, the response was http://img401.imageshack.us/img401/7797/011210start.th.jpg Uploaded with ImageShack.us http://img145.imageshack.us/img145/4139/011210startw.th.jpg Uploaded with ImageShack.us http://img403.imageshack.us/img403/9616/011210startetc.th.jpg Uploaded with ImageShack.us I thought was "a good start" because all modes where aligned But in the end, playing with traps and everything I reached that result and couldn't get anything better than this http://img824.imageshack.us/img824/1407/011210end.th.jpg Uploaded with ImageShack.us http://img839.imageshack.us/img839/5790/011210endw.th.jpg Uploaded with ImageShack.us http://img151.imageshack.us/img151/3914/011210endetc.th.jpg Uploaded with ImageShack.us There was no way to make the ceiling traps work, I mean they made a dip deeper and deeper in the low mids, these graphs are without traps on the ceiling So I emptied the room again, I placed the Left library where it was before, and I played with traps getting a little better result, still not near as it was before. Then I moved the speakers where they were (I found that placement by ears and using the test cd from real traps) 30 cm from the front wall and placed everything where it was and I got a much similar result as it was before Then I moved the right library where it was and placed everything inside the libraries as it was before and I got an almost identical response. Then I played with traps and I got a little better result, the one of the graphs I posted in the previews post. Still the Left speaker is much different to the right one, the right one is quite good, but the left probably compromise a lot the end result. The last time I placed everything in the room, the desk was in the room, so all the traps placement I moved compared to the original position (as it was before these 3 weeks) has been influenced by the presence of the desk, while in the other attempts the desk was outside and when I took it in, it was a big mess compared to without the desk. Now if I take out the desk, is a big mess, it's better with the desk in. Approach My approach when moving stuff, when I try to find the best placement for traps has been, starting from the bottom, I played the 76 hz tone (consider the 76 hz dip changed depending on the placement, it went from 73 to 78, I don't know maybe this info is useful for you) and walked around the room to find places where it was louder, using also an SPL meter But unfortunately only few places where it resonates loud were good to place a trap, in fact in many places the dip become deeper. The good places where mostly on the back wall, and on the right, where the amps are. The ceiling corner trap absorb a lot the 76hz dip, also the two over the left corner trap. And so on, I mean in general I used that method, where I found a dip, I played a sine on that freq and I walked in the room to find the best placement for traps, but considering many of them made things worse, I also tried just placing some traps around, and I discovered, for example, the heavy black trap under the bridge of the yamaha speaker stand, does a lot aligning the lows (the part you see more flat) and the traps under the library bridge does a lot too for the 76 dip and in general for the lows Listening Experience The room sounds controlled in the low end (I'm talking about decay), but working in there is quite fatiguing, probably I have to many highs and the lows are like "shelved". I tend to cut often too much low mids, mids, hi mids, and I think this is sometimes right (in frequency), sometimes influenced by the room, generally the amount of the cut is too much. When I go in the car I have planty of low end (my car hasn't a sub, but has big woofers, good mids and tweeters, I have a quite natural sound, not so defined in the low because it is always a car, but much better then all the cars I've been in). Speakers Part of the highs are because of speaker design, the PMC TB2+ have a lift on the highs, because the tweeter design has a wider dispersion and PMC suggest to use them not in perfect equilateral placement, but with the axes that cross 50 cm behind your head, to have a wider sweet spot because, they say, usually when you use outboard or in general when you mix, you move around and your head isn't always in the same position. So my room already has a lot of highs plus and specially the lows are a bit shelved, so I think I'll get a second amp to bi-amp them and take down the level of the tweeter or I'll take an eq. Why PMC? I've used Dynaudio BM5a, good overall, very hifi, poor transient response, not articulated lows, a bit boomy of their own, I mean the classic hi fi effect in the lows. I changed to KRK VXT6, great speakers, great transient response, I tried to fill the port with some foam because I like sealed speaker. Then I took just to try because I found them used (I was interested about the transmission line concept), those pair of PMC TB2+ and an Adcom 545, and wow wonderful image, they are very 3D, very articulated, ultra clean lows, very detailed mids, unbelievable transient response (a conjunction of the KRK transient response and NS10, Auratone), unfortunately too many highs. That's why I'd like to keep these speakers. Next step, I found a used TLE1 sub and I want to try with it, maybe even the highs will feel more pleasant having the lows more at highs level. And then I'll eq them or reduce them with an amp, if are still too much.

gullfo23 December 2010#3

empty the room completely - everything not nailed down. then set up your speakers and the omni mic in the listening position and measure. also so a single speaker in the low front corner and the mic in the opposite upper back corner. this will give you the baseline of you room both from a mode perspective and the monitors/listening position. start with the monitors @ 70% of the room width and 100mm off the front wall and turn them on 30° to the listening position. set the mic dead center of the room and 38% of the room length from the front wall. you might find you need to move the speakers and listening position to get it close. make a triangle with the two speakers and the mic. once you have that, it is then possible to begin to determine what you need. at the very least it's likely to be bass trapping across all corners of the room, side and top absorbers for first reflection points, and back of the room. basically start with 8 absorbers. re-measure. then you can determine if you need to add more or reposition etc. finally, bring in the library and desk and make them fit within the treatments. re-measure. if need be, consider moving the library out into another room or storage. offer to pay for the storage if need be. if you're serious about the sound, don't let the furniture dictate your treatment decisions. otherwise accept what you cannot change and alter your workflow to accommodate more A-B testing of mixes to accomplish what you want.

Whitecones23 December 2010#4

thank you gullfo, I'm serious about sound, and your procedure is exactly what I would do, but it's quite impossible for me, you don't imagine my situation. Anyway, how it is the situation now? That bad?

Whitecones23 December 2010#5

Whitecones23 December 2010#6

I mean, aren't these measurements around +/- 5db? And the ISD is under -25 db I haven't seen many better then this, or there's something hidden I don't see and you see that doesn't work that make them wrong?

gullfo23 December 2010#7

Maybe I misinterpreted something, I was understanding that you weren't happy with the room and needed to troubleshoot it... Yes, the frequency response and ISD look fine to me so if you're happy I'm happy :D cheers!

Whitecones24 December 2010#8

well, I'm unhappy because I haven't enough low (for mixing yes, for production not) and the highs are hyped (also because of the speaker) but I was thinking to try before with a subwoofer (probably placed on the left considering the bass response is poorer on the left speaker) and then trying bi amping the speakers and lowering the tweeter volume, or if it doesn't work, with an eq. Then if I get a good result, I stay in that way, if it's not enough, I'll think to find other solutions Now I prefer spending some money for that, then empty all the room etc, not because I wouldn't like the idea, but because I don't even have the place to store the stuff in the room temporary So, I was looking for some opinion to the measurements and maybe some ideas to improve it a little bit, if they comes to mind Just because I haven't much experience treating rooms, except mine (to which I'm almost a guru :P) and maybe I've not the experience to interpret properly the room Another thing I'm dubious about is the L-R symmetry, is so screwed or is it workable? Honestly to my ears is fine, I don't notice it, I hear the sounds well centered, but I don't know, from the graphs appear quite different By ears what I notice is that unbalance between lows and highs and that, mixing here, I think I cut too much some mids and some highs (probably to better hear the lows, so maybe with sub and bi-amp, that problem will be solved or improved) The two majors downsides of that unbalance between lows and highs is that I generally hear the sounds more "digital sounding" and it's more fatiguing. Again I think-hope with a sub and biamping them, I'll get a rid of that problem So, what do you think about these considerations? Thank you so much!

gullfo28 December 2010#9

how well do your mixes translate to other systems? car? club? radio? home stereo? etc etc? if you're getting good translations across your material then you're good. if you find that your mixes don't come across as you expect, then you have a problem. maybe there is another way to layout the library so it's out of that spot but still in the room? if not, then you may need the sub and you may need to cut some HF to get the balance you need in order to achieve a good mix.