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Post by protools1 on Jan 19, 2022 17:16:41 GMT
Hi everyone, its been a while since I posted here. Trying to help a friend who got a big "finished" room for year to work out of. Dimensions L 15 W 29 H 12... (dimensions doesn't fit Bonelo's) The front have a glass that looks into live room that almost as wide the as the room about 20feet wide Big speakers are ATC soffit mounted in the wall on top of the glass. In front of it is a large console and in the back a huge QRD diffuser that covers about 3/4 of the back wall from bottom which seems overkill since the engineer's chair is not that far away maybe 6-7 feet.
Room looks great but doesn't sound that good to me. I was told it was build by some famous designer (smh) Low end is weak, most of low mids are smeared, very little details from high frequencies which knowing ATC something is wrong.
They have white eqs. for big speakers which I tried to mess, boosting 40 or 50 Hz do very little even at +10bds, probably a room mode i am fighting with, boosting highs +5 dbs 8k and 10k helped a bit but not that much
There is a big dip in the mid range sounds scooped. I noticed they have a huge cloud that is made of 3/4 inch Plywood with lights and on top are few layers of pink stuff angling to the back a little. I told them to put a couch in the back in front of the diffuser and that helped a bit. I was also thinking changing the cloud to some more absorptive to start. Maybe bring some insulation bags and measure what that sounds like.
Not try and redo the room since visually it looks very impressive what are some of the steps i can do?
Thanks PT
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Post by rock on Jan 21, 2022 13:58:46 GMT
Yeah, taking REW measurements will give you a better idea of what you're dealing with. Take before and during to confirm any changes you make are working for you.
You describe the cloud made of 3/4" plywood with pink on top. To me, that sounds like the entire bottom is reflective plywood??? If I understand correctly, reflection is exactly what you DON'T want a cloud to do. So yeah, replacing (or redesigning) it with an absorbent cloud should help.
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Post by protools1 on Jan 22, 2022 7:23:09 GMT
Yeah, taking REW measurements will give you a better idea of what you're dealing with. Take before and during to confirm any changes you make are working for you. You describe the cloud made of 3/4" plywood with pink on top. To me, that sounds like the entire bottom is reflective plywood??? If I understand correctly, reflection is exactly what you DON'T want a cloud to do. So yeah, replacing (or redesigning) it with an absorbent cloud should help. thank you, yeah its type of expansion ceiling starts lower upfront and goes higher in back. I went up and saw thats its about 3/4inch plywood with a small amount of pink fluffy stuff laying on top of it about 1 foot off the actual ceiling. I took measurements and they are not great at all. Pretty steep deep around 62, and 250, than big roll off below 40Hz, high end dips down around 2k and goes even steeper above 8k. Cloud will only help so much, i guess it will be the most economical way instead of ripping the walls down and redoing everything.
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Post by rock on Jan 22, 2022 15:13:28 GMT
So as is often the case in the low end, you have room mode SPL and most likely modal ringing issues too. If you're using REW, the "waterfall" display will show you modal ringing expressed in time (ms). For the low end, limit the test range to 300 Hz with no smoothing. You see your Schroeder f is pretty low at 127Hz. amcoustics.com/tools/amroc?l=29&w=15&h=12&ft=true&r60=0.6 due the the size of your room. Your 2K and 8K issues are generally reflection issues. OK to use smoothing for Mid/Hi tests. Did you try measurements at different listening positions? You may/should notice some differences. More absorption can help both Low and Hi but you'll generally need a significant amount to make a difference at least in the low end. The hi end might be easier with targeted RFZ panels and LP/ speaker adjustment etc. These are general ideas, maybe more experienced members can help with finer details. If you have not seen this yet, Hexspa has a series www.youtube.com/watch?v=AQ3fbAjL6SI "How To Set Up A Room". It may help you get the best out of what you've got.
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Post by rock on Jan 22, 2022 15:43:52 GMT
About your cloud: You know it's primary purpose is for early reflections off the ceiling but also can help the floor to ceiling room modes with increased thickness.
Because of the large width of your room, you may need two; one for each side/speaker. For the reflections, each needs to be centered around the point on the ceiling were a "line of sight" from the LP to each speaker is located on the ceiling. Increase the area/size of the cloud as the distance increases due to the nature of how sound waves "grow" in width as distance increases...like waves in a pond only in 3D it's more like a cone.
If you find you have large enough clouds on each side but end up with a "bare area" overhead, you might decide to put up a third cloud in the middle to make an almost continuous cloud... or just make one big one! This will also help with LF control of room modes.
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Post by protools1 on Jan 23, 2022 2:42:45 GMT
So as is often the case in the low end, you have room mode SPL and most likely modal ringing issues too. If you're using REW, the "waterfall" display will show you modal ringing expressed in time (ms). For the low end, limit the test range to 300 Hz with no smoothing. You see your Schroeder f is pretty low at 127Hz. amcoustics.com/tools/amroc?l=29&w=15&h=12&ft=true&r60=0.6 due the the size of your room. Your 2K and 8K issues are generally reflection issues. OK to use smoothing for Mid/Hi tests. Did you try measurements at different listening positions? You may/should notice some differences. More absorption can help both Low and Hi but you'll generally need a significant amount to make a difference at least in the low end. The hi end might be easier with targeted RFZ panels and LP/ speaker adjustment etc. These are general ideas, maybe more experienced members can help with finer details. If you have not seen this yet, Hexspa has a series www.youtube.com/watch?v=AQ3fbAjL6SI "How To Set Up A Room". It may help you get the best out of what you've got. Thanks again for your knowledge, i did measure and I looked at Hexpa series previously, here are some measurements
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Post by protools1 on Jan 23, 2022 2:43:48 GMT
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Post by protools1 on Jan 23, 2022 17:40:24 GMT
if i understand you correctly and the speakers are in the wall mounted in order for the cloud to be of use it has to be pretty thick and be as big as an area to cover sound dispersion ...thinking about the original design that whomever made the compression or whatever it is ceiling that also facing the back huge QRD diffuser almost the size of the back wall...what was the point?? was it to make the room length wise larger sounding but disregard how accurate the sound is?
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Post by rock on Jan 23, 2022 19:08:06 GMT
Thanks for posting your graphs. They actually look pretty good considering they are pretty much within a 10dB range. That'a what we here usually consider as good as you can practically get.
I overlooked the fact your speakers are flush mounted and if your ceiling reflects to an area behind the listening position, the idea is that you will not hear the early reflections off the ceiling. With the extreme width, the same idea that there will be minimal influence from reflections, if any, from the side walls. That being said, it's my inclination to try an absorbent cloud and also, check the reflection angles/paths from speaker-wall-LP for both speakers with both walls (4 paths). Depending, it might not be a bad idea for RFZ absorbers on side walls too if you don't have them already.
In going over your graphs, I see they line up pretty closely with the room mode calculations. This means if you want to smooth out your SPL further, you just need more broadband absorption all over.
What your QRD is doing may be showing up as fairly regular dips and peaks in the mids and highs. Who knows, maybe it's one of those times where "If Some is Good, More is Better" does not apply? Sorry, IDK
And then there's Sonarworks room correction. I have never used/tried it but it might be a solution.
Finally, I probably should have mentioned this first: How do mixes translate? It may be counterintuitive but it might be worth a try. I hope you find something that works, let us know how it goes!
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Post by protools1 on Jan 23, 2022 20:44:43 GMT
The mixes don't translate that great so my friend brought his own nearfields Focals and set it on top of the console. They sound better still not enough low end. when i listen there is a-lot of thumping, 100-200Hz build up. Same is my observation with ATCs in the wall, also from the graph and listening it all the high end is gone. Focals had high freq adjustment and i had to turn it all the way up. My reference was Steely Dan "hey 19" For near fields, sub maybe required and maybe decouple them from the console on some pads or something similar. thanks for you help Rock.
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Post by Hexspa on Jan 26, 2022 10:12:58 GMT
Ethan has shown that speaker decoupling has minimal effect. Check your decay. The number I use is 20dB within 150ms from around 63-250Hz. Above that is usually quick and below that is harder to do. You want as even a taper as possible with longer decay toward the bottom. You can use the REW decay plot with your initial response and 140-160ms only showing.
If you have more bass at 150Hz, it makes sense because you have longer decay above and below that range. You'll naturally add more wherever there's less in your room and vice versa. Further, mixing low end is perhaps the hardest part so there's that; generally I find that I need a lot less than I thought.
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Post by protools1 on Feb 1, 2022 3:51:57 GMT
Ethan has shown that speaker decoupling has minimal effect. Check your decay. The number I use is 20dB within 150ms from around 63-250Hz. Above that is usually quick and below that is harder to do. You want as even a taper as possible with longer decay toward the bottom. You can use the REW decay plot with your initial response and 140-160ms only showing. If you have more bass at 150Hz, it makes sense because you have longer decay above and below that range. You'll naturally add more wherever there's less in your room and vice versa. Further, mixing low end is perhaps the hardest part so there's that; generally I find that I need a lot less than I thought. Hi Hexspa. Thank you for chiming in. I hear you on decoupling. I think one can get used to a room after a while and know what to do, but would love to learn more. For now its through these graphs. Here is a decay as I understood you are referring to. Attachments:
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Post by Hexspa on Feb 4, 2022 18:33:23 GMT
I misread what you said the first time. You're saying you hear thumping in the room, not your mixes, right? Look at your response: big peaks just above and throughout 100-200Hz and virtually no decay. 3dB of decay at 150ms (if that's what your decay plots are showing) is not ideal. You want something more like 20dB.
Different people have different goals but I'm with the people that say you should have a tapered decay. The way you accomplish that is through absorption. Make sure to create an RFZ then take care of your corners and parallel surfaces. All the info you need is probably already on this site.
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Post by protools1 on Feb 4, 2022 19:10:12 GMT
Thanks I am with you on RFZ...so you are saying the low end should have more decay at 150ms? the room is very wide pretty much have of the length...I have some ideas and I suggested for the studio owners to deal with it. For now they went to the original designer to confirm why we are getting such a crappy results if they spend bunch of money already. Like I mentioned ATC are hard mounted int he walls (too high in my opinion, i guess they had to get above the glass) point to the back instead of closer to the mix position.
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Post by Hexspa on Feb 5, 2022 10:50:23 GMT
More decay meaning the sound fades faster. Think about it: you want to hear the sound once! If it just hangs around, you're still hearing it after the original signal is long gone. Like I was saying, after 150ms the decay in that room is just 3dB. Try playing two sounds at the same time 150ms apart and listen to what happens compared to bringing the fader down to -20dB within that time (and keep the fader moving down). The second one lets you hear the static track better and your room is no different.
Or, if you prefer a synth analogy, people generally make bass patches monophonic so that each note comes in clean and without interference from the previous one. However, since we can't choke group our acoustics, we have to settle for a fast decay time with zero sustain.
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