Time to tune my room

Here is the layout of my home studio, I am not a professional studio, this is only to have fun,... but serious fun! The walls are 2x staggered metal studs and 5/8 firecode drywall and layers of rockwool inside the partitions.. I am seeking for advise on tuning inside the room since iso seem to be fine like it is. There are 3 windows, the two smalls are 2ft and the big one is 4ft high (you can see them in the PdF). the two boxe to the left of listening are 4 ft high 19 inc racks full of gear. Many questions: dont know if I should go LEDE design or not. There seems to be a standing wave at around 300hz at the 2/3 back of the room. My first tests: I tune the sound of my sub and my KRK V6 at listening position ad it is fine , then I stand up and go at the 2/3 of the room and there seems to be 30% more bass there until the back end of the room. I guess I will need bass traps on the back walls.. Please tell me what you guys think. in order to have a good listening environment. Regards JF Montreal

Forgot to mention that the floor is a floating cement slab coated with an epoxy sealer. I was thinking of keeping the foor "live" and have the ceiling dead for 60% of it.(in front) Regards jf

here's the plan.

Thanks John for posting the plan. BTW, I was looking at my plan and it looks like it is not symetrical but in real life it is, I just did not know how to put the exact angles in the Autocad,... jf

do you have a diagram showing the room in context to the rest of the construction? have you done any measurements with something like the room eq wizard? in general though, you probably need some trapping and if this is the only problem spot, maybe a tuned slat resonator or panel trap is needed...

Thanks for the reply. For now, I do not have other data than critical listening in the room. Next week we will make some testing with a Smart Live and a good omni mic and I will have more data. Basically, I am wondering if the problem is that at the listening position the low frequencies get sucked or that they are inflated at the back of the room? Regarding the layout of the other rooms, unfortunately the only space that is available is what can be seen on the plan,... I believe you were asking this question to see if there were possibilities to buit bass traps...and maybe steal space from the other room to make deep basstraps. No unfortunately the treatment will have to be done within the room.. My question would be where would you start putting traps? Should i try to have either resonators / diffusers or basstraps in the back. I couls also have LEDE...??? Please help!!

ok, i was just wondering if this was built within a room where the corners could be used... the problem with bass trapping it you need some space for it to be truly effective. low bass requires more depth. maybe there are ways to utilize (above?) the ceiling to traps? another method will be to create targeted panel and resonator traps tuned to fix whichever frequencies are problematic since it may be possible that these will fit within your existing pace.

Thank you Glen, The ceiling is a great idea, That was kind of in my plan since I chose to have a wood floor and would deaden the ceiling. Let's say I can make 5 inches bass traps with Roxul maybe at 4-5 inches of ceiling. What about the walls? I was given 10 panels of 3x3ft 3 inches thick Auralex foam where would you suggest using them? Should I go for a LEDE variation? Should I install those 3x3 all over the front wall and on sides (with mirror trick) or should I leave some sections of front on dry wall? Should I install bass traps on all back walls? Could you please tell me where you would install them. Thanks ahead, I just want to avoid installing stuff that I will have to remove after.. JF

well now that we know the ceiling is an option, i'd wait until you have the measurements. i'd avoid putting in too many absorbers around the room to deaden it. i think LEDE was good for thinking about how the environment behaves but it seems that an overly dead room or one with a dead end, is unbalanced for many people. since you have a decently shaped room, i'd say wait until you have the measurements to decide on the treatments...

I did a lot more listening in my room. No matter what I do, I still have a problem around the console (no bass) and if I take one step back there is alot of bass,.. IU tried to make temp basstraps in the back of the room, then I tried to make temp bas traps on the front wall,.. I moved thet sub to the back of the room.. The console (8 ft wide) seem to block all the bass and it seems to accumulate in the back of the room. I filled the ceiling with 4inc thick roxul batts first in the front of the room and then in the back,.. Here is my question: is it possible that thte front portion of my room is "absorbing thte bass, and is there a remedy if I had to help the bass develop.. I understand that it is a small room.. Please help! Thanks JF

Aloha, Looks like a neat room. Got any pics? :D A few thoughts - - At a glance it appears that the mix position may be in or close to a null = no bass. Try positioning your seat about 64.98" (5'4") from the front wall and see if there's an improvement in bass response and then fine tune it from there. - How far from the floor are your ears when seated in the mix position, as there is another null that occurs on a vertical plane as well. Avoid the mid point of floor to ceiling measurement – either sit higher or lower if necessary Here are a few bits of information I’ve collected along the way that may be helpful. Use what is applicable and file the rest for future reference. :wink: • Soffits angled 30 deg. in from a flat wall result in speaker baffles being perpendicular to the two legs of equilateral triangle comprised of two speaker centers and a point about 10" behind your head • The baffle extension (the face of the soffit) should be as large as you can make it, up to about 45" in each direction from the woofer in a system with a LF cutoff of around 45 Hz - There's a formula based on LF cutoff that ensures full 2 pi response for the woofer if the baffle is at least the size obtained in the formula's solution - • Monitors should NOT sit on the console but behind, placed on heavy decoupled stands - console placement causes early reflection problems in most cases, unless the console is slanted down in front a LOT. • Distance to wall behind speakers will change response drastically - there is a wall bounce calculator on the Acoustics forum that's fun to play with (needs Excel) • Moving either speakers or your head by as little as an inch or two can sometimes make drastic changes in response, due to modal peaks and dips. • Left/right room symmetry (at least within a foot or two of ear height) is important for good stereo imaging. • Roughly 38% of total room length from the front wall • Monitor angles 60 degrees • Monitor height – avoid mid point of floor to ceiling measurement • Angled side absorption panels – left/right of mix position • Side walls 6-12 degrees Hope this helps, Aloha 8)

I made more critical listening in my room... It seems that there is an obvious problem at the listening position (bass null). I believe I know why,... the ceiling is a bit lower in the front with a slight angle. So what is causing my null could be because monitor is basically at 50% of the distance between the ceiling and the ground. Q: Is there a remedy or will I have to flip the configuration of the room? Next Friday a friend with a Smart Live and other machines to come to my place to take measurements with an Earthworks omni. What measurements should we make? I was thinking of RT60, pictures of different tones in the room, pink noise , white noise any suggestions??? Thanks JF

Aloha,

the ceiling is a bit lower in the front with a slight angle.

Just to verify...the angle runs up from the front wall to the rear of the room, yes?

So what is causing my null could be because monitor is basically at 50% of the distance between the ceiling and the ground.

That could be one of several issues based on your drawing. - Where is your current mix position measured from the front wall? - Try re-positioning your mix position seat to about 64.98" (5'4") from the front wall and see if there's an improvement in bass response and then fine tune it from there. - How far from the floor are your ears when seated in the mix position, as there is another null that occurs on a vertical plane as well. Avoid the mid point of floor to ceiling measurement – either sit higher or lower if necessary

Q: Is there a remedy or will I have to flip the configuration of the room?

Try starting with the above suggestions and then let us know the results. Hope this helps, Aloha 8)

Aloha to you, Quote: Just to verify...the angle runs up from the front wall to the rear of the room, yes? Answer: Yes it does, it is a moderate angle (15 deg or so) on a 3-4 feet distance, it basically ends 1 foot after my monitors and then I have a 45 deg that finished at the ceiling. This was all made to enclose the main beam...(I will post pic later this week). Q- Where is your current mix position measured from the front wall? Q- Try re-positioning your mix position seat to about 64.98" (5'4") from the front wall and see if there's an improvement in bass response and then fine tune it from there. A- My current mix position is 5.5 ft from front wall as suggested. Q- How far from the floor are your ears when seated in the mix position, as there is another null that occurs on a vertical plane as well. Avoid the mid point of floor to ceiling measurement – either sit higher or lower if necessary A- My ears are at about 50 inch from ground. I did try to lower the chair, but there was not a great improvement. I also tried to raise the sub and lowered it , I also tried it in the back of the room but it did not make sens. For now the front portion does not have any acoustic treatment so it is all painted drywall (layers of 5/8). Should I try to put something to deaden the ceiling or should I put a carpet in front of the console. (I guess it would not affect the low frequencies,..). I did follow your advise to put basstraps on the ceinlin (4" Roxul) everywhere. Still alot of bass everywhere but at the listening position. And if I roll back the chair of 2-3 ft bass is natural and full... Are ther any measurements I should make tomorrow that would be helpfull ?? I will post pics this week-end. Thanks a lot for your time. Regards jf

Dear forum, I made a lot of testing last night, let me share the methodology and the results: We used Smart Live RTA through a PreSonus Firebox and listened with a Earthworks omni and we also had a Phonic RTA to estimate the RT60. We evaluated a lot of different options as to monitors placement as well as the sub placement. There seems to be two problems in the response of the room: there is a boost of 12-14db at 45hz as well as a dip of -14db at 105hz. The rest of the frequency range seems to be pretty flat. RTA seems to be .36 so there is not a lot of natural reverb since the room is small. My biggest problem is still the fact that I could tune the listening position pretty well (where there is a null) but then there would be way too much bass as soon as I would take even a 3 ft step back where the sound was not natural (too much bass). I imagine that we have two options: fix the null (how?) or try to fix the rest of the room... I post some pics later this week-end. Your comments would really be appreciated! Merci JF

the 45hz probably needs a panel trap to get that low. the 105hz should be treatable with a slat resonator, or you could use a panel trap. presumably there is a peak at 105hz and you'll want to find it and put the trap there - most likely your ceiling. the advantage of the panel trap is its thinner than an equivilent resonator at low frequencies. Check Ethan Winer's site for details on constructing panel traps.

Dear forum, After all the measurement, testing , moving the gear around,.. questions , answers, I still dont know what is the real fix for my situation... If I tune the listening position (small sweet spot at the console), then I still have a boost of 20db of low end (40hz) at the end of the room.... So if I listen with an artist who's sitting in the back, he will say WOW there is way too much low end!!! It is established that there is a null at listening position,... IBut is it possible to fix that specific problem?? I still want to be able to listen at finished product on the couch or just standing in the room....Is it possible? Thanks for the help, it is really appreciated. jf/Montreal

I made the decision to reverse my studio configuration because the ceiling was lower at one end,... So it changed my plans a lot but I still have the same problem: Nice and focused and alomstt flat at listening position but 45hz spike two feet from sweet spot which makes it almost useless for anybody but the person on the console!!! I would please ask for like your opinions: I will built bass traps ,made of two layers of 3inc of Roxul. Panels will be 4x5ft. I will make 3 of them to put on each of the the back walls... Should I put lats of wood over to reflect some mid-H frequencies??? All you input is very valuable to me, please help me savfe my marriage,... (joke, but almost true,..). Thanks! jf