New space - studio in Athens

Should I consider measurements' ringing or the dimensions' modes for building my traps? According to room's dimensions the lower axial modes are: 1 19.71 Hz D0# 1-0-0 ax 2 38.98 Hz D1# 0-1-0 ax 3 39.43 Hz D1# 2-0-0 ax 4 43.42 Hz F1 0-0-1 ax I can see on the measurement of untreated room the lower mode at 19.7Hz: But after superchunks, hangers, diffuser and clouds, the low ringing is at 18.2Hz: So I am thinking that makes more sense to treat according to modes and not what I get on latest measurements.. I would appreciate any input on this :D

almaelectronix wrote:

Should I consider measurements' ringing or the dimensions' modes for building my traps? According to room's dimensions the lower axial modes are: 1 19.71 Hz D0# 1-0-0 ax 2 38.98 Hz D1# 0-1-0 ax 3 39.43 Hz D1# 2-0-0 ax 4 43.42 Hz F1 0-0-1 ax I can see on the measurement of untreated room the lower mode at 19.7Hz:

Not preserved: untreated.jpg

But after superchunks, hangers, diffuser and clouds, the low ringing is at 18.2Hz:

Not preserved: treated.jpg

Not preserved: vs.jpg

So I am thinking that makes more sense to treat according to modes and not what I get on latest measurements.. I would appreciate any input on this :D

Porous absorbers can have an effect on membranes, so I would treat the ringing according to your measurements rather than your predicted room modes. I have to say though, I am not optimistic about your proposal of creating lots of small traps and only treating a relatively small area on your front wall... I know much of your treatment is already in place now and changing anything will change your measurements again, but I think I would build large traps and cover as much area as possible on the rear wall, behind porous treatment if possible. Paul

Hi Paul and thank you for your input , I really appreciate!

Paulus87 wrote:

Porous absorbers can have an effect on membranes, so I would treat the ringing according to your measurements rather than your predicted room modes.

I further studied the LMA's and read today what the designer says: "These traps are intended to tame room modes, so measure your room dimensions and calculate the modes. Measuring with microphones does not necessarily identify problematic modes." So I think I will go for room's mode.

I have to say though, I am not optimistic about your proposal of creating lots of small traps and only treating a relatively small area on your front wall...

About that he is writing on design notes: "The box L x W is not critical but should be kept small compared to the wave length of the resonant frequency. The limp mass bass absorber is not effective beyond 300Hz for this reason. Typical L x W would be 60 x 40 cm for frequencies below 100Hz, and 40 x 30 cm for frequencies above 100Hz." I still don't know how many of them will be needed so I will build, measure and keep going according to results. Mine will be 50x60cm and I 've got space for 12 boxes on front wall. There is this guy who made just two boxes of 40x60cm, placed on front wall, to tame his first axial mode on 61Hz and had great results regarding decay and frequency. Check his graphs:

I know much of your treatment is already in place now and changing anything will change your measurements again, but I think I would build large traps and cover as much area as possible on the rear wall, behind porous treatment if possible.

Yes the pressure zones for this mode is the front and back wall so both of them will give the best results. The whole back wall is full of hangers 80-100cm deep already so it already contributes on taming this mode. It was challenging to complete this back wall project so I prefer not to mess with it for now. I will just start with the front which is untreated and see how it goes..

Hi all! Merry Christmas and Happy new Year! My best wishes for all people! Some progress from my room. Finished the front wall LMA's and insulation. Here are the pics and measurements.

I had to make better use of the only space available on the back wall in order to tame the low axial room mode. So I said goodbye to my hard built diffuser and 2 LMA's took it's place. No filling this time for higher Q. Photos of the progress: There was a major improvement on 19Hz ringing. Check the spectrogram. Also attaching the mdat

definitely an improvement! nice work overall! yeah, tuned treatment typically aren't very large compared to the wavelengths involved since their concept is to resonate at the target frequency but then are severely damped to effectively burn off that energy. so a number of smaller tuned treatments placed around the room are often very effective. however, it's takes a lot of work (and often re-work) to successfully build and place them. tuned treatments are pretty much a last resort when the broadband treatments are in need of some help on select few problem frequencies/room locations.

Thank you for your kind words!! I agree with everything you said. True for me was the last resort. And hopefully the rest of the treatment will have some impact too..

So change of plans.. Ceiling clouds and corner traps (bin bags) removed. Will make the whole ceiling absorptive and hide the HVAC exhaust air path inside the false ceiling. Will also add some tuned limp mass bass absorbers on key points. Ceiling's membrane traps: New path for the exhaust air: Ceiling's frame and insulation:

And front part of the ceiling, rebuilding this front wall to ceiling corner trap. Hiding power cables: Floor leveling:

Fixing walls!!! Removed the old paint, 2 layers of plastering, 3 times sanding, 2 coats of primer, 3 coats of paint.

Side wall first reflections tretament: 3 layers of light fabric (dense woven) for particles protection:

that is looking really good!

Thank you! Treating the side walls flutter at the moment will post the measurements soon!

Very impressive... how high is that ceiling? Looks like 10m but I guess it is not that high.. Great work.. 8) scott

Hi Scott, thank you very much! Hehe yeah it sure does though it's 4 meters (13feet). It's cool for its properties and the fewer problems that introduces. But it's been a struggle for me building things and working up there. If you re doing it yourself as I do, there's a lot up and downs on the ladder and scaffolding.. But I am almost there :)

Side walls polys for flutter echo and hiding the ugly beams: Flutter panels and more polys:

last of the side wall polys and boards: particles protection and final cosmetic fabric: bringing HF energy back with slats, polys, polyethelene strips. And final fabric:

Ceiling's fabric, wooden details, hvac registers, lights: custom DIY speaker stands: Flooring: Looks awesome!!! Hidden TV: Custom DIY desk:

very nice indeed!

Thank you! Dealing with my small booth/storage room at the moment. Soon I 'll get myself making some music at last!!!