sonotube diffuser

[bobmurphy]

someone has told me that a sonotubes are more efficient than flat panels ( to be honest i'm not 100% sure whether they were referring to absorption or diffusion qualities, but i think they meant diffusion) - so can anyone confirm or elaborate on this - are they very efficient and which are they mainly used for; absorption or diffusion ? ( i have only seen them being used as bass traps on this site, at least that's all i could find )

ultimately what i will need is economical/value for money diffusion ; and i think the person was saying that sonotubes were more efficient at this than polys

[gullfo]

sonotubes as in concrete forms - there are a number of ideas floating around on how to use sonotubes for Helmoholtz traps, diffusers, partial cut-aways for absorber/diffusers ala TubeTrap clones. i think with the right engineering and usage, they can play a role in acoustic treatment. i don't think they replace polys or rigid insulation absorbers and they're not going to provide some magical solution to a room...

did you ever get a response on the RT60 from the church acoustics forum? i saw they were vacillating on a hard number

[bobmurphy]

no it seemed to be too difficult

[gullfo]

i'm guessing then the approach should be go with more RT60 than less and see how it works. if it's too much add more absorption. while the points on the church forum made about confusing the people on the stage with higher reverberation than the stage, i'd still tend to make the stage dryer and make sure to terminate the back end of the church.

[bobmurphy]

edit: thanks for that

any comment on this ? ...... someone who knows a lot about church acoustics is recommending a completely different approach - zero absorption ( other than the carpet floor and the congregation in padded seats ) but a very large amount of diffusion to "make the bass travel further around the room" ( i think that's it anyway ) which ( if i have this right ) is supposed to have the effect of reducing (or apparently reducing ) the bass rt60 .... it sounds good but i haven't seen it discussed much ... to be honest i can easily understand the use of absorption and trapping, and i know what diffusion does but i cant really imagine how it could ever be more important than absorption and trapping

[AVare]

Church forum? I cannot seem to find it. Is it buried in a subforum?

Andre

[gullfo]

it's another site: http://www.jdbsound.com/cgi-bin/discus/show.cgi?5/349

i think if your space was larger and/or the ceiling was configured differently, then i think the diffusion approach would be a good way to go but i think the compression ceiling effect isn't going to have the desired effect with diffusion using hard devices. i think the scattered absorption approach is something you can "tune" to get the room response the way you want and is manageable with your budget and timeline. i'd still trap the corners and put bass trapping behind the stage and on the back wall to ensure even termination.

[AVare]

Thanks for the link Glenn!

Andre

[FLZapped]

someone has told me that a sonotubes are more efficient than flat panels ( to be honest i'm not 100% sure whether they were referring to absorption or diffusion qualities, but i think they meant diffusion) - so can anyone confirm or elaborate on this - are they very efficient and which are they mainly used for; absorption or diffusion ? ( i have only seen them being used as bass traps on this site, at least that's all i could find )

ultimately what i will need is economical/value for money diffusion ; and i think the person was saying that sonotubes were more efficient at this than polys

Sonotubes can be made into polys by splitting them in half lengthwise. They would be used for diffusion.

-Bruce