Helmholtz Resonators

Everything Else Humor
21
maniac said: Mine two are set to about 45-55Hz and other two I'm waiting for will be set to around 70Hz to get rid of nasty null I have.

How they are ?
Does they really help ?
My friend had two pieces of those.
Theirs chief engineer assured him that they are working for less than 50 Hz (the pick was in 45, if I remember correctly), simply it's doesn't have enough markup, but after setup & tuning, the measurements revealed that the peak remained almost unchanged.
He eventually sold them because he wasn't happy with the results.
22

@valer_valer it is true that the effectivity in frequency response is in my case, only about 1,5dB for one piece so about 3dB with two varibasses in corners. Measured on my peak of 45Hz. But it’s efficiency for reverb is very nice in my case.



frequency response:





and waterfall:







For my room of 22 square meter it is recommended to have 8 pieces of varibass - which is not possible as my listening room is also living room :slight_smile: So I have decided i will have to live only with four pieces. I’m now waiting for delivery of additional two varibasses soon, one super bass trap (to cancel 85 Hz null) and two super bass 90 foam corner traps. I hope it will be enough to tame the nulls and also the remaining reverb on 45-60Hz.

23

And It’s is the key to put tuned traps exactly into place where it is most efficient. For frequencies between 30 and 60Hz it’s in most cases in the corners (including floor/ceiling corners)


24

@maniac Looks good.

Mine is big corner bass traps (something like half a meter thick) from floor to ceiling, plus ceiling-walls side panels 12 mm thick. Extremely dry listening room :).

But my bass traps do not do a good job. It’s Basotect (melamine resin), with exceptional fire properties, but compromised acoustic one. May be I should try the varibass units instead …

25

I would maybe think rather combining them than to replace them. You current bass traps are probably broadband and in case your room is not overdamped I would not remove them completely. Varibass is working only on specific frequencies you setup, but over 125Hz it’s reflecting, not absorbing .

26

You’re right, but I’m afraid it’s just can’t fit together.

In any case, I have to try, thanks.