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Discussion Starter #1
I've read the 17+ pages on waterfalls, but I'm still not sure what result I should be trying to acheive. Is there a consensus view ?

Without posting my waterfall plot, all frequencies are less than 300ms ~200ms except for around 20hz, where it looks like there is a little ringing. I remember reading that this wasn't necessarily a bad thing at this frequency, or am I mistaken ?

Thanks for the input.
 

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Since we are dealing in pure abstraction without any reference.....

A consensus view regarding 'what' exactly?

Do you have any high gain persistent ridges that extend outward in time?
Typically they correspond to a peak in gain.

If so, those are the modal anti-nodes - the resonances that occur at that point in space that are determined by the room geometry and the acoustical impedance of the boundary -= and that is what various methods of treatment, ranging from relocating the sources, the listening location, or mollifying the geometry of the massive boundaries, or velocity or pressure based traps seek to remediate.

As far as some abstract 'time' - without correlation to gain, it is itself of little use as a baseline.
 

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Discussion Starter #4
SAC, thanks for your reply.

What I meant by consensus view was is there a generally agreed maximum time for which you want frequencies to decay.

Anyway a few pictures will probably tell a thousand words.

Here is the room. Sorry pics are a little dark.



Here is a picture of the front before carpet. You can see the stage here.




And here is the waterfall.



The room is extensively treated, and was designed by Dennis Erskine. Unfortunately the room is on the smaller side at 15' x 13'. I wasn't expecting perfection with these dimensions, but I would like to see what is going on.

Cheers
Jamie
 

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A good waterfall graph should have the signal 50 dB or more above the room’s noise floor. Looks like you probably have enough signal, but you should move the graph floor down to 30-35 Hz.

That said, it looks pretty good. The only “problem” area, if there is one, is below 40 Hz. Not much you can do about ringing down that low.

Regards,
Wayne
 
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