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IraSeigel
11-13-2008, 05:45 PM
I'm experimenting with using the Frequency Analyzer as a SAC plug-in.

My calibration mic is patched into an unused input and that input strip is assigned to Output 8. I've inserted the FA as an effect pre-fader on Output 8, and I can control the level of the signal into the FA using the fader on the input strip. All works great. FA adds about 4% CPU load on my older T40 Thinkpad.

I'm doing an event today in a large, ambient hall with many open lavalier and handheld mics, and I'm intending to use the FA to indicated possible feedback points. The mic is sitting in the empty room and picking up the air conditioning noise, etc., with many of the FA's upper frequencies registering input.

My question is this: Is there a way either with Bob's FA or another one to take a reading of the background noise and then use an "inverse" of that reading to flatten out the FA's curve? This would, in effect, calibrate the FA to the empty room and the calibration mic, and so once the lavaliers were open and possibly creating feedback, the FA would be registering THOSE frequencies and not the pre-existing background noise.

If not an "inverse" function, then perhaps some other way of zeroing the FA's reading in an empty room.

I don't think I've ever seen this function in any RTA, so I'm just wondering if it's possible and a useful feature to have (not necessarily in Bob's).

Cheers,
Ira

Bob L
11-13-2008, 07:01 PM
Well you could just use my or any graphic eq plugin in front of the FA and adjust the eq to flatten the FA room reading... now anything else is the mics... but not really... because the room noise will not really contribute to any feedback problems introduced by lavs taking off at a certain frequency.

Personally, I am thinking there may be a flaw in your logic here. :)

Bob L

IraSeigel
11-13-2008, 07:11 PM
...

Personally, I am thinking there may be a flaw in your logic here. :)

Bob L

Hmm. Possibly. I've worked 12 days straight. :o

Ira

Carl G.
11-19-2008, 10:36 AM
I'm experimenting ....
My question is this: Is there a way either with Bob's FA or another one to take a reading of the background noise and then use an "inverse" of that reading to flatten out the FA's curve?

If not an "inverse" function, then perhaps some other way of zeroing the FA's reading in an empty room.

Cheers,
Ira

Ira... I just reviewed this thread... you might be interested in:
voxengo - "Curve EQ"
http://www.voxengo.com/product/curveeq/

Trackzilla
11-27-2008, 04:10 AM
Curve induces latency and hence is not happy in SAC, the Gliss EQ from Voxengo however does not, I have played with the demo & it ran fine, it also has spectral display...they also have a freebie plug that is just the spectral display part of Gliss called SPAN:
http://www.voxengo.com/product/SPAN/