+/- 12 V Power supply simple circuit?

[joensd]

So delta-f on the spreadsheet is the 3 dB down point from the peak (15dB-3= 12dB point), not the -3dB from the base of the profile?

Yes; again, look at the drawing/graph from Linkwitz.
Active Filters
Graph on the lower left.
The notch you want to synthesize is sort of the inverse of the resonance.

 

[tonescout]

If you want to just test it, a pair of 9V PP3 batteries will work just fine.

So just put one on + 9V and one reversed on -9V?

Will this change anything when I use the internal 15V that the amplifier has for it's preamp that I can 'steal'

Thanks,

 

[tonescout]

If you want to just test it, a pair of 9V PP3 batteries will work just fine.

I took out 2 connections from the preamp out and power amp in on RCA connectors, and tried this (something my brother used in the past for his home cinema) it did a job of removing room modes automatically , but it sounds weird/unmusical/detached in the bass with this in place. Plus it makes loads of background noise in the sub. Yuk

I will use these to plug in an active filter on a overboard with RCA females feeding the circuit driven by PP3 batteries to see how this works out

DSPeaker-Anti-Mode 8033