Feedback Destroyer -> logans. Madness?

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JohnA

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If someone were to suggest a few weeks back that I could use 'PA' sort of equipment to feed the logans I'd laugh at their face. Loudly :ROFL:

But hey, life is full of surpsises
I've recently got a Behringer 'Feedback Destroyer' FBQ2496 to control the room modes that can't really be absorbed. A nasty one is at 50Hz, bit too low for meaningful passive absorbtion.
So I thought what the hell, if such gizmos are OK for JonFo:bowdown: , they might be OK for me:p
The original plan was to use the two channels just for the subs. Only the parametric equaliser of course.

After a few hours with the room equaliser (free REW!) it became clear that the subs could not counteract the peaks created by the SL3s.
Thankfully I am bi-amping them, so I tried connecting the Behringer to intercept the signal after the panels, on it's way to the bottom part of the logans (and later feed the two subs as well).
This works very well actually, and since the SL3s have relatively low crossover point, all electrostatic clarity remains intact:music:

The bad news is that it takes many hours listening to test tone sweeps and fiddling with knobs until you realise that the task is much harder than you thought
I'm now bidding on eBay for another 'feedback destroyer' so I can use it for the big sub and trim the LFE signal as well.

The bottom line:
I am now a believer.

Low-frequency control without one of these gizmos is next to impossible.:rocker:
 
I do believe they are a great tool for sub intergration. Especially IB type subs.
 
I did toy with the IB idea, in the end I chickened out and didn't open a hole in the wall - instead built a no-compromise sealed enclosure for a 18" driver. The baffle alone is 2.5" MDF, over 60Kg weight:eek:

Frequency responce in the room according to REW software is attrocious though, without the parametric equaliser it is very much hit-and-miss.

But the surprising thing was how much better the frequency response of the logans themselves can become (biamping only, I wouldn't want the panel signal through anything avoidable)
 
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