If I run a -12db/octave HPF set at 60Hz, and then employ another HPF with the same setting, am I dropping by -24db/octave, or just doing the same thing twice?
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Good question...is this a real-life scenario? Case in point: got a HPF (~40 hz) at the front of my signal chain and another component at the tail-end with a ~45 hz HPF.
Riis
Yes. I have a Broughton HPF and then there is one on the Acoustic Image amp. I'm asking about the effect of using them both.
Not a clue but it brings up some interesting possibilities / opportunities:
*I hate redundant systems when absolutely wasteful...this is not IMO. Solo each HPF...which sounds better? Both my HPF's reside on my pedalboard.
*If drawing your DI signal from the amp with the HPF engaged, re-assign the Broughton to your compressor's sidechain if so equipped.
*The Broughton is a god-send if you ever have to throw your board in front of a foreign (unknown) backline or the soundguy taps your pedalboard's DI for FOH.
Sorry I couldn't add anything to the original question but stuff like this gets me thinking...a practice I try to avoid.
Riis
Doesn’t the AI HPF come AFTER the preamp and EQ section?
I think that’s how it works if I remember correctly.
If that’s the case, you could use the Broughton at the very beginning of the chain so that the AI never even gets those subby lows, and it would free up some headroom on an already very clean amp.
I don’t really see why you would need the built in EQ at this point, unless it’s an awful stage and you want to send a Pre-EQ signal (Broughton still used first in the chain) to FOH but roll out even more lows on your stage rig.
That's pretty much what I'm doing. Bass>Broughton>Keeley compressor>Amp. Yes the Filter in AI is post EQ.
I've been very impressed with the Broughton. I do a lot of musical theater which means in a closed space pit and the pits will sound 'boomy', some even have a resonate pitch, so the HPF helps a lot.
I was just wondering if the Broughton clears up the low end and the AI has nothing to filter out... or does the AI fliter take out more? Either way, there's not a problem. Everything is really clean and clear. I was just curious.
It all depends where you set them.
You could get some 12+12 filtering like the FDeck Series 3 offers if you were to set the Broughton at 40Hz and then the AI at 40Hz or above. If you filter lower on the Broughton and higher on the AI, depending on the compressor settings and EQ between the two, you may run into some interesting/useful resonant frequency bumps.
If you filter at 80Hz on the Broughton and then at 40Hz on the AI, the result would be pretty negligible with everything flat and at unity in between.
You could get some 12+12 filtering like the FDeck Series 3 offers if you were to set the Broughton at 40Hz and then the AI at 40Hz or above. If you filter lower on the Broughton and higher on the AI, depending on the compressor settings and EQ between the two, you may run into some interesting/useful resonant frequency bumps.
If you filter at 80Hz on the Broughton and then at 40Hz on the AI, the result would be pretty negligible with everything flat and at unity in between.
In my understanding, the latter… the slope of the attenuation will be steeper (24db per octave).
I understand that there might be some resonant frequency effect if both filters are set close enough...as pointed out by Pat.
What I would do in case I had your gear, I would set the Broughton for FOH (between approx. 25 and 50 Hz) and set the filter on the amp to protect my speaker(s) and get rid of the rumble on stage (between approx. 50 and 80 Hz).
Good luck!
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Azure Skies
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You are dropping by -24 dB/octave below the cutoff frequency. There won't be any resonance with my HPF.
If you set them at different frequencies, say 25 Hz and 50 Hz, you will have a -12 dB/octave slope below 50 Hz, and an additional -12 dB/octave slope below 25 Hz, meaning, the slope will be -24 dB/octave below 25 Hz.