dbx DriveRack PA2 with REW EQ

[iccir]

I use REW in combination with my dbx DriveRack PA2. Recently, I've been trying to reverse-engineer how PA2 settings correspond to REW settings.

Is there any way to define a custom equaliser, or to request the addition of the PA2 to the equalisers?

The PA2 supports 8 PEQs per output in addition to 8 for the "Auto EQ". In a single stereo pair environment, this gives you 16 total PEQs to play with. Each PEQ can be of one of three types:

Type: "Bell"
Frequency: 20Hz to 20kHz
Gain: -20dB to 20dB
Q: 0.1 to 16
Q uses the same formula as the rePhase setting:
Bandwidth = sqrt(gain)*centre frequency/Q

Type: "Low Shelf" and "High Shelf"
Frequency: 20Hz to 20kHz
Gain: -20dB to 20dB
Slope: 3 to 15
Frequency and gain behave similar to that of "LS" or "HS" in Generic.
According to the manual, slope is in dB/octave. However, I've been unable to figure out the exact formula - it doesn't appear to be the standard RJB Cookbook ones.

Frequency	Gain	PA2 "Slope"	Approximate REW Q (Generic LSQ/HSQ)
1000Hz	20dB	15	1.0
1000Hz	20dB	3	0.327
1000Hz	6dB	3	0.489
1000Hz	6dB	15	1.471

If anybody has a clue as to how to translate the PA2 Slope into RJB or REW Q values, any help would be appreciated

 

[John Mulcahy]

For the shelf filters you may be able to use the RBJ equation:

1/Q = sqrt((A + 1/A)*(1/S - 1) + 2)

with S = (PA2 slope)/12, I have seen S=0.5 shelf filters referred to as 6 dB slopes before.

A configurable equaliser is on the todo list.

 

[iccir]

Thanks John!

I tried S=(PA2 slope)/12, but the numbers still aren't lining up. I'll continue to play around with it. It's great to hear that a configurable EQ is on the list! Please let me know if you need me to test anything in regards to the PA2.

Cheers!

 

[nickpsaltakis]

Hi, i use Dbx 360 Venu... So yes an dbx eq in the eq section would be really helpful... Thanks