Re: DBX Driverack PA question
There are shelving filters. You can set the highest or lowest filter on each output to be shelving, it's an option on the main EQ screen before you go into each filter.
A huge issue I have with the 240/260/PA/PX line is that they do not actually bypass the crossover filters when you scroll them to 'out'. All it does is change the screen to show that it's off, when the crossover filter is still in, just at the extent of the audible range. While the filter may not affect the magnitude response much, it still causes a MESS to the phase response because the filter cannot be bypassed. So if you intend to bypass the crossover, because maybe you're connecting that particular band to a powered speaker or something, then change the crossover to the lowest order filter present, the 6dB Butterworth.
Yes, I've measured this to confirm.
Silas,
Regardless of the DSP used, the A/D and D/A will introduce latency.
An engaged filter may add to the latency, but to find out how much in any case requires measurement.
Since measurement is needed for precise alignment (to avoid a MESS in the phase response) of a powered speaker using any type of DSP, I don't see that as a huge issue particular to the DBX lineup.
As a user of the DRPA, I have no sonic complaints (other than the shotgun noise when powered down before the amps) though the limited amount of PEQ filters means it is hard to correct truly awful speaker designs, and the limited delay time won't allow super long bass horns to be time aligned.
Polarity reversals on each band would be useful, and it would be nice if the input to output were not polarity reversed, but it is cheap and reliable.
Like any digital device with a tiny interface it is difficult to adjust until you become familiar.
Being familiar with the DRPA and other DBX DSP, I had similar problems John Chiara mentioned in the OP when I first tried adjusting the Behringer DCX 2496.
I would agree with Dick Rees that the DRPA is often misused, but that is commensurate with the knowledge of people generally at the price point of using a DRPA.
Anyone unfamiliar with speaker parameters, time and phase alignment, and measuring equipment will not be capable of good results even with the best available DSP, and generally will make stupid, horrible sounding mistakes.
And then blame the DSP, speakers or amps for their ineptitude.
Art