I am looking to integrate a miniDSP 2x4 into my system to act as an advanced low-pass filter for my subwoofers. Right now I'm just using a pair of simple 70hz FMOD low-pass crossovers in front of my subwoofer amp to do the job, but the results are barely adequate and offer me no advanced control of the crossover slope, etc.
Ideally I would like to put the miniDSP 2x4 in the same spot the FMODs are now, right before the inputs of my subwoofer amp, and not touch anything else. The potential problem is that anything going through the miniDSP 2x4 goes through an ADC -> DAC conversion (because processing is done digitally) and this results in an added delay of 1.2-2.5ms depending on what sort of processing is being done.
This delay is not an "issue" in most cases because, as far as I can tell, in all of their guides they show the main speakers being run through the miniDSP 2x4 also, even if no processing is being done on the main speakers. This would subject the main speakers to the same delay. An example from one of their guides:
Unfortunately, I could not setup my system like this even if I wanted to. My Yamaha C-80 preamp has 2 sets of pre-outs, one normal and one inverted, and I use this to run 6 amps total, 4 bridged and 2 in stereo (one of those stereo amps being the amp that powers my subwoofers). This is beyond the scope of what I could run through the miniDSP. I'm also not sure that subjecting all of my mains to an unnecessary ADC -> DAC conversion would be something that I would want to do anyway. I would like everything other than my subwoofer amp to remain directly connected to my preamp, bypassing the miniDSP.
So now, down to the real question. What is this 1.2-2.5ms delay going to do for me? If my subwoofers are 1.2-2.5ms behind my mains, is that even going to be noticeable? Does this sound like a deal-breaker so to speak?