k2j said:
I wonder when latency becomes a problem daisy chaining from out to in, out to in, out to in, out to in... anyone experience that?
Maybe a very small amount, that may alter the bass output a bit (could make kicks a bit muddy).
I had biggest problems with phase. At one point I took apart ALL my boxes to match their phases, but when I put them on a configuration of 10 boxes (seen in my avatar), I had to try and find the right phases for all the boxes (using a 8 channel signal processor). I always have to check all phases if I hook them up in a different place, because the space/room can do funny things too.
The thing is that most boxes are working as somewhat dipole. Non-scientifically one could call them "semi-open baffle" or "damped baffle". The box itself gives little more sensitivity and boosts the low frequencies, but the perforated back lets the pressure and most of the frequencies generated by the woofers out from the back. So the boombox radiates sound to both directions, of course less to the back. Also there is about -12dB lower level straight to the sides because the front and back soundwaves have different phase and they counteract each other. When you put multiple boxes on top of and/or next to each other, there can be changes in phase and directivity. In a perfect situation each box should have steplessly variable phase change of at least 0-180 degrees.
In my current configuration the 3 boxes on the right (not the top one) are daisy chained (line-in/line-out) but I had to be careful with those because Sharp GF-575 had higher sensitivity and Philips and Siemens boosted the line-out. So ->Sharp->Siemens->Philips was the most optimal choise. If I put them in a different order, the Sharp and Siemens would distort and Philips would't have "enough" level.
So when chaining, one should try and keep track of what the VU-meters are reading. A little distortion can be hard to notice, but if the box distorts a little because of too high line in level, the line out will probably have much more distortion. At least if the box boosts the line out level.
I suggest searching for old analog 3-4 -way car hifi crossovers and use them if hooking more than 4 boxes to one output. With a crossover, you can set the levels more accurately and with a good model, maybe use them as subsonic filter and cut the lower (35-50Hz, depending on boomer) frequencies out and have more output and less distortion on bass-heavy program.
On my configuration, I use Helix P-DSP with 8 channels and every box (minus the chained 3) is uniquely EQ'd and filtered so the output is as smooth and powerful as possible.
There went my few cents
