It doesn't. No pre/pro does. And, get this: even for pre/pros that do simple 5.1 analog pass through: even if you adjust phase correct for DD/DTS/CD if you're using a coax or optical connection to your pre/pro, you still might not be in phase for the 5.1 analog inputs, even if you have the player setup as "all large", "sub on".

BTW, the phase between the mains and sub *more* depends on the slopes of the high pass filters (to the speakers) and the low pass filter (to the sub), and not so much the crossover freqs themselves.

The best suggestion I can offer you, is to pick up the DVD-A setup disc offered by Chesky, "The Ultimate DVD Surround Sampler & 5.1 Setup Disc". This disc has DVD-V and DVD-A phase tests that at least you can characterize your system with.

Since we are talking about phase, and wrt the 950... I had previously reported that the 950 reversed the phase of the 5.1 analog inputs when using its analog 80 Hz crossover with respect to the internal digital crossovers (for DD/DTS/CD). I now know that what the 950 does is unknown. What I do now know, is that if you are using a Pioneer player (the 45A and 47Ai at least), and you compare phase out of the analog inputs vs going digitally to a pre/pro, *then* you are already out of phase. I.e., using the analog outputs on the player, even if "all large", "sub on", the phase relationship between the mains and sub *is* different than going digitally to a pre/pro. I had assumed it was the 950, but it's the player. What I don't know, is how this works with any other DVD player's 5.1 analog outputs...

Theorectically, "all large", "sub on" does not do anything to the phase relation between the sub and mains. But most digital crossovers use a 24 db/octave low pass, and a 12 dB/octave high pass filter, and, usually you get a 90 deg shift for every 6 dB/octave of slope. So *that's* where the *difference* in phase comes from, between the analog outputs on a player, probably *any* player, and a pre/pro using its digital crossovers.

And to confuse things even further, obviously some players do have BM for SACD and DVD-A, but those slopes might not be the same between SACD and DVD-A, or even the same as what the pre/pro is doing!

I'm just surprised that more people and HT mags haven't picked up on this...

Now, there actually are (at least) 2 solutions. One, and I think some Anthem pre/pros do this, is to run "all large", "sub on" to the pre/pro, have the pre/pro digitize those inputs, and then use the same crossover scheme as for DD/DTS for DVD-A and SACD. This is a kludge IMO, because that extra A to D, processing, and D to A conversion *will* affect the sound quality. The 2nd is ... i.Link. You deilver everything to the pre/pro in its native digital format, and then the pre/pro can apply the same exact BM to everything.

I'm hoping that the next Outlaw pre/pro has i.Link...