I have just read through this discussion thread quickly, so I am just barely informed. Perhaps someone with an A/B ‘scope and some RCA ‘Y’ connectors could do a simple test for us to determine if there is a 950 phase reversal problem. I would advocate this over “room listening” so that room effects are not a part of the test.

Source set-up: with either a sine-wave generator or a test disk playback set to play 60Hz, use a single output through a ‘Y’ adapter to give two in-phase signals. Add a second ‘Y’ adapter to the first ‘Y’ adapter to give three in-phase signals. Connect one of these signals to the Left Front input of the multi-channel inputs. Connect the second of these signals to the Sub input of the multi-channel inputs. Set the 950 to multi-channel mode with Analog Bass Management “off.”

Before testing the 950, directly connect the test signal to the ‘scope and check that the sine wave being used is ‘clean and nice.’ If any signal summing in the 950 or in the ‘A+B’ mode of the ‘scope shows and oddly shaped wave, then we are dealing with phasing other than at 0 or 180 degrees.

Tests 1 and 2, other connections: Connect the Sub output of the 950 to the ‘A’ input on the ‘scope. Connect the Left Front out of the 950 to the ‘B’ input on the ‘scope. First, look only the ‘A’ input on the scope (do not ‘A+B’ yet). Since the 950 will sum the 60Hz of the Left Front input with the Sub input, you will see the result of this summing on the ‘scope.

Test 1: Disconnect one of the ‘Y’ adapter inputs to the 950. If the amplitude on the scope drops, then you have shown that the two signals were in phase with each other as the inputs were summed. If the amplitude rises when one signal is disconnected, then the inputs were summed out-of-phase and disconnecting one of the inputs has taken away the cancellation effect, allowing the output level to rise. Assuming that with both inputs connected, the output is higher than with only one input connected, and that the sine wave still looks like a clean sine wave, Test 1 has a passing grade, meaning that the inputs are processed in phase with each other. If the output wave became oddly shaped (not a “nice” sine wave) when the two signals were summed, then the two signals are being summed somewhere between 0 and 180 degrees phasing with each other and we have found yet another problem.

Test 2: with the Analog Bass Management switch on the 950 set to “off” so that the 60Hz signal will be present on both the Left Front out and the Sub out of the 950, switch the ‘scope from ‘A’ only to ‘A+B.’ If the ‘A+B’ amplitude is higher than ‘A’ alone, without wave distortion, then we have shown that the outputs are also in phase. Test 2 is passed, meaning that the outputs are also in phase with each other.

Test 3, absolute phase: instead of the ‘B’ side of the ‘scope being connected to the Left Front output, connect the third leg of the ‘Y’ adapters to the ‘B’ input on the ‘scope. If the ‘A+B’ selection on the ‘scope provides a higher output than either ‘A’ or ‘B’ alone, then we have shown that the 950 provides an output that is in phase with the input while in the Multi-channel bypass mode.

If the inputs are in phase (Test 1), and the outputs are in phase (Test 2), then your listening will be OK regardless of whether there is any timing or phase shift seen in Test 3. Test 3 is only for the sake of “knowing.”

Why not test the difference between Multi-channel bypass and other modes? Because as long as any mode is in phase with itself, you only listen to one mode at a time, right? As long as the Sub remains in the same relative phase to the rest of the speakers in each mode, each mode by itself is OK. If one mode has a different phasing error within itself than another mode has, then “oops!,” we will not have consistency of speaker/sub phasing.

Oh, if you turned the analog bass management “off” for the testing, it may need to be turned back “on” again for your normal installation.

Remember, any phasing error between your regular speakers and your sub(s) produces problems only at frequencies being produced by both the regular speakers and the sub(s) simultaneously. Also remember, since the regular speakers are spread around the room, your subwoofer(s) can’t be exactly in phase with all your speakers at once anyway!

Bottom line: since we were here to talk about the 950 … if Tests 1 & 2 turn out OK, then any realized error is not because of the 950.