I'm not sure how many purists are out there in Outlaw Land who still enjoy pure, unadultrated 2-channel stereo.

After living with the 970 a few months, I can tell you that there is a noticeable difference in soundstaging between bypass and stereo modes. I guess this is a testament to the how little the signal path is manipulated in bypass mode. My thanks to Outlaw for this option.

Converesly, it appears that in stereo mode the digital bass management circuitry has a noticeable impact on imaging. In particular, soundstage depth is reduced and proper centering of vocals is altered. This has become much more
noticeable since I upgraded from my aging Snell Type C floor standing speakers to a pair of Quad 11L monitors.

For example, a recent experiment with a CD of female vocals (Sade, Love Deluxe) showed that while in bypass mode, a pinpoint image of Sade's voice was rendered perfectly between the two speakers. Close your eyes, and you could picture her singing right there.

However, when switching to stereo (not 5-channel mind you), the perceived size of her head widened substantially and the vocal image was no longer well anchored to the center-point between the front speakers. Even my wife, no audiophile, could clearly tell the difference and prefers listening to CDs and LPs in bypass mode.

For most music, running in bypass mode gives me what I'm looking for -- good two-channel performance from my 970. But for those times I want a little more ommph in the bass, I wish I did not have to trade off good soundstaging when I engage the subwoofer.

I have experiemented with various crossover settings to see if this will have an impact. While these experiments did show at what frequency the subwoofer and monitors blend the most seamlessly, they had no impact on soundstage/imaging performance.

Is this an area where firmware upgrades could offer some improvements?

Very interesting write-up. Since I don't have an 970, I can't speak to how the two modes compare. Two thoughts do come to mind though, and both might be interesting experiments for you. One is to ask if you were still using the analog input when you switched from bypass to stereo - if so, it's possible the ADC is actually the culprit in the soundstage changes rather than the bass management, and using a digital input could yield different results. The other thought is to ask if you're using the 7.1 Direct input currently. If not, you might try running the left and right channels from your CD source to the left and right channels of the 7.1 Direct input (also known as the DVD input's left and right channels) and set the 7.1 Direct input's bass management switch to "HPF/LPF" to apply the analog crossovers so that the subwoofer gets in the game for analog sources.

Wow, as usual Gonk, you've got a lot of good suggestions.

What I'm doing now is running analog out to the 970 from my CD player. I assumed the performance from the DAC, etc. in my Cambridge Audio 640C CD player was an improvment over the digital processing available in the 970, but I could be wrong. I know that may not the case with the 990, which has superior digital processing than the 970 (if I remember correctly). Anyway, I could hook up the digital output and do an A/B comprison to verify.

As to the 7.1, HPF/LPF option you described, is that available only in the DVD input? With a DVD player currently hooked into the DVD input I would prefer not sacrficing it to the CD player... Or am I following your train of thought correctly?

You may want to hook up the Cambridge's digital output just to compare stereo with digital input to analog with bypass - analog input and plain stereo mode is a pretty convoluted signal path. I've heard good things about the Cambridge, so I suspect your original assumption (better DAC in the Cambridge than the 970) may well prove true, but the most accurate A/B comparison will be to let the 970 get a digital input.

The 7.1 Direct input can be accessed separately from the DVD input - it just happens to share the left and right analog channels with the DVD input. You can select "DVD" from the remote and still have that using the DVD player's digital connection and then select "7.1 D" from the remote and get the CD player.

Gotcha. Thanks. I will give it a try and post the results.

I was re-reading my manual last night in light of Gonk's recommendations. In the section on the Bass Management Selector Switch (pg. 8), it states "Three position toggle switch for selecting how the Model 970 routes bass signals for the DVD 7.1 multi-channel analog inputs ONLY." [emphasis added].

If this switch only applies to this input, does that mean that for all others, bass managment is handled digitally, regardless of where the selector switch is positioned?

If that is the case, I think routing the CD player through this input and selecting the HPF/LPF analog filter might work, as 80Hz is my crossover-point of choice for the front speakers.

Still waiting for my replacement tweeter, so I have not had a chance to experiment with any of the above.

Correct, the switch only relates to bass management for the 7.1 Direct input. All other bass management is handled digitally (as is true of any modern surround receiver or processor), and analog stereo sources set to "bypass" receive no bass management at all since the signal stays in the analog domain all the way through (thus skipping the digital bass management).

Hmmm...even though the manual states that the three position toggle switch is for the 7.1 inputs only, I'm sure I played around with this a few months back on my 1070 and noticed that it affected the other analog inputs, or at least the CD input. Specifically, with my DVD/CD player connected via the CD analog inputs there was a bass signal sent to the sub in bypass mode with the switch in the HPF/LPF setting but no output was sent to the sub with the switch in the bypass position. Anybody else experience this behaviour?

To your point John Galt, I recall being advised by the folks at Outlaw to set the switch to the "digital" position, as if by doing so it would employ digital bass management for all inputs. yet tha manual clearly states it is only for the 7.1 analog inputs.

As to your results with the input selectopr settings, I'm at a loss for an explanation.

Oh, and... Who is John Galt?

I have a 950, not a 970, but I ended up getting a Paradigm X-30 active analog subwoofer crossover ($120 used) so that I could use the 950 bypass mode and still use a sub. It works pretty well.

I can also hear a difference when bypass mode is on. I really didn't want the signal going A->D->A just to go through a crossover.