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.

quick digression on a related topic if I may...

has it been definitively established that in bypass mode the unit's DACs are bypassed entirely? I have an external non-OS DAC I want to use with this and would like to be sure the signal remains in the analog domain once it gets to the Outlaw (and not processed by the DACs or upsampled, etc).

Thanks!

Yep. In "bypass" mode when using an analog input, the 990's DACs are completely out of the loop. (I make that qualification of "when using an analog input" because "bypass" is an option when using digital inputs, in which case the 990 still uses the digital input and you of course still use the 990's DACs.)

Okay, my system is back online and so I tried the suggestions laid out by Gonk. Based on a few A/B comparisons, the CD player using the Cambridge's DAC (via analog out plugged into the 970s 7.1 front L&R inputs) sounds noticeably better than the digital out on the Cambridge and the signal processed by the 970's DAC.

The 7.1 bass management setting is set to HPF/LPF. When you select 7.1 on the remote, the 970 displays "Bypass." This initally confused me, as I always associated "bypass" with "bypass mode," in which the digital bass management is out of the loop, the sub is disengaged and the front speakers run full range. (I think in this particular 7.1 set up, the "bypass" display must refer only to the fact that digital bass management is being bypassed, as the sub was defintely operating during playback).

The HPF/LPF setting defaults to an 80Hz x-over, which I prefer anyway, so I am happy with the results for far (I just wish there were an addtional input like this I could run my phono preamp into!)

Still to be tested is an A/B comparison between this current set up and the CD analog output in pure "bypass mode" (i.e. without sub).

I am hoping the 7.1 set up with the signal in the analog domain will result in less degradation of the soundstage compared to the convoluted analog/digital/analog path I was using before. But I will report back the results.

I concur about the "Bypass" message - the 970's simply saying that the analog input is bypassing any digital processing, but it is not doing anything silly like downmixing to stereo.

. . . which indeed is a nice trick, very eye opening.
I'm glad to read this thread. I will see how this affects the overall performance when playing familiar CD's. I prefer to have "bypass" as the mode but until now was dissapointed I was getting no signal from the sub out.
Thank you again.
Beakman

Beakman:

After living with this set up for a few days, I can tell you I am quite happy with it. I still have not tried an A/B comparison between the 7.1 input and "pure" bypass mode in the CD analog input. But at this point, the sub is so well integrated and things sound so nice, I don't envision going back.

Next, I'd like to see how the 7.1 input sounds with my phono stage.

Videodrome,
I can say there is a definite improvement with my system too! The outboard imaging is the most notable. Now that I have a "System Sound Baseline", I can better work with (listening) room environment. First will be a large mirror on a side wall above the sofa, to make up for its black-hole sound sucking characteristics.

I'm resurrecting an old thread, but I wanted to report a pleasant surprise regarding the use of the HPF/LPF x-over setting in analog bypass mode.

Since my last post on this thread, I have been swapping my phono stage and CD player output cables between the 7.1 inputs.

Over the weekend, I hooked the phono stage back into the "AUX" input, switchhed to "BYPASS" and, though I was expecting a full range signal to my mains only, I was ecstatic to hear the sub going. So then I tried the same thing by re-hooking my CD player back into "CD," and bingo, the sub was engaged.

Evidently, if the toggle is switched to HPF/LPF, ALL analog sources played in "BYPASS" mode will activate the sub.

No more switching cables.

I am a very happy camper.

Now that is a slick discovery, Videodrome - and one that I don't remember hearing about previously.

hey gonk, not only do i love stereo i only am using an old adcom stereo power amp to run my 970, no fancy (and expensive) 7 channel amps for me! i dont understand how the emphasis on audio has changed from listening to music (which sounds much better in stereo) to listening to raindrops dripping behind your head when watching movies. however i am curious - just got my 970 for xmas, havent even hooked it up yet, but since i'm running stereo (i will use bypass) and just two speakers have you fooled around with VR (virtual reality) dolby when watching movies?

ps my old rottwieler's name was gonk.

I've never used the Dolby Virtual Speaker stuff, since I already had surrounds before having access to this sort of processing. It's one of those things that I just suggest giving it a try to see what you think of it.

There's an old 486 tower PC sitting in the attic that ended up being named "gonk" back in college because of its similarity to the Star Wars droid. I borrowed the name as my screen name a few years later. It's a good pet name, too, though - could see it for a rott or for a big cat like our persian or maine coon...

actually go out and rent the old "elvira" dvd (the original) and you'll see where gonk comes from. pretty decent movie too suprisingly, thumbs up from siskel and ebert.

Ratso - which movie are you speaking of?
http://www.netflix.com/Search?v1=elvira&search_submit.x=17&search_submit.y=8

I've seen the Elvira movie but don't recall where gonk cropped up - might have to watch it again one of these days. In my case, gonk comes from:

yup thats it, elvira mistress of the dark. long time viewers of the show (on tv) might remember her poodle on her lap with a pink mohawk, that was gonk.
watch the movie to learn more about gonk, including a big suprise with him at the end.

ok so actually i lied, it's really gonq, not gonk in the movie.