Question about SACD .1 bass.

[HiRes_PR]

Your points are well-taken but dependant on knowing what the producers did with the mix. Most of the music I listen to is not produced that way and bypassing BM is a direct route to what was put into the mix. In some cases, BM is presumed by the producers but how can you know?

As for your last point, the LFE SHOULD already have a LP filter in its production but, again, it depends on the mix.

However, one cannot assume that fiddling with the parameters of BM will apply to any and all recordings.

Kal

My point is that you no one knows what the producers really intended as you previously said. Mixing techniques, regarding to bass placement, varies from disc to disc.

Also, not all LFE signals had a LP filter in the production line. Even in DIRECT mode you should set the Sub's LP filter to the main L/C/R speakers bass limit to avoid bass overlapping.

And finally, well executed Bass Management helps to achieve a correct and balanced sound from home theater speakers setups regardless what the mixing engineer did. The problem here is to make it right and this is where almost all player fell short. But still not impossible.

 

[Kal Rubinson]

My point is that you no one knows what the producers really intended as you previously said. Mixing techniques, regarding to bass placement, varies from disc to disc.

Also, not all LFE signals had a LP filter in the production line. Even in DIRECT mode you should set the Sub's LP filter to the main L/C/R speakers bass limit to avoid bass overlapping.

And finally, well executed Bass Management helps to achieve a correct and balanced sound from home theater speakers setups regardless what the mixing engineer did. The problem here is to make it right and this is where almost all player fell short. But still not impossible.

Well, I guess we do not disagree fundamentally but, rather, on initial approach to the problem of uncertainty. I tend to regard bass management as a system-related variable since most of the discs I use do not require it and, in fact, many lack LFE or only duplicate main bass in the LFE. As you point out, the issue of reduplicating the bass is a stealth issue of which most are uninformed due, mostly, to the lack of useful information.

Kal

 

[HiRes_PR]

Well, I guess we do not disagree fundamentally but, rather, on initial approach to the problem of uncertainty. I tend to regard bass management as a system-related variable since most of the discs I use do not require it and, in fact, many lack LFE or only duplicate main bass in the LFE. As you point out, the issue of reduplicating the bass is a stealth issue of which most are uninformed due, mostly, to the lack of useful information.

Kal

You're lucky that the material you listen to has bass duplicated in the LFE.

But a lot of Pop/Rock and some Classical discs have different bass signals in the LFE vs Mains. A clear example is KaJe DVD-A. It doesn't have any bass on the 5 main channels. All bass is located in the LFE. Also, there's a difference in bass energy between the 5 mains and the LFE on Telarc's Stravinsky Firebird Suite conducted by Paavo Jarvi (SACD-60587). Bass is really stronger and deeper in the LFE vs the rest of the channels.

I tested myself by removing the LFE cable from the player to my external Bass Management controller for comparison. Bass on some disc is duplicated in both mains and LFE as you stated. But on some, regardless of the type of music (even Telarc), the LFE has a deeper bass to be handle by a subwoofer (power and frequency extension in mind). A frequency extension that can cause choke on most "full range" speakers.

 

[ssully]

I always assumed that the .1 LFE bass channel, when set to "direct", only accepted the input which the person who mastered the disc intended to be there.

No, direct only means that the sub's own crossover is bypassed...the option is there because you wouldn't want, say, a subwoofer input signal that has already had all its frequencies above 100 Hz filtered out, to be subjected to
a filter in the sub set to attenuate frequencies above 80 Hz -- that would leave a 'hole' between 80 and 100 Hz in the sub output.

Older subs that don't have a direct option, avoid this problem by setting their
crossovers to be significantly higher than the one already used on the incoming signal (e.g., bass input to my sub -- a 10" Velodyne F1000, as it ahppens -- is already filtered above 80 Hz by the components upstream of it...so I have set my sub's filter above that, to 125 Hz).

I found this true on most of my DVD-A's, and DVD-V's. Recently I purchased a universal player, the Tosh SD 4960, and have found an increased bass response with quite a few SACD's I have purchased. . I got some James Taylor SACD's yesterday, and the bass hurt my ears. I doubt the person who mastered the disc intended this. Any ideas? I use a Velodyne 10" subwoofer; with full speakers for the other 5 channels.

Check the level adjustment that the Toshiba player is applying to the analog sub channel output. It may be on maximum, and that may be louder than what your previous player output. It's also possible the the Toshiba outputs SACDs at different levels than other formats, or that it applies a different crossover to SACD than other formats (and I suspect it won't apply a crossover to *any* formats unless you have some speakers set to SMALL).

 

[Guy Robinson]

I always assumed that the .1 LFE bass channel, when set to "direct", only accepted the input which the person who mastered the disc intended to be there. I found this true on most of my DVD-A's, and DVD-V's. Recently I purchased a universal player, the Tosh SD 4960, and have found an increased bass response with quite a few SACD's I have purchased. . I got some James Taylor SACD's yesterday, and the bass hurt my ears. I doubt the person who mastered the disc intended this. Any ideas? I use a Velodyne 10" subwoofer; with full speakers for the other 5 channels.

What happened to just turning it down for that disc? That is what I do. That's what the volume on the sub is for.

 

[Kal Rubinson]

No, direct only means that the sub's own crossover is bypassed...

That's not what I mean by 'direct.' The DIRECT I refer to is the setting on the player (or receiver) that bypasses bass management and distance compensation. No setting on the sub can alter the distribution of signals to other channels.

This may explain why we sometimes talk across purposes as we are speaking of different phenomena. Again, setting the player and/or receiver to 'direct' assures that all the channels are directed as the producer intended. Setting the woofer to direct or bypass only takes its crossover out of the issue.

Kal

 

[ssully]

True; I assumed he was talking about his sub because of questions like
"I think you are suggesting changing the setting on the subwoofer from "direct" to "bass management?"

 

[ct]

First, thank you for the advice and replies. I've been out of the country for a few weeks, and just read the recent ones. I was talking about the settings on my Velodyne Sub, a CT 100. I went into setup on the DVD-player and, low and behold, found that some of the speakers were set to "small", which was not how I set them up. Perhaps a power outage, or something. Anyway, Resetting them seems to have improved the situation (haven't checked all of the problem discs). As for setting the bass level on the subwoofer for each recording - that seems to me to be terribly inconvenient, as my sub is out of sight behind a chair - and one would presume that the producers of the disc would have an "ideal" level . . .

 

[Guy Robinson]

one would presume that the producers of the disc would have an "ideal" level . . .

That's not the way I look at it. I know what I like and I set it that way. I don't care what the producer's intention was frankly. My sub is easily accessed so it's not a problem to fiddle with the knob.

 

[ct]

I tried James Taylor's "October Road", which caused me to start this thread. What a difference - no excessive base. Resetting the speakers to all "large" seems to have made the difference.