5.1 Input Bass Managagement in Receivers (1 Viewer)

[JohnThompson]

I am in the market for a new receiver. I have the Pioneer DV 45a SACD/DVD-Audio Player, so I need bass management for DVD-Audio (and it wouldn't hurt to be able to have a variable crossover for SACD). I would rather not use the Outlaw ICBM, since I cannot compensate for speaker distances with it.

Could someone help me out with a list of receivers that perform bass management on it's 5.1 (or 7.1) analog inputs?

I know the Denon 5803 does, but it is a little out of my price range (I am in the under $1500 market).

Does one exist?

Thanks!

 

[AaronBatiuk]

You may be disappointed with receivers that do bass management, especially for SACD. They all convert the audio to PCM, usually at 48 or, if you are lucky, 96 kHz sampling rate. The A/D converters in a receiver are not as good as those used in recording studios for several reasons, cost being just one. The extra generation of A/D-D/A conversion adds noise and introduces artifacts in the treble due to the analog anti-aliasing low-pass filters necessary for both converstions.

Let's not debate whether DSD (SACD) or PCM is better, but by putting your SACD audio through a receiver that converts it to PCM, you will get the worst of both worlds and the best of neither!

For SACD, you should use either analog bass management, or some form of true DSD DSP to do it digitally without conversion to PCM. Some SACD players have such a DSP system.

For my SACD listening, I turn off the bass management of my SACD player (A Sony, which uses a "1 bit" DSP to do bass management), and let the full-range signals play through all speakers. To make things difficult, I do not use a subwoofer, but instead have large towers up front, which handle all my bass needs. Luckily, my receiver mixes the sub input of the 5.1 & 7.1 inputs into the front channels (in the analog domain) when the subwoofer is set to off. I am basically counting on most of the bass being in the front and/or sub channels of the discs, since my smaller (but not tiny) center and surrounds can't reproduce really deep bass. So far I don't think that I am missing anything, based my comparisons of the 2-channel tracks to the same 5.1 channel tracks. Levels can be adjusted on the receiver, but time alignment is not available. That isn't an issue for me, as my speakers are all at equal distances from the sweet spot.

 

[Ron Newsome]

Let's not debate whether DSD (SACD) or PCM is better, but by putting your SACD audio through a receiver that converts it to PCM, you will get the worst of both worlds and the best of neither!

I totally disagree with that. Please explain in detail the damage that's supposedly done to the DSD signal when converted by a 96khz/24bit A/D converter. I've had my DVD player connected in this manner and I heard no differences, and I know my hearing is good! The only "bad" thing that happens is a lowered frequency responce out to 48khz. Can you hear out to 48khz? Have you actually heard a SACD connected in this manner or are you just repeating what you've been told by other misinformed people?

 

[David Judah]

Have you actually heard a SACD connected in this manner or are you just repeating what you've been told by other misinformed people?

Easy there, Tiger. He's not misinformed--what he wrote is what's happening. Now whether someone is able to detect the difference is another matter altogether. Some people like to have all their bases covered and some people don't even have that option for multi-channel playback.

DJ

 

[Tyler DJW]

I know you don't want the ICBM because of the time-alignment feature but, for me the time-alignment doesn't mean all that much. All of my speakers are withing 6 feet (relative) of my sweet spot and I honestly can't tell a difference with compensation on or off. However, the flexiblity of the ICBM is impossible to beat. For me, the tradeoff of losing my time alignment and gaining bass management flexibility was an easy one. It really depends on your room layout, but it's something to consider.

 

[Ron Newsome]

DJ said:

The extra generation of A/D-D/A conversion adds noise and introduces artifacts in the treble......

Yeah, like way up in the ultrasonic treble where you can't even hear it. So what's the big deal?


Okay! I see, so rather than go through a transparent conversion for proper bass management so one can hear the signal the way its supposed to be heard when using small speakers; you feel it's okay to tell un-informed people to send a full range signal to small speakers that can't possibly reproduce that signal just to avoid this so called "degrading conversion", thus forgoing proper bass management and losing alot of the bass itself.

Umm Hmm!

 

[Philip Hamm]

Wow, Ron, feeling confrontational today, huh?

I agree that converting DSD from SACD to PCM defeats the purpose of DSD. I also agree that almost nobody's going to hear the difference between converted and non-converted music. But just the possible problem is enough to make people nervous. I certainly wouldn't want to force all that conversion.

John,

You do not want to use an ICBM because it won't manage time delay.

Yet, no receiver or pre/pro that I know of can manage time delay for the 5.1 ins.

So your aversion to the ICBM doesn't make any sense.

The ICBM is the solution for you if you keep your receiver. What's your receiver now? Are you in upgrade mode? I think the only receiver that might serve your purpose (I believe you want high quality analog bass management on the 5.1 inputs, correct?) is the Rotel 1066. The Outlaw 950 does a fantastic job as well if you're willing to go the separates route.

 

[AaronBatiuk]

Ron said:

Okay! I see, so rather than go through a transparent conversion for proper bass management...

"transparent"? That's subjective at best.

DSD as implemented in SACD has certain limitations, including noise and reduced dynamic range at the extreme high end of the audible spectrum. PCM has certain limitations such as slower transient reponse and filtering issues. By converting a signal derived from SACD to PCM, you really do get the worst of both and the best of neither. That doesn't mean it sounds bad. It is just a fact.

 

[Ron Newsome]

Aaron said:

By converting a signal derived from SACD to PCM, you really do get the worst of both and the best of neither. That doesn't mean it sounds bad.

Oh I see, so I must have took that "worst of both and the best of neither" thing the wrong way!

As for all the other stuff you said, that's all fine and dandy, but can you hear all this nastiness you speak of that's caused by a simple conversion? Why are you unnecessarily scaring people by telling them that DSD->PCM is bad when you can't even hear the so called bad effects of this conversion?

 

[Ron Newsome]

Mr. Hamm said:

Yet, no receiver or pre/pro that I know of can manage time delay for the 5.1 ins.

Pioneer 49TX, Denon 5803, and Anthem AV-20 are the ones I know of, yet these are out John's price range.

 

[Philip Hamm]

Pioneer 49TX, Denon 5803, and Anthem AV-20 are the ones I know of, yet these are out John's price range.

Not in the analog domain either, which is preferred for reasons that you may not agree with, but many do.

 

[Juan M]

The H/K 525 does digital bass management on the multi-channel inputs. It is well in the price range.

 

[LanceJ]

Here's a link very closely related to this discussion:

http://www.smr-home-theatre.org/surr.../page_07.shtml

LJ