If DVD-A is so good....

[Krink]

If DVD-A is so good.... why are manufactures scrambling for better bass management in their machines. Upto this point bass has absolutely sucked in DVD-A format. But not in SACD. The DVD-A machine companies are already touting better bass with the new machines. Why wasn't it on the original machines. Is it coloration in the sound. Sounds like I'm not gonna be listening to the real recording, but more of a synthisized version for DVD-A. It's nice to know that when I put on my vinyl...the sound is as close as I can get to the original recording.

[Uncle Al]

Bass management is a leftover from DVD-V, and one that should have been left there. In order to make explosions more explosive, earthquakes more quakey and roaring fires (or engines) more "roarey" (?- -u know what I mean), the motion picture industry - and hence, the home theater industry, opted for a DISCREET (emphasis intentional) subwoofer channel. As this was strictly an "effects" channel - it was suited to the material.

DVD-A (and DTS surround) is trying to make that setup suitable for music - but there are problems....

If you utilize a subwoofer in a music system, chances are you have carefully tweaked - either by calibration, or critical listening - the crossover setting suited to your system. After all - the subwoofer in a music system is dependant on the frequency response of your main speakers. If they deliver accurate response down to to 100 hz - you set your crossovers accordingly. If you purchae new speakers that are accurate down to 60 hz - you change the settings. You want to avoid a "hole" in your frequency response - and you want to maximize the potential of your main speakers.

A DISCREET subwoofer channel assumes that your mains are accurate to the frequency assigned to the subwoofer. It almost guarantees a slip in the frequency, somewhere. After all, we all have different equipment and environments. This is less noticable/important to a motion picture - but more critical in music. To make matters worse - the subwoofer channel is NOT part of the stereo fold down specifications on DVD-V. This is not always a factor, since many DVD's are authored with full frequency response in all of the speakers, but on certain titles, the 5.1 "fold down" track may sound thinner.

I think that for ALL home purposes - the subwoofer channel should be dictated by adjustible crossovers. There is no (or very little) directionality to deep bass frequencies. The need for a discreet channel is nebulous. However - the creators of DVD-A have adopted the discreet sub channel with all of it's faults. I guess the SACD specifications are more friendly, to those with or without subwoofers.

[Steve Hoffman]

Very good explaining, Uncle Al!

This is indeed quite a problem. I call this one of those "Phil Spector Nightmare" problems that the industry has to deal with; and FAST!

[GregM]

Indeed. The bass management crowd seem to be deluding themselves by putting their faith so totally in this digital manipulation. In addition to inducing phase shifts in the crossovers, bass management combines all discreet low frequency singals into one channel. Anytime you combine discreet signals, there will be natural cancellations, attenuations and accentuations, creating a new set of music singals which the recording engineer never intended. In other words, bass management not only screws up what is recorded, but can also create its own brand of "music".

If content developers want us to hear deep bass, they will not assign it to the rear channels, or even the center. After all, there aren't any bomb blasts going off behind us, like in Saving Private Ryan. There is simply no reason to put deep bass back there for music--and it can be argued that with the possible exception of ambient sounds and crowd noises, there is no reason to put any sounds back there.

[luke j. chung]

I'm one of the lucky ones who are able to get around the bass management problem by using full-range floor-standing towers for the front and surround corners and a full-range 3-way bookshelf speaker for my front center channel. All five of these speakers go down to at least the low 30s, the towers to the low 20s for bass. But you're right, this is a situation that needs prompt addressing by the audio manufacturers!:eek:

[MikeT]

Originally posted by Uncle Al
However - the creators of DVD-A have adopted the discreet sub channel with all of it's faults. I guess the SACD specifications are more friendly, to those with or without subwoofers.

Yes, but most of the new MCH SACDs released by Sony use the sub channel exactly the same way as DVD-Audio.

I agree, even though I am a supporter of surround sound music, that the sub channel probably doesn't need to be used with regard to music. Many DVD-A discs and MCH SACD disc - overuse the LFE channel so that at times the bass in out of proportion with the rest of the music. I have my sub dialed in correctly for movies, and every DVD-A or MCH SACD usually sends me to the subwoofer for adjustments. I really hate that.

[Gary]

Are the two channel SACD discs fold downs too? :eek:

[jkerr]

Originally posted by Gary
Are the two channel SACD discs fold downs too? :eek:

Do you mean 2 channel downmixed from multichannel? No. All SACDs have a dedicated 2 channel mix. If its a multichannel release, there's a sperate 2 channel mix on the disc.

What's really confusing is how dvd-a can have so many different combinations. Each dvd-a release may or may not have a dedicated 2 channel mix. Its very inconsistent.

[Grant]

Uncle Al,s explaination is one of the reasons I do not support DVD-A.

[GregM]

Originally posted by jkerr:
>> What's really confusing is how dvd-a can have so many different combinations. Each dvd-a release may or may not have a dedicated 2 channel mix. Its very inconsistent. <<

Yes, and so is the actual resolution/sampling rate of the music. DVD-A supports all manner of PCM from 16-bit to 24-bit at all flavors of sampling. It is creating more than a little confusion and anger. Part of the problem is that there simply isn't enough physical space on the disc for 24/192 surround mixes and separate stereo content, as implemented.

But for me the greatest travesty of DVD-A is the watermarking issue. You know, record labels have to pay a licensing fee for the watermark whether or not they choose to use it! :confused:

[rodney sherman]

I feel the same way when it comes to the mastering of dvd audio. Take a listen to Deep purple's Machine head and Foriegners self title dvd audio releases in 5.1 surround.The only bass that comes out of the bass channel is the bass guitar.I do like Fleetwood mac's roumors and Stone temple pilot's core(all of the bass from the drums and bass guitar is there).The format is still new and it will take time to do it right.Im happy that better sounding music media is hitting the market.I will support both dvd-a and sacd.Im very excited to be able to hear the eagles on dvd audio.I got to pick it up.;)

[jkerr]

Rodney, please turn off your caps lock when typing your postings. Its easier to read THAN SOMETHING IN ALL CAPS. It's llike SHOUTING!

thanks!