Axiom Home Page Forums General Discussion Home Theater Will there be any 7.1 true hd or DDhd hd dvd's

Great analogy, Michael. I feel exactly the same. Well said!

JH, in addition to the points Alan made, keep in mind that even present 5.1 DVDs can usefully be played on a 7.1 speaker setup. Applying DPLIIx or Logic 7 to the surround channels in 5.1(the front three channels aren't affected)extracts material which should be imaged in the back and steers it as stereo material to the back speakers.

>>I'm baffled as to why SACD and DVDA's have not gained more popularity.

Because so many of us are too lazy to hook up the extra connections or fiddle with the player to output SACD over the stereo connection rather than the compatibility tracks. We listen to the CD-compatible tracks and say "sure, it sounds a bit better, but not profoundly better"

At least that's my excuse.

So, Johns the guy thats been holding up the advancement of SACD/DVDA

Hey Ajax,

You're comparing apples to oranges. Of course any multi-channel four-, five, or six-channel recording of music, be it DVD-Audio, SACD, Dolby Digital 5.1, DPLII(x), dts, or Logic7 will, in most cases, sound much more realistic than 2-channel stereo (see my article on the inherent limitations of 2-channel stereo in the Axiom newsletter archives)
http://www.axiomaudio.com/stereoflaw.html

The real test is a careful comparison between a discreet multichannel format like Dolby Digital 5.1 and DVD-Audio/SACD, using the same music. When the channel levels are identical, and the same mix is used, the audible improvements are very subtle, in many instances inaudible.

The reasons for the commercial failure of DVD-A and SACD are many and complex, not the least of which is their incompatibility with most DVD players.

Hi Alan,

Just my opinion, but I think the apples to oranges comparison is the correct one. My comments about my demo were in response to a comment that “it's clear that the slight audible improvements offered by [SACD and DVD-A] were not sufficient to persuade consumers to adopt them [in preference to the 2 channel CD].” The point I was trying to make with my demo is that SACD and DVD-A do "sound much more realistic" than a standard CD, hence, my chagrin at the lack of success of the multichannel formats.

However, I did say that my demo included comparing PLII to SACD. And the gasps I elicited occurred when I changed from PLII to SACD using the same music from the same disc. I will admit that the volumes were probably not quite identical, but close. I’m willing to consider that the volume difference and/or the placebo affect may have something to do with the difference I hear, but, at this point, I remain skeptical that those factors explain all the difference.

I'm getting way past my level of expertise, but isn't there a bit rate difference, or some recording quality difference, between a redbook 2 channel CD, and a(n) SACD/DVD-A which would provide an improvement in sound quality, regardless of the number of channels? Does a 2 channel SACD offer improvement over a 2 channel redbook SACD? Would laying PLII(x)over the redbook CD compensate for that difference and make it equal in quality to a 2 channel SACD?

I agree completely that DD 5.1, DTS, are as big an improvement over stereo as SACD and DVD-A.

DISCLAIMER: I mean no disrespect to those who are dedicated 2 channel fans. I firmly believe that people should listen to music the way that gives them the most pleasure.

I am a HD DVD owner and I can tell you that you can have 5.1 truehd now and it is better than DD or DTS.I just watched Batman Begins and my jaw is still on the floor.7.1 will come to HD DVD at some point just dont know when.The only problem is it will have to be thru HDMI as there is no 7.1 analog outputs on the toshiba.The guy who said that bluray has the bd50 it is still to early to count on bluray to do anything because they dont even have a player that works right yet.

oh and truehd is lossless

Jack, on the part of your reply where you ask about possible bit rate(sampling rate is also another difference)differences making a difference in sound quality even where multi-channel isn't a factor, yes that's often claimed. This hasn't come up much recently and one of my replies from three years ago still has some active links to good info. The poster "soundhound"(shown in his replies by his later boardname of "HAL 9000")explained how better recording, mixing and mastering made the difference that was often heard, not higher sampling and bit rates. He also pointed out that even on the same disc different mastering was often applied to CD and SACD layers, which could account for a difference.

When Sony and Philips were co-developing the CD format around 1980 they agreed to use a 44.1KHz sampling rate and 16 bits(Philips originally proposed that 14 bits were enough)as being more than sufficient for the frequency range of human ears and the dynamic range of the material that would be recorded. Since two digital samples exactly reproduce an analog waveform, 44.1KHz sampling exactly reproduces frequencies up to 22,050Hz, beyond audibility. Likewise, 16 bits provide for a theoretical maximum dynamic range of about 98dB(6.02n + 1.76dB), and actual recordings have at most 80dB of range(many almost uniformly loud pop recordings have a dynamic range on the order of 10dB).

So, while DVD-As/SACDs can sometimes sound better than CDs of the same performance, higher sampling and/or bits is unlikely to be a significant factor. Of course when the DVD-A/SACD has discrete multi-channel placement of performers in surround channels, this sounds different and hopefully better. On the other hand, where the surround channels contain only ambience information(most classical DVD-As/SACDs)rather than discrete performers, applying processing such as DPLII, Logic 7, Neo:6, etc. to CDs can provide a very similar result. I own one SACD and likely won't be getting any more.