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DVD-A vs. SACD

I'm afraid of getting a bunch of "We've already talked about this" rotten tomatoes thrown at me, but there isn't a search function here and I hate scrolling back through old pages.

I have read two slightly contradictory articles on the issue. The first one, here http://www.audiorevolution.com/equip/dvdavssacd/

says SACD is better but only under the circumstance that no DSP is done to the material after recording, which means almost never.
To fill in what he says with a few more facts. Originally DVD-A was going to be 3 channels 24/96 and 3 channels 16/48 in surround mode and 2 channels 24/192 in stereo. The sampling rate of stereo was set so high to keep the bit rate constant. Meridian Lossless Compression came in and made it so all 5 of the main channels could be recorded 24/96. He is right that 24/192 does not increase perceptual sound quality.

The other article
http://sound.westhost.com/cd-sacd-dvda.htm
is scathing towards SACD. But there are a few questions I have.
One, he talks as if the only kind of DACs on the market are bitstream and "multibit." If you look at Burr-brown's product sheets you will see 3 types: DSD (bitstream), delta-sigma (the most common type on middle and high end consumer products), and "advanced segment" which are right in the price range he talks about for "true multibit" DACs.
Similarly, I once read a passing comment on the laserdisc newsgroup that a tech was disappointed when he opened up a MLD-7020 and saw that McIntosh did not replace Pioneer's "bitstream" DACs with true audiophile DACs. Elsewhere I have learned that delta-sigma DACs typically have an internal resolution of 4 bits (from someone who had not studied conumer audio products in many years, however).

Thinking in terms of my own theory, if you take 24/96 and change it into 1 bit oversampled 24 times, I'm not quite sure why that wouldn't work. I see 2 problems. Problem 1 is that SACD is oversampled 29 and 5/30 times. I don't know a theoretical model where that gets you anywhere.

And, I can see how reconstructing a DSD waveform would produce more of a triangle wave rather than a sine wave, since you'd have a bunch of extra data points between the critical points. But I really don't know squat about the hardware implementation of DAC design, so I don't know if it really works like that. And my vision of filling in the gaps with extra data points only works for integer multiple oversampling, so there are some things I am not seeing.
128x128dnewhous

Showing 2 responses by tbg

tbg
5,263 posts
 
Thus far, I have always preferred SACD. I have one DVDA that sounds quite good but about 20 that do not. I have about 400 SACDs and in many cases have cd counterparts. I have so many SACDs as I seek all that are released that are within my tastes.

I said "thus far" as changes in mods of my Exemplar universal players have had differential impacts on the sounds of different formats.

I find SACDs give a much more realistic sound stage, especially in live performances. I must also say that redbook reproduction has greatly improved. XRCD24s in particular equal or exceed many of my SACDs.

I don't care if many say the newer formats are dead; I continue to buy many SACDs each month. I also find vinyl clearly superior but much less convenient.
tbg
5,263 posts
 
Donbellphd, I understand your logic. I have three thoughts. One your assumption may be incorrect about direct to digital. Two, even if true, the dac used may be superior to those in homes. Third, analog transfer even from digitally recorded records may be superior to dacs.

Even with top vinyl and digital sources, there is a less synthetic sound that you get with vinyl. I always know even apart from pops and clicks which is digital and which is vinyl. I want to prefer digital as it is easier to deal with.
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