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Stereophile "confirms" Moncrieff's SACD comments ?

You folks remember a thread about SACD that mentioned J. Peter Moncrieff's comments about SACD being "junky" at higher frequencies ? Well, if you read the September issue of Stereophile's review of the $16,500 Accuphase SACD player, you will see that John Atkinson somewhat confirms Moncrieff's statements. Here is a direct excerpt from the test results that JA published in that specific Stereophile review ( pages 115-116 ):

"Again, the player's excellent dynamic range is revealed, at least in the low treble and below. Note, however, the rise in the noise floor above 2 KHz, this due to the aggressive noise-shaping used by the SACD's DSD encoding. By comparing fig 4 with fig 3, you can see that SACD has less inherit dynamic range above 10 KHz than CD, though this is largely academic, i feel."

Since you can't see the graphs without looking at the actual magazine, i'll try to sum it up. CD shows a rise in noise above appr 2 - 3 KHz. The slope climbs at a gradual rate as frequency rises. On the other hand, SACD shows the same rise in noise at about the same frequency point, but the slope is much faster and sharper. By the time we get to 20 KHz, standard "redbook" CD is actually about 15 db's quieter in terms of the noise floor and increased dynamic range.

Besides all of the above, which some "might" say justifies Moncrieff's opinions of poorer high frequency performance on SACD, JA goes on to show the spectral analysis well beyond the 20 KHz range. The rising noise level that begins at about 2 - 3 KHz continues to rise until we hit appr 70 KHz. Using a dithered 1 KHz tone as a reference, the noise level climbs to a point that is PHENOMENALLY high i.e. appr 80+ dB's noisier than it is at 1 KHz !!!

While i don't know if this phenomena is directly related to the Accuphase design being used or can be found in all SACD players due to the wave-shaping taking place, it makes me wonder if this is what has given me a headache aka "listening fatigue" on a few occasions when listening to some SACD's ??? Is it possible that the level of ultrasonic noise and ringing is high enough to the point that it can ruin what might otherwise be a pleasureable experience ?

As a side note, the jitter on this machine is PHENOMENALLY high. JA measures it at 4.26 nanoseconds of peak to peak jitter while running in redbook format. He comments that this is "more than 20 times higher than i have found in the best cd players and processors". He then goes on to "feed a signal into the DAC section of the player via the DP-85's S/PDIF data input with 16 bit data of the same signal, the measured jitter level dropped to a respectable 311 picoseconds." As such, the phenomenally high level of jitter is directly related to how they are transferring signal from the transport into the DAC. For a "lowly" $16.5K, you would think that they might be able to do a little better. Even the "respectable" 331 picoseconds of jitter is quite high in my opinion. Sean
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sean
djjd
61 posts
 
Sean, I haven't seen the article in question. Does JA give any explanation for why he thought the SACD's lower HF dynamic range was academic? If the noise is very low to begin with -- as it should be for a player of this caliber (also evident from JA's statement that the player's dynamic range is excellent) -- a 15 dB increase in the SACD noise floor at 20 kHz may not be problematic, much less audible. Again, I haven't seen the graph, but I wonder if this may be what he meant by "academic." What is the baseline noise floor (i.e., what level was the 15 dB increase measured from)? How much dynamic range do you think is needed at 20 kHz to ensure fidelity of a recording? Does the SACD's slightly compressed HF dynamic range approach or exceed your threshold of concern?

The 80 dB rise in the noise out to 70 kHz is of greater concern to me. But here too, if the baseline noise is very low to begin with, even such a large noise increase in the ultrasonic may not be problematic, particularly since most systems greatly attenuate signals above 25 kHz. Then again, in very extended systems, perhaps some of the SACD's ultrasonic noise could get through and be sensed by certain listeners. Do you know if anyone has tried to measure SACD UHF noise from the speakers?

Don't know the answers - just putting out some stream-of-consciousness ramblings to see if we can come to understand the curious and somewhat troubling results you've pointed out. I'd be interested to hear your thoughts, along with everyone else's. Don
bufus
149 posts
 
Regardless of the specifications, I found the Sony SCD-C555ES SACD player (< $600) sounded great to me, better with SACD than redbook, and better than my Rega Planet. Obviously, an analog setup is going to have poor specs in comparison to CD but that doesn't mean that CD will sound better (most of the responders on this thread prefering LP.) Also, keep in mind that DVD-Audio does not have the extreme rise in noise floor at high frequencies like SACD does. In my limited experiments, on a tight budget, it seems like SACD just sounds better than DVD-Audio. OK, sorry for aimless rambling.
tswhitsel
126 posts
 
I have never owned anything but redbook CDs and have stayed away from SACD because it is a limited and expensive format. Add to that the fact that its future, or any new digital format for that matter, is questionable. I held out a good 10 years after digital hit the market place and like many here feel analog is still the most musical, although there is no shortage of bad analog recordings. Like many here I too have owned a plethora of inexpensive and expensive CD players and DACs over the past 10 years or so including 2 Accuphase units. But the only unit I've found to come close to the sound of analog are Jerry Ozment's tube output designs. I currently own my second Audio Logic model 34 DAC having sold the first one to a friend. I tried several after that sale including an Accuphase DP-65, but nothing came close to the Audio Logic. I was happy when I found a great deal on the second one here on Audiogon. Frankly I'm surprised more here on Audiogon have not caught on to Ozment's designs (he designed some for Jadis, Altis, and VAC I believe). Perhaps Audio Logic is just not mainstream enough to have gotten the reviews that drive this silly hobby so much. It surprises me how close the model 34 comes to the sound of my Well Tempered Reference and with good recordings it can be quite stunning. I also use a CEC TL2 for a transport, which I have found to be the most analog sounding so far. For me it has always been about the music and for the moment it looks like redbook is here to stay, and the used market is flooded with redbook CDs, however good or bad they may be. Seems no one feels that SACD players sound as good on redbook CDs anyway. For now anyway I'll stick with my Audio Logic and would encourage others to check out Ozment's designs. Just my two cents worth in this never ending debate.
pardales
652 posts
 
After experimenting with SACD via a Sony 333 changer I have decided to maximize my extensive redbook collection. I have the new Mcintosh changer which sounds great and is utterly non-fatiguing, and I am going to audition an MSB Platinum Plus and a few other DAC's just to see if they make dramatic improvements. There are tons of redbook CD's out there and SACD just does not have enough titles I want at reasonable prices.

I can't speak to the numbers discussed earlier in the thread, but SACD is just nor practical for me. Good thread, thanks,
clueless
763 posts
 
Sean, maybe JA needs to upgrade his cables. I'd recommend the new the "Zeus Jitter-Litter 2002s” They use an advanced proprietary transmission-line method to redirect the incident and reflective waves caused by the jitter. It’s really straightforward. The wavelength of the JitterLitter mechanism is equal to the Square root of the frequency divided by the change in angular velocity divided by Pi:

λ= √f/∆ω /π

I’ve used this cable to keep my toaster from popping up prematurely for years.

Sincerely
I remain,
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