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
>

sean

Showing 2 responses by czbbcl

I agree that SACD is a superior format more information is more information and one step closer to pure analog. This is obviously an over simplified comment but true non the less. The decimation and interpolation filters used on many pure redbook players try to create something that is not there. I have heard most of the top gun redbook players the capitole included and while they are very good (IMO) SACD is still superior.

As far as price of the software it appears to be coming down as more labels and releases are created. You can now buy hybrids for around $17.00 and in some cases less. I guess I have strayed away from the original topic but.... my two cents worth. However, most important irrespective of which format you prefer (enjoy the music).
Let the music(data) be your guide not some preconceived notion of why something can't sound as good because of the manufacturer or looks or etc, etc. You have in fact determined the outcome(mentally) before the experiment has even begun.

There are a couple of threads here on AG ,maybe many, on the topic of hearing differences with various digital pieces and the impact(improvement) they make in these listeners systems. I have determine in my system the test players showed little improvement over my 10 year old philips cd80. With my electronics and speakers the SACD players playing SACD(various listeners over extended listening periods) were the winners more often than not with redbook being mixed.

However, keep in mind hearing recall is very subjective and in and of itselve unreliable.