Sony SCD-555ES Review (SACD & CD Player)

[Owl]

Thanks for spending the time experimenting and explaining the DSD process in greater detail. Sony all but stopped making single red book cd players at that time, and campaigned hard on super audio.

 

[NTTY]

You're welcome, especially as I owe you so much!

You're welcome and I'm thinking about a version 7.3 of the test CD with some of the tests you suggested and used for this review. And, influenced by @Vintage02, I'm thinking about a commercial copy from a glass master which would make it more widely accepted by CD/SACD/DVD players (some don't read a burnt CD).

To the best of my knowledge, I cannot perform the "max resolution" test with the System One software. The only method which would resembles your test would be to add a sharp analogue band-limiting filter @ 6 kHz in the analogue analyzer signal path before the distortion residual is measured by the reading meter. That may be done.

Yes, that would probably work.

For all test, I let the System One in "Auto ranging". I try to range the input manually on few tests. Sometimes I got better figures, sometimes not.

Ah ok, it has an auto-ranger, which explains the good reading of the 3DC. Nice.

 

[Scytales]

You're welcome and I'm thinking about a version 7.3 of the test CD with some of the tests you suggested and used for this review. And, influenced by @Vintage02, I'm thinking about a commercial copy from a glass master which would make it more widely accepted by CD/SACD/DVD players (some don't read a burnt CD).

That would be awesome!

I cannot but resist to take the opportunity to publicly out-loud the dream I have speak about to you privately: the realization of not only a test CD, but a hybrid test CD/SACD with the help of @pkane's Multitone software for the DSD part.

I am confident Polyhymnia or Super Audio Mastering in Europe, or Bolo Digital or 5/4 Productions in the States, or other third parties, would be able to produce the digital master for the SACD layer.

I am in the belief that a new proper SACD test disc could interest many engineers, hi-fi brands, journalists, reviewers, researchers or hobbyists (notably in the ASR community) around the world because the only two test SACDs ever made have been out of print for decades.

Ah ok, it has an auto-ranger, which explains the good reading of the 3DC. Nice.

When there is no disc in the tray, the SCD-555ES outputs are muted by relays. In that case, the inputs of the Audio Precision are short-circuited to ground at the player's side through 62 ohms output resistors on the Sony outputs. In this situation, the AP auto-ranges on its highest sensitive setting and measures about 0.9 µV RMS (unweighted) of noise in a 22 Hz to 20 kHz bandwidth.

 

[WilliamfromParis]

That would be awesome!

I cannot but resist to take the opportunity to publicly out-loud the dream I have speak about to you privately: the realization of not only a test CD, but a hybrid test CD/SACD with the help of @pkane's Multitone software for the DSD part.

I am confident Polyhymnia or Super Audio Mastering in Europe, or Bolo Digital or 5/4 Productions in the States, or other third parties, would be able to produce the digital master for the SACD layer.

I am in the belief that a new proper SACD test disc could interest many engineers, hi-fi brands, journalists, reviewers, researchers or hobbyists (notably in the ASR community) around the world because the only two test SACDs ever made have been out of print for decades.



When there is no disc in the tray, the SCD-555ES outputs are muted by relays. In that case, the inputs of the Audio Precision are short-circuited to ground at the player's side through 62 ohms output resistors on the Sony outputs. In this situation, the AP auto-ranges on its highest sensitive setting and measures about 0.9 µV RMS (unweighed) of noise in a 22 Hz to 20 kHz bandwidth.

Guys, you are creasy but I like that so much.

 

[AnalogSteph]

I would consider the following steps important before a venture like that could go ahead:
1. Make the tracklist 100% airtight first, so that absolutely everything one could possibly want on a test CD is on there. Even a -90.31 dBFS undithered and a fullscale square wave (maybe 1 min + another 1 min at 6 dB lower).

2. Research economics of making what is invariably going to be a small run of either CDs or hybrid SACDs. Stampers have a certain lifetime, which according to Google is about 10,000 discs and 3-7 years. I would expect initial tooling cost to be substantial, while material cost per unit is likely to be low, so at the kind of run sizes we are likely to be looking at (maybe a few hundred), making some extra discs is going to be almost free up to the stamper lifetime limit. I might target a run of maybe 500 and see what unit cost comes out as.

Don't forget the cost of creating disc and album artwork and printing. A basic 1980s looks seems appropriate for the disc anyway, the back and cover don't really need to be a whole lot more fancy.

If you don't fancy storing hundreds of finished CDs in jewelcases, I would inquire about delivery on spindles or the like. Assembling a few dozen cases by hand as orders come in seems manageable enough.

I would expect making hybrid SACDs to be more expensive at all stages for a number of obvious reasons.

 

[Deleted member 89070]

Thanks for the review and all the work on it. My trusted Sony feels a lot better now

View attachment 497944

that rack looks nice too. Brand/make? I'm just wondering

 

[BeeKay]

that rack looks nice too. Brand/make? I'm just wondering

That’s by ‚solidsteel‘. But quite an older, discontinued series.

 

[Haskil]

Guys, you are creasy but I like that so much.

As we say in France: they were rocked too close to the wall when they were babies.

 

[Vintage02]

That would be awesome!

I cannot but resist to take the opportunity to publicly out-loud the dream I have speak about to you privately: the realization of not only a test CD, but a hybrid test CD/SACD with the help of @pkane's Multitone software for the DSD part.

I am confident Polyhymnia or Super Audio Mastering in Europe, or Bolo Digital or 5/4 Productions in the States, or other third parties, would be able to produce the digital master for the SACD layer.

I am in the belief that a new proper SACD test disc could interest many engineers, hi-fi brands, journalists, reviewers, researchers or hobbyists (notably in the ASR community) around the world because the only two test SACDs ever made have been out of print for decades.



When there is no disc in the tray, the SCD-555ES outputs are muted by relays. In that case, the inputs of the Audio Precision are short-circuited to ground at the player's side through 62 ohms output resistors on the Sony outputs. In this situation, the AP auto-ranges on its highest sensitive setting and measures about 0.9 µV RMS (unweighted) of noise in a 22 Hz to 20 kHz bandwidth.

Good evening,

Regarding the production of a test CD that is pressed and not burned, there is no problem at all. Doing this on a SACD is an almost impossible task because there are practically no industrial SACD production lines left and the standard requires an expensive license. The few companies you mentioned reserve their production capabilities for projects that are much more profitable than a test SACD. Let's not forget that even though the SACD on paper was technically a success, the CD format lock-in caused its downfall. We will have to be content with a test CD that will be made according to the rules to be recognized by all players; at least that is the goal of this project. It will then be available for those who feel they need it to test their CD players.

 

[Sale64]

Great rewiev. Do you have any experience with changing laser in this player? I have mine boxed since reading problems started and replaced with Denon Scd3000n. Bought new laser from China, but heard the change succes is not garanted, because some fine tuning with dedicated sony disk is needed.

 

[Scytales]

Great rewiev. Do you have any experience with changing laser in this player? I have mine boxed since reading problems started and replaced with Denon Scd3000n. Bought new laser from China, but heard the change succes is not garanted, because some fine tuning with dedicated sony disk is needed.

The service manual of the Sony SCD-555ES states that the player servo-board performs auto adjustments after any replacement of parts, but a check of performance is recommended. It is that checking procedure that mandates the use of specific test CD and SACD from Sony: the YEDS-18 or PATD-012 (CD) and the SATD-S4 (single layer SACD).

So, it is possible to try to replace a laser optical pick-up with a new one. However, without these test discs, it is impossible to perform the necessary measurements to verify that the device is functioning according to specifications.

 

[Duck-Twacy]

I have one, not sure how long. Must be about 25 years now. Bought it for 700 euro's new on a German web site. I had it modified with a better (Tent) clock and a diferent output stage (Zapfilter from LCAudio, also has balanced output). Never mist a beat

 

[Scytales]

Numerous modifications have been proposed for this player (and many other Sony player models) by third parties, but no one has ever documented the improvements brought about by these modifications using rigorous before/after measurements.

Therefore, if you are willing to take the risk of sending your player to me or to @NTTY, I would be very interested in measuring it!

 

[Duck-Twacy]

Can't send my precious I am afraid... But if you are interested in that output stage, here some info (company doesnt exist anymore btw) https://www.diyaudio.com/community/threads/lcaudio-zapfilter.944/ or http://www.octave-electronics.com/lcaudio/zapfilter.shtml

 

[AdrianusG]

(Continuation from message #1)

5. Special Tests

Here is a capture of the waveform of a 997 Hz sine at -90.31 dBFS without dither from NTTY Test CD:

View attachment 502991

The waveform is a bit noisy, but the three discrete voltage steps are clearly visible.

The Sony DAC is perfectly monotonic, i.e. increasing digital codes produce consistently increasing analogue outputs at the lowest levels. Most probably this characteristic is no longer difficult to get nowadays, but at least it let us see a pretty picture:

View attachment 498030

Non-monotonic DAC can also be revealed by another special test which was proposed by Audio Precision in 1991 to check the absence of modulation of the noise floor of D/A converters at different levels (Richard C. Cabot, Noise Modulation in Digital Audio Equipment, AES preprint 3021). This test consists of accumulating on the same graph a third octave analysis of the quantization noise after the removal of a low frequency test signal at different levels from -50 to -100 dBFS. Any change on the shape of the noise floor would signal a modulation of this noise in function of level. Audio Precision quoted experiments previously conducted at Dolby Laboratories that had shown that noise modulation of as little as 2 dB may be audible. Nowadays, this test may have no longer relevance with modern D/A converters, especially sigma-delta converters, but maybe it can still be useful to check ladder type converters. In any case, here is this test performed on the Sony SCD-555ES as proposed by Audio Precision:

View attachment 497356

The noise floors at different levels overlap almost perfectly, save for small "blips" that look like there are not significant. It is enlightening to compared this graph with the noise in the audio band between 500 Hz to 20 kHz obtained with the same 3rd octave band pass filter when the DAC is fed with an "Infinity Zero" signal (see Part II, 2 above). The elevated noise that can be shown on the graph above compared to the graph in Part II, 2 is due to the fact that the noise coming from the digital processing adds to the noise of the analogue circuit of the player.

The noise modulation test can be performed in a more modern way by accumulating FFT spectra of the different test signal levels:

View attachment 497357

The noise generated by the different test signals overlap perfectly, confirming the absence of any noise modulation.

Finally, I used special dithered signals made by NTTY on the model of the Pierre Vérany Digital Test CD, which contains unique (non-dithered) tracks to perform a peculiar test called "intermodulation by crosstalk". The theory of operation of this test is as follows: the channel under test plays a 5 kHz tone and the other channel simultaneously plays a 1 kHz tone, both at 0 dBFS. If there is a significant crosstalk between channels, the 1 kHz tone can theoretically intermodulate with the 5 kHz tone to produce on the channel under test a difference frequency of 4 kHz and/or side-bands at 4 and 6 kHz due to amplitude modulation of the 5 kHz tone by the 1 kHz crosstalk tone. This test has been designed at a time when most CD players have only a single digital to analogue converter for two channels for cost-savings reason. These CD players had to demultiplexe the left channel from the right by routing the output of the single DAC alternatively to each one of the two channels at twice the CD sampling frequency.

I looked for the intermodulation product after I had the Audio Precision notched out the 5 kHz tone to increase resolution. I found nothing in the right to left direction, but in the left to right, I have found small 4 kHz and 6 kHz side-bands at about -120 dBr (after the attenuation of the notch filter has been compensated for):

View attachment 497526

The relevance of this measurement as an intermodulation distortion assessment is debatable, but a case can perhaps be made that it is in some way a more stringent crosstalk test than the one I performed and have shown the result above. In an usual crosstalk measurement, one channel only plays back some signal whereas the analyzed channel remains silent. In this case, many D/A converters may mute the channel under scrutiny. When the test signals designed for the Pierre Verany Digital Test CD are played back, on the contrary, both channels are very well alive because they have both a tone at maximum level to reproduce.


6. Disc Readability

To end the first part of this review dedicated to CD replay, I have used the famous Pierre Vérany Digital Test CD2 to check the ability of the Sony SCD-555ES to play damaged discs or disc pressings that are not compliant to the Red Book (RB) specifications. The criteria of failure on a test is either glitches, warping of the output waveform or an increase of THD+N from the nominal value. The last one is the most stringent: if it were relaxed, the player would have passed more test steps for it actually proceeds to produce a stable output with only moderate increase of THD+N on some tracks. As NTTY obviously uses the same disc to perform its own tests, I will borrow his table:

Test Type	Variable parameter(s)	Results
Variation of linear cutting velocity	1.4 then 1.2 to 1.4 m/s in 0.05 m/s steps	All tests passed
Combined variations of track pitch and velocity	From 1.2 m/s to 1.40 m/s combined with 1.5 µm & 1.7 µm pitch	All tests passed
Variation of track pitch	1.5 µm to 1.7 µm in 0.05 µm steps	All tests passed
HF detection level	Variation of the pits/lands ratio from +2 to +18%	All tests passed
Drop-outs tests	0.05 to 0.2 mm (RB spec.) and 0.3 to 4 mm (non-spec.)	All RB spec. tests passed - Pass to 1.25 mm Fails from 1.5 mm
Combined drop-out size variation & minimum track pitch	1.5 µm + 1 to 2.4 mm	Pass to 1 mm Fails from 1.5 mm
Successive drop-outs	2x0.1 mm to 2x3 mm	Pass to 2x1 mm Fails from 2x1.5 mm

Part III: Measurements of the Sony SCD-555ES as an SACD Player

Measuring an SACD disc player presents two challenges.

The first is the lack of availability of proper test disc. Only two test SACDs designed to assess performance of disc players have ever been made by Sony and Philips and they have been out of print for a very long time. The only available SACDs with some more or less useful test signals that are procurable are designed to set up stereo or multichannel Hi-Fi systems, not to measure the performance of the DACs of disc players. Nevertheless, I will try to make good use of the test SACDs that are available.

The second is the high level of out-of-band noise generated by the sigma-delta modulation. This out of band noise may upset wide-band analogue audio analyzer. The Audio Precision System One does not escape this problem. Thus, the measurements I am able to perform are limited for now, but I will proceed to work on the challenge.

For this part, I can use only one test disc that has been designed mostly to set up multichannel audio systems but that also gets some stereo test tracks : the Denon Audio Check SACD.


1. Frequency response

The Denon SACD has no 1 kHz or so sine tone at the nominal 0 dB SACD level, but it gets several sine signals at -16 dB SACD that are precisely aligned with the level of PCM sine signals at -16 dBFS. It is thus possible to calculate the nominal output level of the Sony by measuring the signals at -16 dB SACD and adding 16 dB to the measured level. The output is exactly the same (2.15 V RMS) as with corresponding PCM sine signals and the channel matching is identical.

That means that the SCD-555ES is a perfect candidate to compare CDs and SACDs at matched levels if you are able to find music program materials that are mastered identically in both formats.

Due to the lack of 1 kHz sine at full 0 dB SACD level, I cannot show a "dashboard". All I can report is measurements made elsewhere by a third party with an Audio Precision System Two and a proper SACD test disc that has revealed a very low harmonic distortion of (worst case) -115.4 dB (0.00017%), only made of the second and the third harmonics.

The frequency response has been checked with a glide tone signal from 5 Hz to 30 kHz at -20 dB SACD from the Denon disc:

View attachment 497361

You can see that the response is tailored exactly the same way as with CD replay (beware of the different horizontal scale on the above graph when comparing!). This confirms the fact that the frequency response is imposed by the player's analogue output low-pass filter. Again, this made the SCD-555ES a perfect player to compare CD and SACD editions of the same program material contrary, for example, to the Pioneer DV-868AVi, which has both different output levels and frequency response between PCM mode and SACD mode.

It is possible to explore the response of the SCD-555ES much higher in frequency with the pink noise tracks of the Denon SACD. It is well known that a 1/3 octave analysis of pink noise should show a flat response. Let’s check that with the Audio Precision analogue band-pass filter:

View attachment 497362

Now that is interesting. The usable frequency response extends to somewhat 55 kHz with a gentle roll-off. From 55 kHz, the response flattens a bit: this is where the noise is no longer pink in nature: it is the shaped quantization noise typical of DSD that overcomes the pink noise. But the noise level quickly goes down following a regular slope. Compared to the Pioneer DV-868AVi I already reviewed, the Sony SCD-555ES has much more effective combined digital and analogue low-pass filters. In fact, I have measured more than 4 times less noise above 100 kHz with the Sony than with the Pioneer. The performance of the Sony is by design: its active analogue low-pass filter is one of the most potent I know of among disc players. It would be interesting to compare this performance with devices using modern D/A converters which rely more on digital low-pass filter and less on analogue filters for DSD replay.

Another way to view the pink noise, though in a more restricted bandwidth, is to make an FFT at the maximum sampling frequency the Audio Precision System One is capable of. Moreover, as the Denon Audio Check SACD pink noise tracks get signal on one channel only at a time, we are going to see what is actually on the muted channel:

View attachment 497363

As you can see, the pink noise effectively extends to 60 kHz before it is overcame by the shaped quantization noise. The most interesting thing is that the quantization noise is also visible on the muted channel (the fact that the HF noise of both channel doesn't overlap seems to be due to the Denon test disc). That means that the silence is actually an analogue mute signal and that the DAC of the player stays alive, as what happens with an "Infinity Zero" signal. This gives the opportunity to measure the true signal to noise ratio of the player thanks to this DSD analogue mute signal.

2. Noise measurements

To compute the signal to noise ratio, one must measure the noise floor in the audio band when playing an analogue mute track and refer the result to 0 dB SACD. Bear in mind though, that 0 dB SACD is not the maximum signal level that SACD is capable of: as I have explained on another thread, the SACD audio specification allows short term peak excursions at +3.1 dB SACD.

Unfortunately, I encountered a strange behavior that makes me doubt the reliability of the System One analogue analyzer to measure audio band noise level of DSD signals. So, instead, we can have a look at the noise floor in the audio band with an FFT analysis, which works fine:

View attachment 497365

Compared to a similar measurement in the same bandwidth with a PCM "Infinity Zero" signal (not shown), we get a somewhat similar noise floor, except for a bit more low frequency mains interference and the small blips around 550 and 1,200 Hz in case of SACD replay. So, we can assume that, when DSD data is replayed, the SCD-555ES is capable of more or less the full signal to noise ratio measured with an "Infinity Zero" PCM signal, whereas of course the true SNR from CD data would be limited by the added quantization noise in the presence of any signals.

This ends the measurements I am able to perform in DSD for now.

I just want to add that this Sony SCD-555ES has been my main CD and SACD players for 20 years and still is. I have never found a flaw in the sound.

I hope you find this review interesting.

Hi,

In Japan at the end of the day before leaving, they always say
大変な作業、ありがとうございました。
Taihen'na sagyō, arigatōgozaimashita.
"Thank you for your hard work."

What a great review

 

[SigmaR1]

The most interesting filter is number 3. Yes it attenuates more than the standard one at the top of the audio band, but its remains relatively sharp indeed and have a lower out of band noise floor. Sony says this is a single stage FIR filter.

I just realised that the 4th filter, isn’t so bad since it’s quite sharp and the out of band noise floor is équivalent to the performance of the cdp x559es, and better than the cdp X333es!