Hello everyone,
This is a review and measurements of the Sony BDP-S1700/K Blu-Ray/DVD/CD transport.
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Sony BDP-S1700/K - Presentation
A number of you have expressed their interest for recent Sony Blu-Ray transports, to know if they could act as decent CD Player. Two weeks ago, I was at the shopping center and saw that one at a very reasonable price (below $100) and so I went for it.
You can find all details about this device on
Sony's website, and the elements of interests for me, that I took from the community, were:
- This is a (CD) transport
- It has a Coax (SPDIF) output to use with modern or older DACs in a "standard" HiFi environment
- It is reasonably priced
I will be testing it on CD Transport perspective, and I will also have a quick look at higher resolution sources. The principle is to use Coax output only because I'm not equipped to measure digital HDMI output. I would probably need to invest into an AV preamplifier with HDMI input, but that's not planned.
So, it is a transport, no DAC inside, meaning that the back is very simple:
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We have one HDMI output and one Coax. It is not documented in the User Guide, but because SPDIF is not HDCP (Digital Content Protection) compliant, copyright holders do not allow high-quality, high-resolution audio to be passed through it. That means this Coax (SPDIF) output should be restricted to "CD quality", and that is max 16bits/48kHz. We'll check if that's the case, and since it implies an ASRC is in the digital chain, we want to know what's the impact of that on the PCM data (especially from CDA). In other words, and that's the main concern, can we get "digitally perfect" output from an Audio CD.
User Experience
No display on the front, you'll need a TV to see anything. Only two buttons, one to power on/off and one to open/close the tray, rest requires the remote control.
The good news is that, out of the box, there's no need to configure anything to listen to a CD. Plug in, insert the disc, press play on the remote (CD playback is selected by default after it recognizes there's a CD in the drawer), and you're good to go. Not even needed to connect it to a TV for whatever setup, provided you only intend to listen to a CDA.
It's not fast to skip a track, less so multiple, but is that a real problem if you're into listening to a full album at once? FFW/REW are available from the remote control but painful as it will skip 20sec at once and you get no audible feedback. But well, I survived it.
The drive is relatively noisy (50cm next to me), especially when reaching the outer section of a CD. It is difficult for me to tell you if you'd be annoyed as we don't have the same sensitivity to that type of noise. I could not hear it with my Beyer DT770Pro on my ears.
It had no issue reading 70min+ discs, CDR nor the CD layer of an SACD. I dreamt it would read the SACD layer and propose a downmix to PCM, but no. Anyways, most of the studios are now producing and releasing a CD layer made from the same mix than the one of the SACD master, so the quality is the same, only bit depth is decreased and proper shape dither applied to compensate for it, so I'm not too worried. A "stupid conversion to PCM" in the Player could be much worse.
Last before I go into the measurements blah blah, is that I must admit I spent unusual time listening to it (via the Topping D50III and A50III with my good old Beyer DT770 Pro), pushing the volume always more and more. I surprised myself, as I typed this review, to stop sometimes, close my eyes and listen to what I hear, or play air piano/drums/guitar. It made this review particularly long to finalize
That is, I had surprising pleasure and I guess it already tells you about what I'll soon report on quality perspective. The foot print of all my messy setup is reasonable as per the below picture (on top of Sir
Accuphase DP-70):
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You can't trust my old ears, anyways, but we are talking about a Sony, the masters of CD, and if Sony decides a device is to play a CD, it will play it per the Redbook. So yes, I am happy to report
it is gapless playback and
applies de-emphasis when required (in digital domain).
This is a proper CD player! In a world of where many actors have forgotten about the Redbook, or just don't care, this is reassuring. Thank you Sony!
I'll be dividing this review in 3 sections:
- CD digital measurements + Drive tests
- High-res digital audio measurements (from USB and DVD-A)
- Analogue measurements from the Topping DAC (CD source only)
Sony BDP-S1700/K - Measurements (Coax out, CDA as source)
All measurements performed with an E1DA Cosmos ADCiso (grade 0), and the Cosmos Scaler (100kohms from unbalanced input) for analog outputs, and a Motu UltraLite Mk5 for digital.
I am now consistent with my specific measurements for CD Players, as I described them in the post “
More than we hear”, and as I reported them for the
SMSL PL-200 review. I used the commercial version of my
Audio Technical CD for all measurements. Over time, this will help comparing the devices I reviewed.
The Sony BDP-1700S/K came with Firmware version M47.R.0011. I could not find a more recent one on Sony's website.
As a transport I only have the digital output to measure to verify it is "bit perfect". They are the same tests that I perform with all the CD Players I review when they offer a digital output.
This is my standard 999.91Hz test tone @0dBFS (without dither):
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It is the same as if I run this test directly from the original WAV file that was used to create the CD. So it is "perfect".
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Same with the good old 3DC test from Stereophile (undithered 997Hz sine at -90.31dBFS. With 16bits, the signal should appear (on a scope) as the 3DC levels of the smallest symmetrical sign magnitude digital signal):,
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It is the expected square view that we want to see, with the
Gibbs Phenomenon showing itself. That means no modification of the digital signal.
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Of course, jitter is absent:
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This the exact graphical representation of the test.
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In the end, my ultimate proof of "perfect" digital output is when I reuse the intersample overs test at 5512.50Hz, with a phase shift of 67.5°, like I did for the TASCAM CD-200 review. This signal generates an overshoot of +0.69dB and so if the signal would be modified before being sent, it would show either a reduction of amplitude or we'd see some sort of saturation/increase noise/distortion. So here we go:
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No changes when compared with the WAV file, again. We get the expected +0.69dB overshoot and no distortion whatsoever. So if there's an ASRC on the digital path (and there is one, see below), it works here in bypass mode.
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The only small issue I could find with he Sony is a small imprecision of the internal clock that travels through the SPDIF. If you use a converter that has a very low phase noise clock, this variation will be filtered out by the PLL. If not, then you'll get a reasonably low -25ppm deviation (good luck to hear that).
I won't be adding more unnecessary measurements, it is every time the same story: I get the same as the original WAV files.
It means the coax digital output of this transport is unaltered from CDA.
Sony BDP-1700S/K - Testing the drive
What would be good measurements if the drive would not properly read a slightly scratched CD, or one that was created at the limits of the norm? The below tests reply to these questions.
Here are the results:
| Test type | Technical test | Results |
| Variation of linear cutting velocity | From 1.20m/s to 1.40m/s | Pass |
| Variation of track pitch | From 1.5µm to 1.7µm | Pass |
| Combined variations of track pitch and velocity | From 1.20m/s & 1.5µm to 1.40m/s & 1.7µm | Pass |
| HF detection (asymmetry pitch/flat ratio) | Variation from 2% to 18% | Pass |
| Dropouts resistance | From 0.05mm (0.038ms) to 4mm (3.080ms) | Pass |
| Combined dropouts and smallest pitch | From 1.5µm & 1mm to 1.5µm & 2.4mm | Pass |
| Successive dropouts | From 2x0.1mm to 2x3mm | Pass |
Yeah! Best in class! Not only a handful of drives achieve this performance, the Sony is also the least expensive transport (new) that I tested! I saw the Sony SERVO starting interpolating at high dropouts of 2.4mm and I could not hear anything up to 4mm. Drill a tiny hole in the CD, and the S1700 will continue to read it with you noticing
Sony BDP-S1700/K - Measurements (Coax out, USB and DVD-A as sources)
So we stay in digital domain for these measurements.
For the sake of simplicity, I'll show you only the standard dashboard with my pseudo 1kHz test tone.
First,
from USB key (1kHz @0dBFS 24bits/48kHz):
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As per the HDCP regulations, the signal is reduced to 16bits depth AND 48kHz output. I tried with 96kHz and 192kHz sampling rate test files, and got the same output 16bits/48kHz. We are indeed limited by 16bits/48kHz. At least the decrease of bit depth does not come with significant distorsion, but SNR is now limited to 99dB, as you can see.
Now,
from a DVD-A, it is not the same story at all. Look at the same test tone (24bits/48kHz):
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If the dashboard shows 16bits resolution, it is because of the distortion, and not limitation from the noise floor. Looking at the noise floor level, we are close to 18bits resolution.
This is not the 24bits recorded on the DVD-A. So there is again significant processing here, and that does not to comply with 16bits/48kHz output. Strange.
Problem is that the situation degrades with lower levels of output as the distortion is roughly constant, and not level dependent (not shown). This is weird but means I can't recommend using it to listen to DVD-A, if you still have some. I could not find a firmware update to potentially fix this issue.
In the end, don't expect anything high resolution from the Coax output, use it for CD playback only. And note that a WAV file 16bits/44.1kHz, played from the USB stick, outputs the original unaltered PCM data stream.
Sony BDP-S1700/K - Measurements (CD source with Topping D50III as DAC)
Let me finalize this review with few tests from the output of the high precision DAC
Topping D50III, the Sony BDP-S1700/K being the source, from CD audio. I used the RCA outputs of the Topping.
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As usual, let's start with my standard 999.91Hz sine @0dBFS (without dither) from the Test CD (RCA out of the D50III):
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As I reported with the test of the SMSL PL200, this is near perfection, so close to the original WAV file, and thanks to the high resolution of the Topping. Some distortion (at -135dBr!) might be due to my ADC, by the way, with that high-level test tone.
Let's try at -6dBFS:
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Peeeerfect! You can't dream for more. The limit in the PCM 16bits format here, not the Topping and of course not the Sony!
I'll spare you with more measurements, but just a last one. Look at this magnificent Jitter trace:
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It looks like the one done directly from the WAV file, but no, here we indeed have the Sony feeding the D50III and the result is nothing else but absolutely perfect. Impressive.
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Now, one very interesting thing here, about the "intersample-overs" test which intends to identify the behavior of the digital filtering and DAC when it come to process near clipping signals. Because of the oversampling, there might be interpolated data that go above 0dBFS and would saturate (clip) the DAC and therefore the output. And this effect shows through distorsion (THD+N measurement up to 96kHz). But let me lower the Topping output by 3dB, since we have so much headroom with 16bits signal:
Best of the best! Actually I never performed this test before with a transport and the D50III. And it means what it means: this combo provided me with
the best analogue output I ever witnessed! Even the star
SMSL PL200 started to slightly clip with 3dB overs. And if you're worried that -3dB output volume might decrease max performance, let me reassure you:
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Actually the third harmonic, that we could see from my initial test, is gone
So that is the equivalent of measuring the original WAV file!
Conclusion
You get here
one of the best CD Transport ever made at a very low price, from a highly praised brand. I was expecting nothing special from this Transport, what a biased mistake that was!
Not only the digital output is untouched, the drive resistance to borderline pressed CDs or those that suffered a very busy life, and that many CD Players would have difficulties to read (or fail to), is a HUGE plus.
Only the small clock deviation could be improved. Probably Sony thought about leaving something to please the DIY community?
With a well chosen DAC, you'll be able to benefit from what most of us never had: absolute transparency -- a SOTA CD Player of all times.
And note that all my measurements were performed with the HDMI output feeding a monitor. I tried also without the cable connected, and I saw the same perfection, of course, what more to expect?
Remains the ergonomics, clearly not the best, but if you accept to turn on the TV, it's more than ok. Fact that it plays, OOB and without setup required, a CDA with absolute perfection is something I particularly appreciate.
Never one Sony CD Player failed me, in my reviews. As a CD lover, I can only praise Sony for keeping up with the CD, giving it careful attention. Sony left the market of pure CD Player, but did they, really? I think this Blu-Ray tells us that no. More than 40 years later, their engineers still care about their baby. I love it.
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Somewhere deep down at Sony, there is a piece of code, know as the
Primary Gene, that rules everything out, its internal code name is CDA
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The conclusion of the conclusion is that what I measured, with the Sony and the Topping acting together, made me want to listen more to them. And that is the pleasure I was talking about in the introduction. What if you'd know that after inserting a CD and pressing play, the only thing you'd need to care about is sit, relax, listen, and enjoy? Because what you get is exactly, precisely to the last bit, what the artists wanted you to hear. What a delight...
Enjoy your weekend!
Flo
