MEASUREMENTS: Oppo UDP-205 Part 3: Jitter, some conclusions, discussions, and suggestions.

We've reached the last of the "trilogy" measurement posts I'm planning to make on the Oppo UDP-205 (at least for now!). We've already examined some "microscopic" measurements like the oscilloscope reading of square waves, talked about the filter settings and relative differences. Then we've looked at the RightMark measurements demonstrating excellent low noise level, low distortion readings, good frequency responses, and minimum crosstalk across the different outputs.

With this post, let's have a look at the J-Test results from the various outputs to make sure there are no issues, and of course in the process examine temporal stability with the various digital inputs including USB, ethernet, S/PDIF, HDMI, and of course as a CD player. We will then close off with some general thoughts, suggestions, and opinions around this device and broader about the features that might be worth pursuing in audiophilia.

I. USB J-Test

We start with the USB DAC interface. Remember that these days, USB transfer happens asynchronously, which means that the Oppo (DAC) has the ability to tell your computer or streamer to start or stop audio data transfers as the "master" device. The data is buffered in the Oppo of course, and the DAC has access to the buffer's contents whenever it needs with accurate timing.

Below are the Dunn J-Test results demonstrating the usual 16-bit and 24-bit jitter signals as measured through the stereo RCA, XLR, and headphone outputs from the device.

Have fun pixel-peeping :-). Clearly there's no worry about jitter based on the J-Test results here. In fact, the results look remarkably clean within the limits of my Focusrite Forte ADC used in these measurements. The 229Hz square wave LSB modulation tone is easily seen in the 16-bit J-Test as expected given the high-resolution ability of this device. Minimal "skirting" at the base of the primary signal likely represents the limitation of the ADC more so than the DAC.

II. Ethernet J-Test

This will serve as both showing off the J-Test result from the gigabit ethernet playback (streaming through JRiver 24 with the UDP-205 as UPnP/DLNA renderer), as well as looking at the output quality through the multichannel RCA of the device:

Looks good to me... A tad more jitter than the stereo RCA output above but we're looking at sideband amplitudes 120dB below the primary peaks. I trust this would be outside the range of hearing even for "golden ears" out there.

Remember folks, ethernet audio is asynchronous just like modern USB so I did expect good results. The data is buffered and jitter can be controlled very well as shown in the J-Test image.

III. CD J-Test

Remember back in the day before Y2K when CD and CD-R's were the only hi-fi digital game in town? Remember back then how certain subjective audiophiles would be obsessed about making sure music disks were burned at 1X, 2X or 4X speed thinking that higher speed burns would have all kinds of terrible effects on the jitter? Or how about the importance of gold CD's among other colors (like black) being desirable because of things like data accuracy and the jitter boogeyman?

Well that was then and this is now... Here's the J-Test using a cheap Memorex Cool Colors CD-R spindle burned at 16X played back on the UDP-205 (silver reflective data side and blue label side if anyone wondering):

Looks beautiful... I guess we shouldn't be worried about jitter any more, right? (As my previous measurement with the 17-year old Sony SACD/CD player demonstrated, we actually should not have had any worries about jitter at least since the early 2000's. This fact has obviously not been reflected in the media or companies advertising stuff like femtoclocks and the like.)

IV. S/PDIF (Coaxial and TosLink) J-Test

Alright then... Let's get serious with jitter. How about the old "synchronous" digital interfaces designed decades back?

Note that I measured these through the XLR output to get an even better low-noise look. Clearly we have no worries here compared to the majority of devices out there. Very clean J-Test spectra!

V. HDMI Input J-Test

Okay, we're getting even more serious. We know that HDMI is a complex interface and not known to be particularly good with jitter. For more information about this, have a look at my measurements of the Onkyo receiver back in 2013. Hooking up my Microsoft Surface 3 Pro machine to the UDP-205's HDMI input, there's what the J-Test looked like using foobar playing through the HDMI output using Windows' native WASAPI (event) driver:

Again, I'm looking at the FFT through the XLR output. What can I say? It looks really quite nice again with no evidence of worrisome sidebands or significant noise otherwise. As far as I can tell, there is no need to fear that using HDMI input on this device would result in "jittery" audio output.

VI. HDMI Output J-Tests!

Okay, this is rather unique to the Oppo UDP-205. Remember when we looked at the rear ports how there are actually 2 HDMI outs for this machine?

One for the "Main" HDMI output which will typically connect to your receiver or TV. This one outputs in HDMI 2.0 standard and the other "Audio Only" port is meant to be even lower jitter HDMI 1.4 for audiophiles who demand better temporal accuracy connecting to an external DAC. While I can get ethernet, HDMI and S/PDIF audio inputs to be sent out through those HDMI outputs, USB audio cannot be sent through HDMI out. I suppose this is because the USB DAC portion is somewhat autonomous. Therefore, I'll use the coaxial output from my Squeezebox Touch (with EDO plugin) to connect to the UDP-205 and send the HDMI outs to an external "DAC" for measurements.

The truth is, the only HDMI "DAC" I have here is my Yamaha RX-V781 receiver which is not bad but certainly lower than the quality of the Oppo. Nonetheless, let's hook up the UDP-205 HDMI outputs and see if we can detect a difference in the J-Test coming out of the Yamaha when fed either the Main HDMI or the Audio HDMI:

I can't see a significant difference with the 16-bit test (notice the barely-visible jitter modulation LSB tone due to the much higher noise floor of the Yamaha) but I think it's notable from the 24-bit J-Test that indeed the Audio HDMI shows reduced data-correlated jitter sidebands. Nonetheless, as I have said many times over the years, realistically, I don't think jitter is a big deal at all and orders of magnitude less than the wow and flutter of vinyl playback. It's a testament to the Oppo engineers that they went to these lengths to optimize the HDMI for audio purposes! (For a detailed explanation of what they did, see Oppo's article here.)

VII. Conclusions - objective and subjective performance...

There you have it.

This marks the end of the "trilogy" of posts on the objective measurements of the Oppo UDP-205 4K UHD Blu-Ray player with its plethora of features to satisfy the demanding audiophile (and videophile although for 4K/UHD video the UDP-203 is good enough). Across the board we're seeing exemplary performance from this device in audio performance whether it be the range of well-behaved non-overloading filters, high resolution with remarkable low noise floor, low distortion, and clearly inaudible jitter across inputs and outputs. A well engineered piece of gear that IMO puts many much higher priced items to shame.

Admittedly, there are a number of other measurements I can make. For example, we could look at DSD playback at some point. I didn't bother double checking that the noise floor remains low with 352.8kHz+ sample rates. And maybe it's worth having a look at the MQA performance. Maybe :-).

Subjectively, I've mentioned a few times already through these articles that I believe the UDP-205 produces "transparent" sound. Most of the time, I paired the UDP-205 with my usual set-up through the Emotiva XSP-1 pre-amp, to Emotiva XPA-1L monoblocks into the Paradigm Reference Signature S8v3 speakers for listening with and without DSP room correction.

Yes, Nat King Cole's vocals from The Very Thought of You (Analogue Productions SACD, DR14) was velvety, nuanced, and compelling in highlighting one of the most gifted vocalists of the 20th Century. James McMurtry sounded punchy and raw on the album Live In Aught-Three (DR8) despite what I believe was overuse of dynamic compression. Modern productions such as Camila Cabello's Camila (DR6) sounded like, well, a modern pop album with the usual extensive mid/side processing to expand the stereo image, lots of digital sounds and DSP manipulations. Digging into the older catalogue, Ernest Ansermet's The Royal Ballet: Gala Performances (DR12, 2009 Remaster) sounded great with excellent musicianship on display and remains very enjoyable though the limitations of the 1957 analogue capture could be easily discerned through modern digital reproduction (obvious elevated noise floor, audible distortions here and there with some of the instruments and loud passages). The Bucky Pizzarelli Trio's Three For All in binaural (DR18, 2014) was a real hi-res treat especially over my Sennheiser HD800 'phones; every pluck of the guitar, every strum, every foot tap (eg. on "Body and Soul") easily discerned. The UDP-205 literally does not miss a beat and provides the technical chops to deliver all that was recorded on your digital source. Obviously, I love the music played through this device and have no problem engaging emotionally (IMO emotional engagement is more about one's natural inclination towards the artists and music than the device itself!).

As you can see in the image above, I'm playing the song "Ripple" (ripped from the Grateful Dead American Beauty DVD-A) as 5.1 24/96 audio over DLNA/UPnP through ethernet from JRiver 24. This works quite well and I can easily control the playback with the free Gizmo app with my Android device. However, DLNA/UPnP is not gapless. This is a bit of a problem which I can overcome with having my Raspberry Pi 3 "Touch" playing off LMS for stereo music at least. It is unfortunate that Oppo has not changed the way it plays off the network as I'm sure there have been requests for gapless network playback since BDP-105 was their flagship (at least the last 5 years). Personally, gapless network playback would have been worth way more than MQA compatibility. Oppo technical support has also said over the months that unfortunately Roon streaming will only support stereo and not DSD.

Apart from bug fixes and UHD Blu-Ray updates as needed, I can think of a couple things that would be very nice for Oppo to implement in firmware if possible (after they fix the XLR issue with the current MQA beta firmware as discussed last time!).

1. How about using the front panel LED display to provide a little more information? For example, when using as a DAC, how about showing the samplerate? Like "USB IN 192kHz", "OPTICAL IN 96kHz", "USB IN DSD128", "USB IN MQA 88.2 / 352.8kHz" when the input changes, then scrolling this information when the screen saver is on instead of just the rather bland "SCREEN SAVER" text which is useless when playing USB or S/PDIF audio and the TV is off. A small touch that can also serve as a prompt to users to confirm that unexpected downsampling isn't happening... These small touches go a long way as I'm sure Oppo knows.

2. USB DAC input with multichannel capability? As I mentioned above about the lack of gapless DLNA/UPnP playback (including multichannel) and no multichannel Roon, so, how about multichannel capability as a USB DAC (through the USB B connector, even up to 5.1 24/96 would be amazing)? Considering that we already have all that multichannel decoding hardware with 7.1 RCA connectors and a killer high-quality DAC inside there, it would be a shame not to open up the capabilities as much as possible. If the USB infrastructure allows (hopefully one of the latest 16-core XMOS xCORE-200 microcontrollers), why not throw down the gauntlet? One. Last. Time. [The only product I know that can do multichannel USB is from exaSound.]

With transparency of such a high degree achieved, it's really not 2-channel "sound quality" that should be the focus of the audiophile hobby going foward. There are really no issues to solve IMO when it comes to digital players and streamers other than improving convenience, reliability and lower cost. It's time to expand features that improve the immersion. Yes, I know that multichannel is hard to do well and many will not bother with it. But it is without doubt the "next level" of sound quality once an audiophile wants to go beyond the limits of the stereo experience.

As one who aims towards the goal of "high fidelity" with associated expectations that a device be objectively accurate, I'm very happy with the UDP-205 for "reference" listening, knowing that as a digital source, it will neither add nor subtract from what's in the audio data. I must say that I would never consider doing any kind of "mod" to this device (eg. adding tubes or whatever to the analogue output stage) given the results I've seen. There's really no "improvement" that would enhance the transparency. In all likelihood, one would see an increase in the noise floor and reduced resolution. I know some people prefer a "warmer" sound, but in my opinion, that's simply damaging to the fidelity achieved; just add an EQ and tune to preference! Note that I have listened and measured the Oppo BDP-105 pre and post tube modding years ago; we'll talk more about this next time.

It is unfortunate that Oppo Digital has decided to wind down operations. Presumably the "last batch" of these players scheduled for August 2018 will be the final opportunity to purchase one new. I think for audiophiles and videophiles looking for rational products that represent excellent value and quality engineering, the Oppo brand will be sorely missed.

-----------------------------------------------

Looks like Qobuz hi-res streaming is coming to the USA... And it's based on FLAC. Wise. Will be an interesting battle for the lossless and hi-res market share between this and Tidal once launched.

Anyone know if Qobuz is going to be available in Canada as well?

Summer is here... Time to lay back, relax a little with a cold one, and enjoy the music of course. Depending on how things go around here with work, I might go on vacation for a little bit over the next couple months :-).

Addendum June 24, 2018:

As requested, here are the WaveSpectra settings if anyone wants to try with their own ADC system...

Note the 5-18kHz frequency range I'm looking at. WaveSpectra maxes out at 131072 points. Yes, I could send the data offline for 1M+ point analysis but I figure the realtime result is more than good enough for the purposes of a consumer.

On the Play/Rec tab, I have the Focusrite Forte using ASIO and 24/192, stereo recording (not shown).

Enjoy...