QUICK COMPARE: AVC vs. HEVC, 8-bit vs. 10-bit Video Encoding

As I mentioned in the last blog post on HEVC encoding in response to "Unknown" in the comments, I do believe there are potential subtle benefits to the use of the 10-bit x265 encoder in Handbrake even with an 8-bit video source. I figured I'll run a very quick test to show what I've seen...

MUSINGS: End of 2016 - Video Encoding (HEVC 10-bits, the HDR "Trinity"), Multichannel Streaming, and Other Thoughts...

For those of you into video, I suspect you're already very excited about the "next generation" H.265/HEVC encoding format. About a year back, I already made mention of the impressive results I was seeing with playback of HEVC on the Skylake HTPC I was putting together. A year down the road, we see the ongoing development of software harnessing the power of the new encoding technique - even lower bitrate for very high quality output.

As we say goodbye to 2016, I thought I'd just "shoot the breeze" a bit and meander down some related topics. Let's talk about video encoding, what I've been doing, what I've found useful/interesting, and some speculation of what I think would be in the not too distant future as it applies to high dynamic range (HDR) video...

MEASUREMENTS: Yamaha RX-V781 Receiver (a look at the pre-out quality)

With the upgrade recently to a 4K TV, it was alas also time to upgrade the surround receiver system I was using. A number of years ago, I bought a used Onkyo TX-NR1009 which I wrote about. It has served me reasonably well over the last few years but not without some issues. The most bothersome was the fact that the HDMI board died last year and it had to be sent back to Onkyo for a board replacement. Thankfully, despite the machine being released around 2011, Onkyo still honored the repair as apparently this is a common problem acknowledged by the company. Not good that the product was defective due to an engineering oversight (soldering & overheating issues), but at least the company "manned up" to the problem.

These days, to make full use of the surround sound system connected to a full-featured 4K TV, the best way is to upgrade the receiver to be compatible with the latest HDMI 2.0 specification with allowance for 4K/UHD @ 60Hz, HDCP 2.2 copy protection compatibility, as well as passing through the full video signal - including full color information (Rec. 2020/BT.2020 and HDR). (For those new to this kind of AV talk, you might want to review the 4K tech article from a few months back.)

Unfortunately, the Onkyo was only good to HDMI 1.4. It was time to upgrade to one of the new receivers... And this is what I found on sale locally:

It's a new model year 2016 Yamaha RX-V781 (current price ~US$700).

MEASUREMENTS: What does a US$500/watt stereo amplifier sound like? (Vitus Audio SS-010)

Behold!

MEASUREMENTS: On the value for ethernet "galvanic isolation"...

Ponderous. That's the adjective that comes to mind so often when I visit audiophile sites and come across yet another tweak suggestion. Over the years, there have been many such nuggets... Ideas like using a battery to power devices to make them "sound better" in supposedly very significant ways. Switching mode power supplies in general are said to be "bad". USB carries with it significant noise so we should to buy certain "filter" type devices (Audioquest Jitterbug, Uptone Regen, etc...). Server computers sounding different using the same high quality DAC when there's no DSP processing applied to the actual digital signal. OS optimization tweaks "reduces jitter" and again "sounds better"... The possibilities are endless!

On a few occasions, there are nuggets of truth in some of these ideas. For example, yes there is jitter to be found in some circumstances (small but measurable amounts like with S/PDIF and HDMI). Yes, sometimes you can detect noise from computers situated close to a DAC. Realize of course, many times the "solutions" advocated do not necessarily fix the problem. For example, I have yet to see a situation where a fancy passive piece of cable can fix jitter. And more often than not though, the subjective advocate/testifier/witness appears to magnify the purported effects to such extremes in the hopes of drumming up interest in what really should be rather insignificant issues. (Why folks would do this will be left to the reader to decipher... :-)

Which leads to today's topic... Ethernet galvanic isolation.

Moving on to 4K: A look at the Sharp LC-75N8000U UHD "HDR" TV.

As you can see above, I made the move to a larger 75" screen 4K/UHD-TV from my 55" LG 55LW5600 purchased in 2011. Not sure if it's as appreciable in the image above, but the extra 20-inches diagonally make a huge difference in the movie watching experience from the sofa! (The camera focal length and perspective clearly makes a big difference in pictures...)

This is the Sharp LC-75N8000U. As I discussed recently, I've been looking around at 4K TV's for quite awhile. Admittedly, I just could not resist the price to give this a try at least (currently only ~US$2000 on Amazon)! With this post, let's have a look at this display and I'll throw out a few thoughts...

MEASUREMENTS: Crystal Cable CrystalConnect Micro 1m Interconnects... Differences vs. Generics???

Alright guys... As you know I've measured cables in the past - why audiophile magazines never seem to get around to this is anyone's guess :-). And as I summarized here, there really hasn't been evidence of a meaningful difference between various cables of all sorts.

Over the years, I have tried to measure cables which are considered "audiophile quality" when I can get my hands on them. You know, things like the Synergistic "Tesla" power cables, or these Kimber 8TC speaker cables. Note that obviously if I really wanted to, it's not like there aren't a selection of audiophile stores locally in Vancouver. Without evidence in my own subjective experience or reasonable theory that major differences are even possible, I'm obviously not going to go out of my way to test these things when there are so many other topics to learn about and explore! When I had the opportunity from a friend to hang on to these cables for awhile and test them out, well, why not? Especially since he's had these for years and they're well "broken in"! :-)

Behold, the Crystal Cable Micro; we're often reminded in reviews that Crystal Cable is based in The Netherlands (parent company International Audio Holdings which also owns Siltech):

Notice the small round "silver billets", all part of the typical Crystal Cable esthetic. New models have a more ovoid shape.

MEASUREMENTS: HiFiBerry DAC+ Pro, PCM5122 digital filters & further thoughts on filtering...

A summary slide from this presentation slide set. Just a reminder of the general desirability of digital filters providing higher accuracy compared to analogue...

Thanks to Jim Ambras in the discussion of the measurements for the Raspberry Pi 3 & HiFiBerry DAC+ Pro for pointing me to some settings available! So in the "Wait! There's more..." department, there are some "advanced" settings available in Alsamixer for the DAC+ Pro I2S HAT board you might wish to experiment with. Let us have a look at the different digital filters built into this very affordable DAC and how it changes the sound objectively...

MUSINGS: Keeping it simple... MQA is a partially lossy CODEC.

Connoisseurs of French cuisine will know this guy...

In the last few days, I noticed my inbox containing a number of questions again about MQA... Presumably due to a combination of the last blog post with Agitater's comments and I guess some news on MQA after the recent Rocky Mountain Audio Fest 2016 where a number of companies were playing MQA and apparently allowing A/B comparisons of sorts.

I say "of sorts" above because it seems from descriptions the best comparisons were more along the lines of using the same file but with MQA decoding turned on/off "on the fly". Not an actual native 16/44 CD resolution file vs. MQA decoding in a volume controlled state using the same source mastering of course. Remember, the processing itself likely affects the sound quality (indeed, Meridian/MQA wants us to believe MQA processing will still benefit playback even without a decoder and folks testify about this as well). My little ABX test suggests small differences as well.

So, let's just keep it "simple" ("but not simpler" as per Einstein). Here's the bottom line for us consumers IMO...

An opinion about Audio & MQA by "Agitater"... (And a few words on DACs sounding similar.)

I suspect many of you hang out at the usual audio/audiophile message forum "watering holes" as I do. Among the chatter, every once awhile though, I run across something that a thoughtful poster obviously took time to compose and express such that I cannot but wish the message could be shared in a broader context beyond the individuals visiting the thread.

Last weekend, as I was reading the latest on Steve Hoffman's forum, I came across this opinion piece by "Agitater", a fellow Canadian out east in Toronto (I'm here in Vancouver on the west coast). Therefore, with permission to reproduce here, a comment from a fellow audiophile taken from a discussion on MQA (see page 12), but clearly going beyond into his views of the audiophile hobby and current state of affairs. So, in response to a comment about a recent article in The Absolute Sound and someone saying that Robert Harley (Editor-in-chief) is "one of the best in the industry", Agitater had this to add...

MEASUREMENTS: Raspberry Pi 3 & HiFiBerry DAC+ Pro (Audio Streaming)

Last week in the preview, I introduced you to the Raspberry Pi 3 Model B with the HiFiBerry DAC+ Pro HAT board. You see above a picture of the boards assembled but in the "naked" state before installation in the case. As I mentioned it doesn't take much time to put this all together on the hardware side, and just a bit of tinkering with Volumio 2 was all that was needed afterwards to get the DLNA/UPnP streaming working over the wired ethernet (a little fiddling with the Volumio hotspot if you want to use WiFi - not recommended for hi-res audio). Since the software is still in development, I noticed that messing with network settings could lead to connection issues. But once it works, it has been stable.

As promised then, let us now put this device to the test and see how it performs objectively. What level of "high fidelity" does this streamer/DAC combination perform at?

PREVIEW / SET-UP: Raspberry Pi 3 Model B & HiFiBerry DAC+ Pro

As you know from discussions a few months ago, I'm a fan of the credit-card sized SBCs (Single Board Computers). I've already spent time discussing the inexpensive but powerful ODROID-C2 and the setup of this computer as a streamer to my TEAC UD-501 USB DAC using Volumio 2 including the excellent measurements one can get with this combination.

Today, let's talk about this very affordable combination:

Pi 3 Model B (left), HiFiBerry DAC+ Pro (right) boards.

What you see above are 3 items:
- Raspberry Pi 3 Model B - SBC computer, <US$40
- HiFiBerry DAC+ Pro - DAC "HAT" (Hardware Attached on Top) <US$60
- Inexpensive Raspberry Pi case with allowance for the HAT - ~US$10 - red to remind me I have a Raspberry in there :-) - here's a black version

Basically, we have here the hardware for a high-resolution audio streamer with integrated DAC for around the US$110 price point before taxes and shipping.

Assembled:

MUSINGS: 4K UHD TV, HFR, 3D, HDR, etc... Thoughts on video technology and the consumer.

As you saw a couple weeks back, when in China, I visited a number of electronics stores, especially the "big box" places in Beijing and Guangzhou. Many of these stores had on display a whole floor of 4K TVs made by all kinds of brands (many local China brands like TCL, Hisense, Skyworth, Changhong as well as the usual Samsung, LG, Sharp, Sony, etc...) and one could easily walk around and compare image quality. Of course, this is ultimately a limited comparison because the TVs are all displaying the manufacturer default settings and this usually means extremely bright, color saturated, extreme sharpness, and max'ed out contrast settings playing typically pristine demo videos so as to catch the consumer's gaze.

Even though this is primarily an audio blog, I see no need to confine ourselves to just one sensory modality... I've been wanting to upgrade to a 4K TV for awhile, certainly since my 4K computer monitor upgrade early last year. For today, I thought it would be good to think about the world of TVs and where the home visual technologies are leading us. Let's talk about some of the technology around visual quality and the parameters we should be keeping in mind, and perhaps even consider the future and what's down the pipeline. Perhaps most importantly, I like to think as a consumer in the big picture and even speculate a little bit about what might happen down the road.

RETRO-MEASURE: 2006 Apple iPod "Classic" 60GB 5th Generation

Here's a very cool Steve Hoffman forum thread I came across a few months back which "inspired" this post.

I appreciate the iPod. It was quite the gadget back in the day, foreshadowing the rise of touchscreen "gesture" devices. I remember being impressed by the intuitive scroll wheel (introduced in late 2001) which over time transformed to the "touch wheel" by 2002 then the "click wheel" by 2003 and of course "multi-touch" by late 2007 as it joined the family of touch-screen devices. By the time it became the Touch the iPod basically got transformed into an "iPhone Lite".

Looking through my box of gadgets, I found my old iPod "Video" 5th Generation (model PA003LL) from back in July 2006 (I know this because I got free engraving on it). It's got a 60GB original hard drive installed. Color screen, 2.5", with 320x240 resolution. Firmware version on this baby is 1.3, presumably the latest version since iTunes didn't ask me to update. It still charges fine but there is noticeable degradation with the battery life. The central button feels a little "sticky" these days after many many hours of use over the years, but still functions well. This is the penultimate hard drive based iPod superseded by the iPod "Classic" (6th Gen) in 2007. It has been said that this 5G and "late 2006" 5.5G models with 80GB HD were perhaps the best sounding on account of these models being the last to use a Wolfson DAC internally.

Of interest I think is that Stereophile reviewed and measured an older version of the iPod back in 2003. That was the 3rd Generation they looked at with of course earlier DAC chips.

MUSINGS: A Technophile's Breeze Through Asia 2016...

Hey guys, as I've noted over the last while, I've been in Asia over summer. I spent some time in Taiwan, then China, and ended the trip in Vietnam. As usual, when I travel, I keep an eye open on interesting technology sights and sounds, especially what's new and available in the world of audio; if anything.

For fun, here are a few pictures and comments from the places I visited that might be interesting from the perspective of a consumer technophile... A "streetside" spectator's view if you will. Not intending to be extensive of course, but a sampling of thoughts over the month overseas.

Taipei:

My Favourite Movie Audiophile Scene

Well, I had a great time away in Asia and glad to be home in Vancouver!

Just wanted to share with everyone my favourite "audiophile scene" from a movie :-). It's at the start of the Chinese movie Infernal Affairs (無間道, 2002). I remember watching it at a buddy's place when it first came out - maybe around 2003 and was just blown away by the movie! I guess Martin Scorsese must have been impressed by it as well to come up with The Departed in 2006 which of course won him the Best Director and declared Best Motion Picture in the Oscars.

As often happens with first impressions, I much preferred the original movie situated in Hong Kong - shorter, more concise, less of Leo DiCaprio's brooding, more cinematic than gritty realism - all subjective of course. Starring Andy Lau and Tony Leung, the opening scene where they meet each other in an audiophile store is a "classic" for me as an audiophile moment... Featuring a vacuum tube amp, audiophile female vocal, "transparency", soundstage and imaging, veils lifted with small tweak, uncontrolled sighted listening and $4000 cables :-). But at least the guy got a tip on where to buy cheaper speakers! Also a nice view of the electronics street in HK circa early 2000s.

By the way, the song is "The Forgotten Time" (被遗忘的时光) by Cai Qin (Tsai Chin / 蔡琴). Available here among other similar compilation CD's...

Enjoy as we end off August and the summer vacation season... :-(

MUSINGS: Convenience, lossy audio, societal trends, and worsening sound quality?

IMO, a realistic graph of audio formats and quality first discussed here.

Last week, as I was browsing the internet catching up on the news after a long day out doing touristy things in China, I came across this interesting post on Stereophile. A whimsical look at the proverbial crystal ball and presenting a rather dystopian audiophile future of 2116. For some reason, the protagonist seems to be a hippie and references to Baby Boomers are made. As if these terms would even be of contemporary significance by that time! Plus it's presented as if high quality sonic reproduction would be absent in a century's time!

The basic lament is the tiring belief that we don't seem to care about sound quality any more as a society, the quality is "deteriorating", and that ultimately it's all got to do with "convenience".

But is this true?

Short and sweet:
NO, I don't think so.

I suspect it's much more complex and worth putting some thought into...

MUSINGS: Do "audiophile" computer-based players make a difference? On "Everything Matters" and wisdom.

Since publishing the results from the NUC measurements a week back, permit me to discuss the topic of "audiophile" music servers, streamers and transports - specifically addressing the idea some have that they make a significant sonic difference.

As audiophiles, we've all seen them reviewed in the various websites. Names like Aurender, Antipodes, SOtM, Small Green Computer, Baetis Audio for machines that run either Windows or Linux, or more customized non-PC looking devices like the Auralic streamers, SONORE microRendu (Wow! So much hype!), and established audio companies within the arena like PS Audio, Ayre, Bryston, Simaudio, etc. Even JRiver sells their customized NUC server/player, called the Id.

MEASUREMENTS: Intel NUC [6i5SYH] (and Audio)

Packaged contents of the NUC - mounting screw, universal power jack attachments in the bubble wrap, metal VESA mount plate under the power supply, basic instructions.

Like most of my computer upgrades lately, it's not because I need the speed, or expect much power saving, or necessarily to silence a noisy machine... Speed, efficiency, and quietness have been achieved to the level I'm satisfied with for years now! No... It's because I wanted to upgrade my work computer to something that handles 4K resolution :-). As discussed here and here, over the last year, I've been transitioning to what I think is going to be the target resolution for the foreseeable future (in a way very much like how audio CD resolution has been completely fine for decades). Beyond 4K, the reasons for even higher resolutions drop off exponentially based on the physical limitations of vision. (Of course, beyond spatial resolution, HDR color range and contrast ratios are important and those are catching up nicely.)

A few months ago, I decided to upgrade an aging 24" Dell monitor with a new ASUS PB287Q - quite a nice reasonably priced 28" 4K unit. (If I were to buy today, I would take a good look at the LG 27UD88 or consider the 21:9 LG 34UC98.) Alas, for the last while, I've been running the monitor at 1200p resolution with the current work computer. Though the upscaling doesn't look bad, it's noticeably compromised compared to actual native resolution of course.

As a simple way to upgrade instead of buying all the parts and assembling a new computer, I decided to go with the current generation Skylake NUC "Next Unit of Computing" - the Intel NUC6i5SYH which houses the Core i5-6260U processor with the Iris Graphics 540 integrated GPU. This NUC case allows for a 2.5" SSD/HD and M.2 SSD. If you want an even smaller, flatter unit, consider the similarly-priced NUC6i5SYK, the same innards but with a smaller case removing the 2.5" bay so the internal SSD will have to be an M.2 card.

A Response RE: MQA, "blocking" of Meridian's responses, and A/B Tests...

Just a quick note (remember... I'm on summer holiday and all!). Someone passed along to me this article from Hi-Fi+. It's an interview with Bob Stuart and Morten Lindberg (2L) apparently conducted in May. I'm bringing this up because the first Q&A is about "detractors" and there's this curious response:

BS: We’ve had some detractors, but frankly where we sit, we’ve been actually rather pleased how few. We’ve come in with an inconvenient truth – digital audio hasn’t been done right – so we thought the community might attack us. And one person put up a long blog about MQA that was just inaccurate, but blocked all our replies. As we say in England, “That’s not cricket!”

Now I don't know if this is definitely in reference to this blog and specifically to posts here and here but over the last few months I have heard this claimed... That somehow Meridian tried to post a response but the message was "blocked" (presumably by me) and that presumably the message would have contained corrections and answers to the issues raised.

MEASUREMENTS: Focusrite Forte USB Audio Interface (ADC & DAC) + Summer Musings

Product shot from here.

A few weeks back, I mentioned that I grabbed one of these Focusrite Forte USB2 audio interface units for some home recording projects I wanted to do. Beyond using it as a measurement device, my old Creative E-MU 0404USB was being used for some of these recordings and I figured it was time to upgrade to something new since a couple of the analogue pots were getting a little scratchy and I figured an all-digital device like this would allow me to more accurately adjust the volume on the microphone pre-amps (indeed it has worked out very well!).

A size comparison.

MUSINGS: Digital Interpolation Filters and Ringing (plus other Nyquist discussions and "proof" of High-Resolution Audio audibility)

A couple weeks ago, Whackamus posed this interesting comment and question which I thought would be a good topic to discuss and explore in greater detail and with some examples/samples:

"I've been reading your blog for years. Or for almost four years, at any rate. I have to thank you for doing what you do. I've likewise always wanted to ask you a question, too, but I don't know how the bleep to to contact you. In any case, since I've been fretting over it afresh, I thought I'd just post it here. If you ever do decide to get to/address it, that'd be great. If not -- hey, no sweat. :)

In any case, I read the following (tonight) on the Stereophile forums:

"I personally think that MQA has some noble goals, in terms of getting as close to the original master as possible, but I think that is far less important than the elimination of the damaging pre-ringing distortion. This has been the bane of digital playback for 30 years, and over-sampling and various filter techniques have tried to deal with it, with limited success."

I won't say that I've never heard ringing -- because I probably have -- but I will say that I've never explicitly said: "Aha! Eureka! Thar be ringing!" Because -- outside of maybe a blurring during transients? -- I have no idea what it sounds like. But my question is less about MY having heard ringing than about the AUDIBILITY of ringing -- pre, post, or otherwise. In a quality DAC (which I've got to assume most of the folks posting on Stereophile.com have access to), how audible are ringing effects? Or, rather, how COMMON are they? I kind of imagine that the Meitners, Lavrys, Levinsons, Stuarts, etc. of the audio world take great care to minimize (pre-/post-)ringing effects and to eliminate ringing in the audible realm. I likewise imagine that both such things are doable, inasmuch as most of us have been enjoying digital audio for decades now. But the Stereophile poster makes it seem as if ringing is the apodeictic bane of digital audio. What am I missing?"

The Vancouver Audio Show 2016 (June 25): Pictorial & Comments (the MQA Demo, and Show Musings)

As I mentioned a few weeks back, the folks at the Chester Group have put on the Vancouver Audio Show again this year at the Hilton Metrotown (in Burnaby). I must admit, it's not the ideal weekend for an audio show. Summer holidays starting, weather getting better, this is also the opening weekend for the Vancouver International Jazz Festival... I guess the "music lovers" can enjoy the great outdoors while "audiophiles" can hang out indoors checking out the gear :-). Last year, they had it in May which probably makes more sense.

I spent most of Saturday at the show. It was a blast meeting up with Mitch (aka Mitchco on Computer Audiophile, recent eBook on the use of DSP in the listening environment) and wandering the hallways through the various showrooms with my buddy Phil and catching up with my dad who was there as well. As I mentioned before, I think Vancouver has the luxury of a decent selection of "high end audio" stores already but it's certainly nice to be able to come to one place to check out the gear and listen to what's new.

MEASUREMENTS: Gigabyte GA-Z170X-Gaming 7 (Creative Recon3Di) - Motherboard DAC / Audio Output

A number of months back, I rebuilt my HTPC set-up to run the new Skylake i5 processor. I thought it might be interesting to measure the motherboard audio output of the Gigabyte GA-Z170X-Gaming 7 to have a peek at what a typical modern "gaming" motherboard's audio output performs like. Here's the back panel and a picture of the MoBo:

Rear panel - note the blue TosLink cable, beside it the analogue phono plug for stereo out...

As I described in that article, the Gigabyte motherboard forms the foundation for the the new build. Technologies built into the new "consumer performance" Intel Z170 chipset includes compatibility with the new Skylake processors of course, more PCI-E lanes, up to 10 USB3.0 ports, up to 3 M.2 interfaces for SSD storage, etc. As I mentioned previously, this motherboard also has HDMI 2.0 + HDCP 2.2 capability (firmware upgrade available now and ready to go), plus there's Thunderbolt 3 out from that little USB 3.1-Type C port - very cool.

If you look at the Gigabyte literature on the website, you see that they're also hyping up the audio output somewhat. Upgradable opamp, Creative Sound Core3D quad-core processor (for 3D positional sound), high-end capacitors (Nichicon MUSE MW "Acoustic Series"). After installation, the audio device is identified as the "Sound Blaster Recon3Di" [presumably the 'i' indicates "integrated"].

How good is the analogue output from a modern computer motherboard like this?

MISCELLANY: Vancouver Audio Show, Focusrite Forte Ahead, HEVC, Surround Audio CODECs...

Hey there guys, life and work is busy so I thought the post this week would be to cover a few miscellaneous thoughts from the last few weeks.

First, as you can see in the picture above, it's coming again this year! I guess the Vancouver Audio Show went well enough last year that we're going to see a repeat performance with the Show this year... Nice. I remember that there was no mention of the Show at the usual audiophile websites so I figure I'd let everyone know it's coming. Thankfully here in Vancouver we do have a few audiophile stores with good showrooms. Plus with the city (as well as much of the West Coast of North America) being a place where rich Asian investors like to park their cash (just look at the housing market!), it's a nice place to show off the goods... Of course, it also doesn't hurt given the relative strength of the US dollar to attract a few Americans up from nearby Seattle.

MUSINGS / ANALYSIS: Is there any value to 176.4 and 192kHz Hi-Res audio files? A practical evaluation...

Check out this article from 1998 written by the founder of Earthworks, David E. Blackmer (1927-2002).
 
Although I believe some of the contents in the article above are debatable, in the years since 1998, high-resolution, high samplerate audio has of course become common-day reality for audiophiles. As I expressed years ago, I do like the 2xCD samplerates like 88 and 96kHz. But as a result of realizing that 176.4 and 192kHz songs were not being streamed properly with my Logitech Media Server with BrutefirDRC set-up described a few months back, I started asking myself, what is it we would be missing if these albums were downsampled to 88.2 and 96kHz?

Put another way, we could ask "Is there something musical about the highest octave in these 4x samplerate files?" This highest octave for 176.4kHz files would be audio containing 44kHz to 88kHz, and in 192kHz files from 48kHz to 96kHz.

Updated Room MEASUREMENTS & MUSINGS on Importance of Sonic "Accuracy" and the Audiophile.

Chapter I: Another Round of Room Measurements...

Recently, I acquired some more LP's, got a few more IKEA Kallax storage units for said LP's and put up some art as well. Here are front and rear shots of the sound room the other day...

With the physical changes and reviewing my post from last year regarding the use of (((acourate))) along with suggestions made by Dr. Uli Brueggemann and Mitch Barnett (aka Mitchco), I decided that it was time to re-do the room measurements and see if I can incorporate the important suggestions - 48kHz sampling rate for the measurements, sweep range of 10-24kHz, and incorporation of the subsonic filtering at 15Hz. If you're wondering, the dimensions of the room are ~20' x 15' x 8' with a slight frontal tapering as shown; not a huge room by any means and not ideal dimensions but at least it's not squarish/cubish (here's a study on room dimensions and acoustics). It's in the basement of my house, built as a family media room with extra thick walls to reduce sound leakage when the kids are asleep at night (I pretty well can run the sub at reference levels with kids asleep upstairs at night so long as I close the door to the basement). The main speakers - Paradigm Signature S8v3's - are 7.5' apart up front, and the sweet spot is approximately 9' from the speakers arranged like an isosceles triangle. I make sure there is decent amount of space between the couch and the rear LP storage (>3'). [As you can see, I have the ~15-year old rear full-range Paradigm Studio 80v3's back there.]

MEASUREMENTS: ODROID-C2 with Volumio 2, and USB digital music streaming.

ODROID-C2 & unused "Fujifilm" 5V 1.0A wallwart ready for testing...

For those following along, you're recall back in March, I purchased a Hardkernel ODROID-C2 Linux-based credit-card sized single-board computer; the hardware described in my preview. I loaded up and customized the machine with Volumio 2 (RC1) a couple weeks back. And now as promised, I'll be showing some measurements using this machine with my TEAC UD-501 DAC. (Note that there has been a new Volumio image update since my last post. The current version is "VolumioRC1-fix-2016-05-03-odroidc2.zip" found here. Only fixed some boot issues apparently.)

Before I begin, let's discuss what we're trying to figure out objectively here... It has been claimed by some that the USB interface (which the ODROID will be streaming through to the DAC) can be "bad". Supposedly, it's electrically "noisy" (of course a noisy fan and spinning hard drives are also very bad). And, this is especially "bad" with computer audio because computers are electrically noisy devices and will end up polluting the output from your DAC. Hence, by this reckoning, a general-purpose computer isn't supposedly a good thing to have doing high-fidelity audio duties. Furthermore, it has been surmised by some that power supplies can be problematic. Specifically, an inexpensive switch-mode power supply (like the one in the picture above) can be noisy and again, will have deleterious effects on the sound quality.

It has been said that devices like the recently released Sonore microRendu among more fancy audio streamers like the Auralic Aries line of devices can "sound" better because they reportedly take into account the various sources of noise and supposedly have optimized hardware/software. True or not, the price of such "audiophile" grade devices can be rather substantial especially when it's a device without internal storage and acts as a digital conduit to feed a DAC.

MEASUREMENTS: Music servers possibly using UDP packets? Issues for music streaming?

Original from Obaida's Blog.

Qmax last week raised an interesting question about UDP (User Datagram Protocol) and DLNA/UPnP servers, one of the basic "Transport Layer" protocols for data transmissions used for Internet communications. We are likely very familiar with TCP (Transmission Control Protocol) in our day-to-day lives. This is the transport protocol that carries data off our NAS drives, transmits the web pages we read, and ensures integrity of our E-mail data...

What we might not be as familiar with is this other UDP protocol of communication. Whereas TCP is "connection-oriented" and "unicast" sending data between a server and a client through handshaking, UDP is a "connectionless" system where data is "streamed" across the network with potentially multiple destination addresses ("multicast") but without a need for bidirectional communications to address re-transmission in the event of errors detected in the stream. UDP is typically used in broadcast streams like Internet radio, streaming video, VOIP telephony, and multiplayer video gaming because the occasional data error is acceptable and doesn't require re-transmission. Or in the situation with video games, it's all happening in real-time and it's actually preferable to drop a packet here and there than waste time re-transmitting and potentially causing a deterioration in the action. Another use for UDP is with DNS service using small packets. It's faster, and uses less data bandwidth across the worldwide network overall.

SET-UP: Low Power Linux Audio Player (ODROID-C2 & Volumio 2)

As you know from a few weeks back, I got myself one of these little single-board computers (SBC) - the Hardkernel ODROID-C2 - and posted a PREVIEW on it. As described in that article, I had flashed a copy of Volumio 2 "Release Candidate" (0.861RC1) to my SDHC card and have been streaming music to my TEAC UD-501 DAC in the music room for the last while.

Originally, I was going to publish both the contents in this post as well as measurements but it quickly became obvious that this was going to be too unwieldy (plus the day job got very busy)! As such, let me talk about the basics of the setup here today along with a few changes you might want to try if you're streaming from one of these Linux-based network machines. Then later, we'll get to the measurements...

Note that although I'll obviously be specifically addressing the ODROID-C2 I have here, the software is portable and at present, the good folks at Volumio have software images for many low-power computers including: Raspberry Pi, Beaglebone Black, Cubox, ODROID-C1+, etc... Just check their site to see if your machine is supported with a ready-to-use OS/app image. I've been informed that RuneAudio will also have ODROID-C2 support ahead (maybe as early as this weekend), so keep an eye on that one as well!

RETRO-MEASURE: 1994 Sony MDP-750 LaserDisc / CD Player [and further thoughts on the importance of objectivity]

Okay everyone... For this week, let's go old skool! Feast your eyes on this baby:

Notice the microphone input to the right - karaoke, of course...

That, friends, is the Sony MDP-750, a "vintage" LaserDisc (LD) player manufactured in February 1994 "Made in Japan" according to the label on the back. My dad bought this unit when I was still in university.

In 1994, S. Africa held interracial elections and Mandela won. The IRA declared a cease-fire in Northern Ireland. Kurt Cobain committed suicide. ER and Friends debuts on TV. Doom became a hit videogame launching many future FPS's. W3C (World Wide Web Consortium) was founded. Netscape was founded. Yahoo was launched. The Pentium was found to have some flaws in math calculations! Of course, who can forget? O.J. Simpson gets arrested for murder charges after driving around L.A. in his white Bronco. My, how time flies!

Although my family had owned a couple other CD players before this device, all the previous optical media machines have since died. This machine is built like a tank (weighing in at >21lbs) and still plays LaserDiscs like a champ! I opened it up to check on the gears and cleaned up some dust accumulated over the years.

PREVIEW: ODROID-C2 Single-Board Computer... [And an obligatory MQA addendum.]

Over the last year, every once awhile someone will come and ask me when I was going to try out a Raspberry Pi as a streaming replacement for my Squeezebox systems... Certainly I've been looking around and while I was relaxing in Puerto Vallarta a few weeks back, I decided to leisurely check online the varieties of these low-cost single-board computers (SBCs). Here's a pretty good list of recent SBCs on the market to get a feel of what's out there in early 2016.

Without a doubt, the Raspberry Pi computers are the current reigning champions in popularity. They announced 5 million units sold back in early 2015. The recently released Raspberry Pi 3 looks excellent. Plenty of support, reasonably fast quad-core Broadcom BCM2837 64-bit ARMv8 1.2GHz, decent but not impressive 1GB RAM, OK 10/100Mbps ethernet, and convenient wireless 802.11n WiFi with Bluetooth 4.1. The list price should only be about US$35 for one of these but due to worldwide shortage, there's a bit of a markup currently (very common supply-demand issue of course).

But looking around, another little computer caught my attention - the US$40 ODROID-C2 from Hardkernel, a South Korean company. This was just released in March 2016. I was able to get it here in Canada from Diigiit Robotics but I see that they're now out of stock and like the Pi 3, prices have become elevated. Here's the block diagram for the C2:

All technical details including schematics can be found here.

As you can see, it's a reasonably powerful little unit which easily can outrace the Pi 3 computationally (some benchmarks here compared to Pi 3). Quad-core Amlogic S905 CPU with 64-bit Cortex-A53's running at 2GHz, 2GB of DDR3 RAM, Gigabit ethernet, and a video subsystem capable of HDMI 2.0 4K/60fps output and hardware decoding for H.265 (750MHz Mali-450 "pentacore" GPU). Unlike the Pi 3, this unit does not have built-in wireless communications. Micro-SD card (supports UHS-1 speed) can be used or faster e.MMC 5.0 (400MB/s interface) module for flash storage. There's also an IR receiver built-in for remote control of features like volume adjustment.

So I figured... Why not? Let's get one of these little guys with the goal being to run a simple Volumio streamer out of it (I think we'll be seeing RuneAudio on this device soon also). Here's what I got:

The ODROID-C2 with clear plastic case. Note how small this computer is - about the form factor of my Costco card :-). Around the same size for the Raspberry Pi...

MUSINGS: USB Audio Gremlins Exposed: Beyond 1s and 0s? - Analysis of Industry Content

Fear, Uncertainty and Doubt in digital audio...

[This article has been modified over the years with reduction in the quotes from an article that appeared back in 2016! Even though AudioStream has been dead for years, I suspect iFi really doesn't like this article. I've received a number of claims that this article has been in "violation" of some kind of terms reported to Google. To be honest, I'm not sure what's the problem since free speech does allow me to quote from published articles and ads for the sake of voicing my own commentary. --- December 2023]

Oh my... Run for the hills folks! Didn't you hear? USB is a horrible interface for audio purposes!

Hmmm... At least that's the kind of interpretation one might be tempted to consider after reading this "truthy scientific" article on AudioStream ("USB Audio Gremlins Exposed: Beyond 1s and 0s, by iFi Audio")! What can I say? Brutal! Nice example of content from Industry to instill some measure of concern among susceptible audiophiles.

Okay, let me first say that I'm not claiming that USB is perfect - nothing is... You could run into issues. But the fact really is that these days, with a decent asynchronous DAC (what decent audiophile USB DAC these days isn't asynchronous?), one should not be concerned with data errors, jitter issues, and I have yet to come across noise pollution from a computer other than atypical situations like what I demonstrated a year back.

A typical $10 USB cable made to appropriate specifications by a reputable brand is fine.

With that said, let's delve into this short "article" and consider truth and fiction (delusion?)...

HOWTO: Logitech Media Server + BrutefirDRC Plugin in Linux Virtual Machine (VM)

Looking back, early-January was a busy time for me! A number of work responsibilities and then I also had to deal with a computer issue - perhaps THE most annoying computer issue - hard drive failure on my server machine...

Of course important data was backed up so I didn't lose anything (I keep copies of important files in both my workstation computer in the upstairs office as well as the basement server). However, replacing hard drives remains an unfortunate and tiring affair of the modern day do-it-yourself tech user and computer audiophile. It turned out than a 2010 Western Digital 2TB WD20EARS "Caviar Green" was the cause of some file access slowdowns I was experiencing. I've since replaced the drive with a new 6TB Western Digital Red 6TB WD60EFRX. I believe these "Red" drives meant for NAS usage have reasonably good reputations for reliability.

Now the "good" thing about this otherwise unfortunate episode is that as I was tinkering with the server computer, I got to thinking more about the whole "keeping it simple" idea (I wrote about this idea late last year - of course that article was more about the whole concept of simplifying hi-res audio albums). But what about "keeping it simple" on the hardware side?

Over the past few years, I've done more with my computer in the listening room (as per my HTPC build articles - here and here). This has certainly allowed me to explore stuff like starting on the path down digital room correction (here and here), easily access my multichannel library through JRiver and HDMI to the receiver, and use my TEAC UD501 DAC for high-resolution and native DSD playback through USB. That's all of course on top of the video home theater tasks. But in fiddling with all this stuff, I found myself "missing" the simplicity of what I had done for years - just kicking back in the evenings in front of my sound system and streaming beautiful music off my good ol' Logitech Transporter machine which has been my main "go to" player for close to the last decade.

Greetings From Puerto Vallarta, Mexico...

Greetings from this place:

The Malecon at Puerto Vallarta...

Now, obviously, there's unlikely much in the way of audio equipment or audio discussion to engage in from here. However I wanted to show some pictures of what I have noticed in terms of hardware available at all the local electronics stores (dropped into a handful while shopping with the family, wandering the city)... A bit of a cultural experience for audio lovers I suppose.

HOWTO: Vinyl LP Cleaning with the 3M Bondo Locking Suction Cup Dent Pullers.

Time to clean some old Beatles - RIP George Martin...

Alright guys, I figured I'll post on something a bit less "heavy" and more fun for this week :-). (That's assuming one could consider LP cleaning as potentially fun rather than neurotic or obsessive...)

Although for the most part I listen to digital, I do still enjoy rummaging through the used vinyl at the local record shops. Great way to "get physical" with the music and great to sometimes pick up some minty LP's from the old days with sentimental value or some "classics" especially when the album cover artwork is in great shape.

As I posted a couple years back, I've got a little collection of "tools" for the LP set-up. For the most part, I still use the Spin Clean as my primary wet cleaning device. It's not too expensive, does the job well most of the time, and is quick and easy.

I had been curious about the various "record cleaning machines" as well and have tried an Okki Nokki here at home as well as had some records cleaned at the local record store using their VPI HW-16.5 (I think), and another one with a Music Hall WCS-2. I actually decided not to keep the Okki Nokki because I realized I just didn't "need" it for casual LP collecting... I found the vacuum too loud (in general I find this "audiophilically dysphoric"), didn't really want to deal with the liquid reservoir nor to devote tabletop space to something I wouldn't use enough of. Admittedly, I haven't tried the ultrasonic RCM devices so maybe those can work even better although they are significantly more expensive commercially, take up a bit of space, and one would still have to deal with the water bath.

MUSINGS: Cable Claims, Testimony ("Buyer's Guide") & Sponsored Content...

Cute CD BTW for the Simpsons lovers out there...

I must admit that I rarely pay attention to the folks at Hi-Fi+. Other than occasionally skim over an issue at the magazine stand, I find it generally lacking in details and looks too much like one big glossy advertisement.

Shortly after writing the previous article on Chromecast Audio including jitter discussions, I noticed on Dr. AIX's recent post that he linked to a 2015 "Hi-Fi+ Guide To Cables" PDF and decided to wander over for a peek (I know... Bad move, right?). I'm not going to enumerate all the disturbing comments and beliefs advocated but I would like to point the reader at the modestly interesting interviews with the various founders and representatives of the cable companies. Particularly, there was one question asked of each manufacturer - whether they would comment on the best type of digital connection to use: USB, I2S, Ethernet, or coaxial S/PDIF (why not include TosLink S/PDIF?).

MEASUREMENTS: Google Chromecast Audio - Part II: Digital Output

Chromecast Audio with optical TosLink adaptor & cable.

Alright, here's the follow-up to the Part I evaluation of the Chromecast Audio. Time now to have a look at the digital output using the mini-TosLink adaptor and standard TosLink digital optical out. Please refer to the previous post since I will be using the same settings and also the Plex Media Server system to run the tests today.

The first thing that needs to be addressed is whether the Chromecast Audio is capable of "bitperfect" output. Now, I do not have an easy way to capture the digital output, but one thing I can do is to make sure that a DTS signal encoded as 16/44 FLAC can be streamed from Plex to my digital receiver without audible issues... Indeed, in this regard the Chromecast succeeded.