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Streaming music reception: implementation differentiation


In the more than a quarter century that I’ve been using and writing about tech devices forEDN(whether because I owned them or just temporarily got my hands on a review unit), a few stand out…in agoodway, mind you, versus any of the innumerable definition-and/or-implementation disasters that I’ve come across along the way. One of them isVoyetra Turtle Beach’s Audiotron, which Ifirst reviewed back in 2001, with coverage subsequently augmented bymultiple additional writeupsas the product’s feature set (and my ongoing use of it) evolved over the years. Here are a few images from my “raw materials” archive of that initial two-plus decades back writeup (thank goodness forhigh-capacity NASs!):

By modern standards, the Audiotron is charmingly archaic. That said, keep in mind that a prototype had been publicly demonstrated by company officials at the2000Microsoft Windows Hardware Engineering Conference, held thevery same year the Pandora Radio streaming music service launched(quick aside: Nolan Gasser’s tomeWhy You Like It: The Science and Culture of Music Tasteis a comprehensive and otherwise excellent read for anyone interested in the founding and evolution of Pandora, the Music Genome Project whose algorithms power the service and the theory underlying those algorithms). Those wereveryearly days for online (and more generally) digitally encoded audio, and the developers’ vision is all the more impressive when you consider its foreseeing and trendsetting outcome.

What was always most appealing to me about Audiotron was its self-contained functional nature, not to mention its rich implementation of the developers’ underlying vision. Solely by means of front panel buttons and a knob in combination with a monochrome display, you could both configure and operate the device to access music stored locally on anotherSMB-supportivenetworked device (such as a PC or NAS) as well as, less than a year later,tap into Internet-delivered audio streams(a feature set augmentation that also included web browser-based device access as a convenient adjunct to front-panel configuration and operation). Equally notably, you didn’t need to leverageUPnP AV/DLNAserver software running on that separate storage device to index your music library; Audiotron did the indexing all by itself.

Audiotron’s production ended in 2004, and ongoing support stopped three years later, leaving the device unable to (for example) support the more secure SMB protocols implemented by newer computer and NAS operating systems (with Audiotron rendered obsolete by those same operating systems’ in-parallel discard of support for the less secure SMB precursors), not to mention the lack of support for secure HTTP browser access. Ever since then, I’ve unsuccessfully searched for an encompassing Audiotron successor. Products I’ve purchased and used for varying amounts of time, all of which admittedly remain in long-term storage at my residence, include (in roughly chronological order):

They all undershot my aspirations to varying degrees, and for various reasons. For one thing, they all required UPnP server software (with which I’ve hadhit-and-miss success) in order to index music library content stored on a separate storage device…that is, if they supported LAN-housed content streaming at all. Before continuing, by the way, some if-necessary clarity: what I’mnotdiscussing here are Bluetooth-, WiFi- and/or wired devices that passively receive Ethernet packet-packaged streams initiated elsewhere and convert them to S/PDIF, HDMI and/or (if a DAC is included) analog audio for output to an A/V receiver, active or (if an amp is included) passive speakers, etc. What Iamdiscussing here, conversely, are products that are (oftenalso) more actively involved in the access process…displaying an index (whether generated locally or elsewhere) of LAN-housed music library content, enabling you to select what you want to listen to from that list and thenpullingthat content from wherever it exists on the LAN, and similarly enabling you to directly access content from various online services.

Roku phased out its music-centric products around 2008, when the company decided to focus its future efforts on online video services-supportive devices. Logitech got out of the networked audio receiver business six years afteracquiring it in 2006; although theLogitech Media Server(originally SlimServer) software is open-source and remains maintained, one of my two Squeezebox Booms now has adead display(and is on the teardown pile). And Grace Digital’s initial device generations, including mine, were rendered obsolete both by athird-party Internet radio search service shutdownand aSiriusXM access protocol upgrade.

I’ve more recently been trying out two different products that aspire to recreate (if not build on) my past Audiotron experiences, albeit with quite different implementations and therefore at least somewhat different outcomes. The one that comes closest to the Audiotron from an integrated hardware-and-software standpoint isBluesound’s NODE; a third-generation (intro’d in 2021) N130 black-color example currently inhabits my home office (it also comes in white):

The NODE N130, which Bluesound (asibling brand of NAD Electronics) refers to as a “Wireless Multi-Room Hi-Res Music Streamer”, runs the BluOS and is robustly featured. See for yourself:

  • Connect to any existing stereo amplifier, AV receiver, or powered audio system.
  • Powered by state of the art Quad-Core 1.8GHz ARM® Cortex™ A53 processor and a 32-bit/384khz premium DAC design.
  • HDMI eARC connectivity, digital, optical and analog input/output options, with wired and wireless headphone and subwoofer outputs.
  • Hi-res audio streaming with access to Internet radio stations, cloud music services, and your own local music library.
  • Dual band Wi-Fi, Gigabit Ethernet and support for 2-way Bluetooth aptX™ HD Bluetooth ensures music playback without interruption.
  • Create and control a seamless multi-room system with the intuitive BluOS Controller app [editor note: for Android and iOS].
  • Top panel touch controls with presets.
  • IR input and remote learning capability – Control it with the optional BluesoundRC1 Remote Controller.
  • Connect with the BluVoice skill in the Alexa app and useAmazon’s Alexavoice assistant to control Players around the home.
  • AirPlay 2 lets you play music or podcasts fromwireless stereo componentsthroughout your house — all in sync.

The NODE N130 is also positively reviewed; see the writeups atWhat Hi-Fi?andelsewherefor examples. That said, it’s also got a matching robust price tag: $599. And maybe I’ve just gotten burned by my abundant past experiences, both anecdotal and personal (and not necessarilysolely restricted to audio gear, either), but I always also get a bit twitchy whenever I consider a sole-sourced device. By means of analogy, one of Audiotron’s other shortcomings was that it didn’t support iTunes’ DRM. Sure, Apple laterturned its back on that, at least for downloadable content, but the company’s undoubtedly still “locking down” the streams that originate with its Apple Music subscription service, just as Microsoft, withits own Zune servicealong withPlaysForSure partnerssuch as Sandisk (Sansa) and Yahoo (Music Unlimited), had done in the past. Similarly, consider the earlier documented forced obsolescence of my Grace Digital streamer when SiriusXM changed its access protocol (and Grace Digital was for some unknown reason unable or unwilling to update its hardware accordingly). Bluesound (and NAD, plus PSB Speakers) parent company Lenbrook is established and sizeable, but nothing’s guaranteed in life; what happens if it is acquired, goes out of business or (like Logitech with the Squeezebox line or Roku with its SoundBridges) just decides to drop the products? Sooner or later, as withhome automation gear, the hardware will then turn into a paperweight for existing owners.

This all leads us to theotherproduct I’m currently reviewing, theAudiolab 6000N Play(mine’s black, as shown below; it also comes in silver):

The 6000N Play’s MSRP isalso$599, but I regularly see it on sale for $399 (as it is at bothMusic DirectandAudio Advisoras I write these words), and I bought mine brand new from an eBay retailer at a 15% discount ($339) fromthatpromo price. Operating under the assumption that the 6000N has a roughly comparable end-of-day functionality to its Bluesound competitor (it does) and that Audiolab is, like Bluesound, interested in turning a profit (it is), you might guess that there’s a fairly fundamental bill-of-materials cost implementation difference between the two products (there is). To understand how Audiolab’s engineers and software partner DTS pulled this fiscal trick, I’ll use an analogy from arecent teardown(bolded emphasis is mine):

Minimizing the total bill of materials (BOM) cost necessary to achieve target functionality is important for system developers in any technology sector. But in consumer electronics, this budget slimming can often be an ongoing corporate life-or-death exercise…One common way to reduce the device BOM is to offload as much of the total required processing, memory and other required resources to other connected devices. A “cloud” server is one common approach, but it has notable downsides that also beg for consideration from the device supplier and purchaser alike…

Another popular BOM-slimming approach involves leveraging a wired or (more commonly) wireless tethered local device with abundant processing, storage, imaging, and other resources, such as a smartphone or tablet.This technique has the convenient advantage of employing a device already in the consumer’s possession, which he or she has already paid for…

The notable requirement for the manufacturer here is that whatever device-offloading application is running on the tethered mobile device must comprehend all common mobile operating systems (predominantly Android and iOS, along with the related iPadOS for tablets, nowadays) and the various devices that run on them, and it must also evolve as both operating systems and hardware evolve. Otherwise, the application will sooner-or-later stop meaningfully working, as will the device it’s tethered to.

Just as with Chase’s $10 face-tracking smartphone stand, the 6000N Play offloads (at least initially) some of the total processing burden to a tethered smartphone. Look at the two products’ photos; neither the NODE nor the 6000N Play includes a front-panel display, but the NODE at least offers a limited-function top-panel touchscreen, along with a$59 optional remote control. And, although there’s no officially supported web browser interface for NODE, Bluesound-published APIs have enabled enthusiasts tocobble togethertheirown offerings.

Conversely, with the 6000N Play, there’s only a power switch on the front panel along with several user-configurable function buttons; primary configuration and control rely on thePlay-Fiapps for Android and iOS, along with a hobbled Windows offering. With Play-Fi, DTS has developed a maturestreaming ecosystemakin to, albeit more widely licensed than,Apple’s Airplay(formerlyAirTunes). Although the 6000N is conceptually similar to a fully standalone streaming receiver at a high level, the implementation differences result in some tradeoffs, which DTS hasslowly strived to surmount.

The 6000N Play, like Bluesound with its POWERNODE product variant, also comes in a more expensive amplifier-integrated version called the6000A Play, whose name hearkens to the standalone6000A amp; the6000 series familyeven includes amatching CD player. It dates from April 2019, here’s the intro video:

And here’s an overview of what setup and usage looked like back then:

Initial reviews of the device were mixed; the primary criticisms centered on a few key issues:

  • Hard-to-use software
  • Unreliable playback, especially when both the 6000N Play and its controlling mobile device were connected to the LAN via Wi-Fi (versus hardwired in the Audiolabs case)
  • An ongoing reliance on that mobile device’s “on” status to maintain playback, and
  • A dearth of gapless playback support

DTS’ Play-Fi software improvements may be incomplete but they’re still nothing to sneeze at. Re the second and third issues (unreliable playback and sustained mobile device reliance), at their common core was the fact that incoming music (whether LAN- or WAN-sourced) first streamed to the mobile device (smartphone or tablet) for initial processing, then streamed backoutof the mobile device, again over the LAN, to the 6000N Play. This redundancy not only effectively doubled the amount of packet traffic flowing over the LAN at any point in time, when both devices were on Wi-Fi it put a particular bandwidth and latency strain on the particularly fragile wireless span of that LAN. Not to mention the battery-draining and otherwise undesirable nature of the ongoing reliance on the mobile device, which likely had more important primary responsibilities…like taking and making phone calls!

DTS has decreased Play-Fi’s mobile device dependencies in several key aspects. First off, beginning with v5.2 of the software (I can’t find an official version history anywhere online, but I believe v5.2 dates from early 2020; keep in mind re my earlier “slowly” comment that Play-Fi wasoriginally introduced in 2012), DTS added support for DMR (DLNA’s Digital Media Renderer). Quoting fromDTS’ blog updateat the time:

This means that you’ll be able to use a DLNA Media Client or Player or stream directly to any product with DTS Play-Fi, without first needing the app. For example, you’ll be able to open BubbleUPnP [editor note: which I use], and tell it to render to your DTS Play-Fi product on the network, and your media server will play audio straight to your audio system, no app middle-man in-between.

More generally, beginning with Play-Fi v5, DTS added a new operating mode called “Transfer”:

After you start playback, you’ll see the new Transfer icon and button on the Zone and the Now Playing screen for any DTS Play-Fi product that can support this feature…Simply tap the button (or tap and hold on the album art while playing), and you’ll get a prompt to transfer to the Play-Fi product, freeing up your phone.

Transfer mode is more limiting in terms of your ability to control the Play-Fi peripheral from the mobile device, but it’s also definitely more freeing for that mobile device. Here’s an Android screenshot of playback in progress from the Amazon Music Unlimited service in normal mode:

and after the stream is transferred directly to the 6000N Play:

All of which leads us to the final issue, gapless playback, which is important enough that it justifies itsvery own Wikipedia entry:

Gapless playback is the uninterrupted playback of consecutive audio tracks, such that relative time distances in the original audio source are preserved over track boundaries on playback.

I listen to a lot of classical music, where a piece is often subdivided among multiple tracks albeit still intended to be heard seamlessly (i.e., with no inter-track pauses). I alsonot only occasionally capturebut much more frequently listen to a lot of live performance recordings; again, the artist’s and studio’s intent here is typically that playback through the sequence of tracks be interruption-free. Cue irony: historically,artificial inter-track gaps generated by Play-Fihad been reduced, albeit not fully eliminated, by means of use of the Transfer playback mode. That said, beginning with last fall’sPlay-Fi version 8.1, fully gapless playback isnow possible…but only innormalplayback mode. Transferred streams still have brief artificial gaps between tracks, although DTS’ documentation promises that a fix “will be coming with a future update, and we’ll have news to share on this soon.” I can’t wait.

By the way,audioXpresshas an excellent two-part “Improving Wireless Audio” series in itsNovember and December 2022 editionswhich I commend to your attention if you’d like to delve into this topic further. More generally, I recommend youspring for a subscription; it’s an excellent resource for engineers interested in all things audio, and I’m a long-time paid subscriber (to clarify that nobody incentivized me to say these nice words!).

Nearly 2,700 words. My poor associate editor colleague is going to kill me! I’ll sign off now and await your thoughts in the comments.

Brian Dipertis the Editor-in-Chief of the Edge AI and Vision Alliance, and a Senior Analyst at BDTI and Editor-in-Chief of InsideDSP, the company’s online newsletter.