in ,

Channel D PureMusic Playthrough w/ Qobuz, Spotify & Pandora

  • The big three. Computer audiophiles using Mac OS X will likely be familiar with the Channel D’s Pure Music, Sonic Studio’s Amarra and Audirvana+ – all alternatives to iTunes’ own playback engine. They each retain iTunes’ library management system but at the click of play digital audio is handed off to the third party player where lower system overheads and RAM pre-loading solicit an uptick in sound quality. Spend a few hours with any of these applications and you’ll find returning to iTunes running solo a most unsatisfactory listening experience: it will likely sound flat and lifeless in comparison. Whether it’s been a showroom demo or a home audition not once have I been unimpressed with the amelioration brought by each of these pieces of software.

    In 2014, we no longer consider only locally hosted libraries, accessed via an iTunes database. With Qobuz and WiMP lossless streaming services up and running we now look to the cloud as a source of music. Renting access to CD-quality music is big news. Spotify sates more (theoretical) casual listening via 320kbps Ogg Vorbis but it too can still sound downright impressive. Time to remind ourselves that the mastering quality is as (if not more) important than the delivery format.

    I recently detailed several ways in which to connect better software playback engines with Spotify and Qobuz. That coverage was somewhat Windows-centric with the final mention going to the forthcoming Amarra SQ, software that promises OS X users an audible improvement with ANY music application, not just iTunes. Ahead of its release I thought I’d take a closer look at its main competitor: Channel D’s PureMusic (US$129). I took the 15 day trial versions of 2.0.1 and 2.0.2 for a spin.

    Bundled inside the main app is the DPad plug-in which installs a virtual output device on your Mac through which any audio can be routed and – therefore – improved. DPad can also intercept audio played back from the web browser – hello Pandora radio.


    The Channel D website explains it thus: “Playthrough permits conveniently playing other computer audio sources (Internet radio, movies, etc.) through Pure Music, with full access to Pure Music’s dithered volume control, 64 bit crossover, audio EQ plug-ins, NetSend streaming, metering, etc.”

    DPad must be installed from within PureMusic’s audio setup options panel. Inside Playthrough’s software settings a hardware DAC can be specified. PureMusic must be restarted to apply any such changes. This brings us to my first niggle: decoupling PureMusic and iTunes just isn’t possible. The former launches the latter and you can expect to iTunes to remind you of its presence each time PureMusic starts up as well as each time it quits. This kinda bugs me but it isn’t a deal breaker. More troubling was PureMusic’s tendency to crash on exit upon which freshly applied settings were lost.

    An email to PureMusic’s tech support team on 14th June received no reply.

    Selecting Channel D DPad as the default output device in OS X’s system preferences and then engaging ‘Audio Playthrough’ (from PureMusic’s MusicServer drop down menu) is simple enough; signal metering shows the user when PureMusic is handling playback processing. With Pandora playing inside Google Chrome, A/B-ing between PM Playthrough and direct-to-DAC in OS X’s sound output device selection menu becomes a single-click affair. PureMusic definitely brings something to the party but with my headphone rig – LHLabs GeekOut firing into Audeze’s LCD-X – the gift is small. DPad routed audio is a smidge smoother, a soupçon softer…but that’s all she wrote.


    Without the ability to specify an audio output device from within Spotify’s desktop app it fires ones and zeroes at whichever hardware device is specified in OS X’s system preferences. Simple enough for everyday users but for power users looking to introduce third party engines like PureMusic’s DPad it comes up short. No way to tell Spotify that it’s gotta talk to DPad first. Instead, PureMusic hijacks the audio feed as per Pandora’s web browser audio stream. Investigating what PureMusic could do to lift Plastikman’s EX – which already sounds mighty fine in lossy format – was a short-lived affair. Engaging PureMusic Audio Playthrough introduced an occasional stream of glitching sounds to enter the playback chain of MacMini, Resonessence Labs Herus, REDGUM RGi60 and Zu Soul MKII. Disengaging Audio Playthrough was the only way to return to something listenable. Thinking the 2010 MacMini w/ 10.9.3 might not be powerful for the task I took to a 2011 MacBook Air w/ 10.9.3 only to be met with the same outcome. Imagine vinyl’s surface noise run through an IDM glitch plugin. Perhaps an even more powerful Mac was required? Without one to hand I’ll never know.

    An email to PureMusic’s software support service on 16th June was returned to sender marked ‘undeliverable’.

    Moving on

    Qobuz Hifi. Lossless streaming straight from France (or wherever their servers are located). Putting aside the discussions about artist remuneration for one monent, if anything’s going to kick CD sales into a distant niche it’s streaming services likes this: Redbook FLAC beamed straight to your desktop or smartphone for 20 Euros per month. You don’t own music, you rent access to a library of millions of songs. No, they don’t have everything imaginable. A search for Robyn Hitchcock turned up only four albums, of which only was available to my ‘UK’ region. With Australia not yet on the list of countries officially serviced by Qobuz, I’ve taken to what many an Australian does with Netflix: a $6/month subscription to the Unblock-us VPN service. A promo code provided by the Qobuz marketing team at the Munich High-end show kicked open the doors to a one month trial of their lossless streaming service.

    The Qobuz desktop application had me digging back twenty years for school-learned French but I think most people would pick “Préférences” as preferences. From there we’re able to access a drop down list of possible audio devices. In comes another gotcha! On the fly switching doesn’t work; a Qobuz app restart is required to engage a different device.


    After an hour or so of further futzing around, I discovered that Qobuz’s desktop app will output to whichever device it sees selected in OS X’s system preferences upon its launch. To hear a straight take via Resonessence Labs’ Herus requires explicit user selection of said device in the operating system’s sound options panel. For PureMusic to do its thing, Channel D PAD requires nomination as the system sound device. Only then will Qobuz’s audio be routed via the Channel D playback engine and onto whichever device is called out in PureMusic’s audio settings. Confused? You will be! Another time-consuming trial and error session revealed that one must launch PureMusic before firing up Qobuz, after which Audio Playthrough is easily engaged from the ‘MusicServer’ dropdown. If in doubt, look for the tick of confirmation. I needed to disengage and engage a second time to banish the “Ready…Select Track and press Play” scrolling marquee from PureMusic’s elongated floating window.

    What does Qobuz + PureMusic sound like? The short answer is: I’ve no idea. On both Apple Macs I encountered the same glitched-static discharge as with Spotify playback. Bummer. Switching from the Herus to the PS Audio Direct Stream DAC didn’t help. Neither did checking the box that hands over volume control to the hardware. No dice when enabling ‘Hog mode’ either. The lesson learnt? Not all reviews end on happy terms – some are are a stumble followed by a fall. For this user, on this day, with this equipment, PureMusic 2.0.2’s Playthrough is a miss.

    Further information: Channel D

    PS. If you’ve experienced better results with Pure Music’s DPad/Playthrough please hit up the comments section below.

    John Darko

    Written by John Darko

    John currently lives in Berlin where creates videos and podcasts and pens written pieces for Darko.Audio. He has also contributed to 6moons, TONEAudio, AudioStream and Stereophile.

    Darko.Audio is a member of EISA.

    Follow John on YouTube or Instagram


    1. For me D-Pad Playthrough for Qobuz works without a hitch. You might want to ping Channel D’s Rob Robinson who can remote-connect to your computer and resolve the issue. If he can’t (hard to believe), he’ll learn something and write a new update for PureMusic 2.0.3 that’ll take care of it -:)

      • Two attempts at contacting them came to nothing: one email received no reply, the other returned to sender marked ‘undeliverable’. But, I *shall* try again with a view to a follow-up piece.

    2. Just heard back from Rob. He never got any of your emails so presumably the one you used was faulty; or some other computer weirdness interfered. Anyhow, now that he knows of your issue, I’d be surprised if it didn’t get sorted quickly and who knows… like me you might find that Playthrough + Qobuz does work very nicely indeed -:)

    3. Having previously raised the issue of poor stability with version 2.0.1 with Rob Robinson I emailed him to say 2.0.2 had not improved things. This was his reply
      “Thanks for the information. The 2.0.2 update was not meant to address this Playthrough issue, but other things. (It actually takes quite some time for issue fixes to work their way through testing to the final release, and the changes in 2.0.2 were already much further along in the process.) The complete list of changes made in an update are given in the Change History of the Pure Music 2 User’s Guide included with the software downloaded (and is updated for each new version). It is an exhaustive list, so only items specifically changed in the software are listed there. Playthrough performance has the highest priority for us now, and thank you for your patience while we work on addressing this.”
      I found this useful and thought it constituted good customer service

      • Yes, a third email to Channel D finally arrived AOK and Rob’s been in touch. (Thanks Srajan!) He is now aware of at least one of the problems I’ve experienced with his email system.

        Am looking forward to chatting with Rob about Playthrough stability but as you point out Andy, it looks like he’s already across it. In a perverse way, it’s reassuring to know I’m not alone with minor Playthrough performance issues – what version of OS X are you (guys) using?

    4. Hi, Rob Robinson from Channel D here.

      John, I received your reply but thought it might be more useful to post this here. I wanted to begin by saying that we never received an email from you around June 14. Perhaps it was misaddressed? (Sometimes folks type instead of The last previous email we received from you was on March 25, 2013, pertaining to an article you had written about (mostly) unsatisfactory performance of gapless playback in two music player applications. Pure Music wasn’t mentioned in that piece, but in your email you said you were considering a follow up covering Pure Music’s gapless playback. We never heard anything after that.

      Obviously, we didn’t receive the June 16 email either (bounce message). For about the past month we been having a problem with our email server being letterbombed on weekends, when staff is away, filling our mailbox. Your June 16 email would have arrived here on June 15 (Sunday) – June 15 in the States being June 16 in Australia – when our emails aren’t monitored. However, that mailbox problem has since been dealt with.

      Even under ideal conditions email isn’t always 100% reliable. However, and fortunately, we are one of a few audio player software companies that actually posts a telephone number for tech support. Just as a suggestion, there is a large time difference, but a short message even at 3 AM local time alerting us to the effect that your email wasn’t answered would have helped, and we could have taken it from there. With all due respect, I think it behooves a reviewer encountering difficulty with a product to “go the extra kilometer” in trying to contact the manufacturer, especially when the manufacturer is unaware that a review is in progress. We only found out about this article yesterday. I hope that should we find ourselves in this situation again, some two-way communication before the publishing step would be very much appreciated…

      Anyway, regarding the issue you are encountering. Obviously it is not endemic, as Srajan Ebaen (evidenced from his posts), other reviewers, and the majority of our users aren’t having any trouble with Playthrough. A certain number of users with certain computer + DAC configurations are experiencing the same issue that you are, or in some cases worse (unexpected quit). This is covered on our website Support page for Pure Music (under the topic “Pure Music 2 – unexpected quit with Playthrough:”

      “We have made changes to Playthrough in Pure Music 2 that have benefited users having synchronization issues with the Playthrough in previous versions (caused intermittent clicks or drop-outs in the audio). However we have received a few reports regarding Pure Music 2 Playthrough stability from users who experienced no playback issues before, and are looking into this.”

      “If Playthrough is required, and provided Playthrough worked satisfactorily in the previous version of Pure Music (without intermittent clicks in the audio) a short term work-around is to use the previous Pure Music 1.89g R3 for Playthrough functionality and switch to Pure Music 2 for other audio playback. We are investigating the issue. “

      In addition, Andy Duncan (in his post above) copied my email that amplifies on the above. The bottom line is that anyone interested in this feature can try our free Demo which runs for 15 days (and does not require registration or an Internet connection to run it). The playthrough feature will either work perfectly (which is typical) or not (in certain situations). In the latter case we would invite such users to try again once we have performed further fine-tuning in a forthcoming free update (again, noting that we have made significant changes to Playthrough in the Pure Music 2 release).

      My suggestion before trying the Playthrough feature, should trouble arise, is to shut down (not restart) the computer, power cycle (off – on) the DAC (or disconnect the data cable, if powered over the data bus), then restart. If running OS X 8 or OS X 9, be sure to disallow “reopening windows” when shutting down, and after restart *only* launch Pure Music (which will automatically launch iTunes). If you like, Hide iTunes, and next launch Qobuz, Spotify, etc. The reason for the shutdown operation is that this restores low-level audio properties on the system that are sometimes reset by other players, and not properly restored when they quit. This can be detrimental to the performance of Pure Music (and especially can rear its head in an A/B comparison situation).

      Incidentally, though I reckon the above article came about because of a news release from another company promoting a similar, “new” feature in their product, I think it’s worth noting that Pure Music has already had the “Playthrough” streaming audio feature for well over 3 years. In addition, it doesn’t require quitting Pure Music to use the streaming feature, nor does it require a separate application, as does the other product. Furthermore, if playing iTunes Internet Radio, music samples in the iTunes store, or protected AAC tracks, switchover is automatic. For other sources, it is just a matter of selecting a menu command, as you observed. Automatic switchover to streaming mode will be added for all streaming sources in a future update.

      I apologize in advance if this post has become a little too long. Thank you very much for your time, and kind consideration.


      Rob Robinson

      Channel D

      • Hi Rob

        Thanks for the extensive reply – appreciated.

        You are correct, my interest in PlayThrough stemmed from both a comment from Srajan Ebaen about its existence as well as the imminent release of Amarra sQ. I called out the latter in the article’s introduction.

        I take your point that the issues I’ve experienced with Playthrough aren’t necessarily endemic but given multiple attempts with TWO Macs and a whole plethora of DACs (a list that stretched beyond those called out in the article) it seemed to me that these technical issues could not necessarily be described as ‘isolated’. The random crashing on quit when applying settings added another niggle to the mix. It too presented on both Macs.

        Negotiating time differences and (therefore) a personal preference for email communication combined with my presently conducting review work on weekends (due to day job commitments) all fed into my not picking up the phone. Trying to thread time for review coverage in and around a day job, one does most of the bill-paying, is often the reason why follow-up pieces (like the one on gapless that you mention) don’t always come to fruition. Besides, given that gapless playback is still not a given on many devices, I didn’t want to find myself penning yet another whinge. Please let me/us know if PureMusic handles iTunes library playback gaplessly.

        Neither the Playthrough glitching nor the email silence were necessarily troublesome in their own right…but when combined, they didn’t sum to too flattering a picture of my experiences with Channel D. Given your current issues with your email server it seems more probable that my first email went down the gurgler somewhere. I’m 99% confident that I typed the address correctly.

        However – I’m not too egotistical to see how I might have erred in this process and, on reflection, I should’ve perhaps picked up the phone. Something that I intend to correct this week. Let’s see if we can move this forward *together*. 🙂

    5. Hi John – that works for me. Maybe we can schedule a Remote Session, and have a look, also. (Note – Friday July 4 is the national Independence Day holiday here, and our office will be closed.) Prominent on the development docket is resolving these issues with Playthrough. I agree it is odd that you had trouble with two different machines, particularly if you tried my suggestion of a shutdown with only launching Pure Music afterwards? But it definitely will be resolved. On the other point, gapless playback is automatic in Pure Music and uses the iTunes UI, no need to designate tracks / albums for “preloading” nor is it limited to only uncompressed track formats. The only current limitation is gapless playback of DSD is not yet enabled, and this is also a focus of attention here. Cheers – Rob

    6. I have had he same issue with playthrough mode. It simply does not work. It locks up and Pure Music quits. I keep checking back to your review to see if you had any success. Looks like three weeks have gone by and no software updates.

      • Hey Walt – Rob Robinson and I have been in touch. He stayed back late (his time) to remote connect to my MacMini to see what was up. A software update with a fix for the ‘glitching’ sounds was forthcoming from Rob over the weekend and I’ll be trying it out tomorrow. Hang tight. An update on this IS coming.

        • Hi John – Any update on the play through issue with Pure Music? Their site stills lists the following:
          UPDATE (July 15, 2014) – We’ve identified the cause of the issue and have a test version of Pure Music 2 in the hands of users who have reported this issue. So far, the reports have been positive. We will be posting a free Pure Music 2 update as soon as we have completed further testing and finalized the changes.

          • Hey Walt – I tried the 203d2 update and it removed some (but not all) of the crackling/distortion sounds. I re-installed the MacBook Air’s OS back to stock Snow Leopard but still the issue presented. A bit frustrating really. I suspect I might need a higher-powered machine but that won’t happen until funds allow. So PureMusic’s currently on the back burner whilst I work through other reviews and news items. I’ll be meeting with Rob Robinson when I visit NJ in September so perhaps he and I will be able to nut out possible causes (and him solutions) then.

    7. On 8 August I replied as below to Rob Robinson who asked whether the update (now called Streamthrough) was working satisfactorily. As you can see my experience is similar to yours.
      Hello Rob
      I wouldn’t go as far as to say satisfactorily, whilst File Player is an excellent addition to iTunes and I am very happy with that purchase, I do find Streamthrough somewhat frustrating in that it cannot be relied upon yet, as soon as I think it’s playing really well, something happens, like the incidents I have mentioned in testing it. The clicks and scratching noises continue to happen at random no matter what precautions are taken.
      I believe the sound quality improvements achieved by Streamthrough are substantial and worth continuing to be worked on so that hopefully in time it will work as well as File Player.
      I appreciate being given the opportunity to test your product. Please do not hesitate to contact me again if you wish me to test out any future products.
      Kind regards

      • I’m with you Andy – the benefits of Streamthrough are there but the sporadic issues with clicks/scratching mean I can’t yet recommend it to others. Rob tells me these issues are only affecting a small minority of users – I wonder: what are the specs of your Mac?

        I’ve had little luck with both a 2011 MacBook Air (Mountain Lion and Snow Leopard) and a 2010 MacMini (Mountain Lion).

        • Hi John,
          I am using as late model year 2012 mac mini 2.3 Ghz Intel i7 with OSX10.9.4 and 8GB of RAM The computer’s only purpose is to operate as a music server. It is connected to a PS Audio NuWave DAC.

          • And you’re getting the crackling distortion with Streamthrough/Playthrough mode on that machine?

            • Hi John- I used to get crackling noise with the previous version. It occurred during transition from one song to the next. I can’t tell if version 2 does this since it freezes after streaming for 2-3 minutes. I never get through a song and I have to force quit the software each time.

    8. Hello John
      I’m currently using a 2011 iMac OS X Lion 10.7.5. I wonder if newer machines / operating systems experience the same problems? It would be intersting to know if all of the “small minority of users” have older models.

      • I’ve not been able to sidestep the issues on two different machines running Mavericks and one running Snow Leopard so it might not be related to the vintage of the OS X.

    Resonessence Labs INVICTA Mirus review

    PS Audio Sprout – a Q&A with Scott McGowan