UPNP controllers and best design solution?

[davide256]

Its been made apparent to me in my own testing over the last 10 days that not all controller solutions are created equal. I've tried the following listed in descending order of fidelity, with an Oppo-103 (dec2013 rev level) as renderer, PC running minimal Server 2012 install with Foobar2000 as media server (which I prefer for better bass, detail than Minimserver, Asset, JRiver)

 

1. Oppo as controller using its remote - no eye candy, but more palpable "you are there" experience

2. Kinsky on android mobile as controller- can be quirky to get started and with Foobar2000 I have some advance to next track failures but comes closest to controlling directly via the Oppo and no transcoding glitches

3 Bubble UPnP - works reliably but unpredictable what bit depth, bandwidth rate gets sent to the renderer with Foobar2000. Very frustrating to have a high rez file streamed as lower rez.

 

These were the free to download versions but did not see any limitations listed that affected fidelity.

 

All files wav or lossless flac

 

So obviously some digging into Foobar2000 required to minimize the quirks but wanted to pose a question to fellow DLNA dabblers at CA.

 

It seems to me that in good controller design, that the only interaction between the controller and the renderer should be that of list push/pop and track start/stop/pause/seek (ignoring volume). Why do I hear a degradation using android mobile phone as controller that implies an ongoing added processor load on the renderer?

 

I'd really like to use a software remote but not at the expense of fidelity.

[Cebolla]

The BubbleUPnP Android app should not normally be involved in any transcoding when used as a control point. I suspect you are possibly using it in combination with the BubbleUPnP Server application (running on the pc). The BubbleUPnP Server is not required for standard UPnP/DLNA streaming (with or without the BubbleUPnP Android app, despite their shared name).

 

Are you running the BubbleUPnP Server? If so, stop using it altogether or switch off the "Transcode hi-res audio to 44.1/16 or 48/16 FLAC" settings on it (in Settings > Advanced).

 

 

 

It seems to me that in good controller design, that the only interaction between the controller and the renderer should be that of list push/pop and track start/stop/pause/seek (ignoring volume). Why do I hear a degradation using android mobile phone as controller that implies an ongoing added processor load on the renderer?

No idea, as it should not be possible for the control point to be involved in the player's process of producing the audio signal that gets sent to the DAC. Is it possible that the 'degradation' you are hearing is some sort of interruption to the renderer's playback process itself, due to its own poor design of not being able to cope with an unexepected or unsupported communication from the control point?

[davide256]

Cebolla, I'd forgotten I enabled Bubble UPNP on the server when I was playing around, will retry Bubble

as controller app with Bubble turned off on the server.

 

So I think we both agree that in theory the controller should be doing event driven transactions. Which then raises the question of what impact does the renderer UPNP "listener" agent for those events have on performance. Its entirely possible that the Oppo 103 lacks CPU horsepower or has an inefficient listener firmware for use of software remote vs a hardware remote control..

[Cebolla]

Indeed, though I've no experience in the actual UPnP mechanism, so as you can only speculate. I believe the implementation is via a set of UPnP function calls, presumably with callbacks to be used as event handlers or similar.

 

It's entirely possible that there is no efficient way of handling 'events', within the Oppo's embedded operating system and it may be resorting to some inefficient form of 'listening', such as polling. However, given the sophistication of current systems, it's not very likely. What's more possible is lack of resources due to some oversight in the original design and/or even poor implementation practices.