INTERACT FORUM

I recently purchased a NAD D 7050 Integrated Amp with the intent of using it as a DLNA / AirPlay renderer. My Primary DLNA server is JRiver MC 20, this note (and thread) are about how to set everything up so it all works.

I have succeeded in making it work, but maybe not at its optimal, so I’ll detail it as much as I can and if anyone has feedback on how it might be improved, that would be great.

But first, a few words on why I chose this unit. The NAD D 7050 is one of the very first in a series of what are known as ‘Power DACs’, that is, an integrated amplifier where the DAC is the amplifier where the first time a signal becomes analog is in the output stages of the amp. Known also a Direct Drive Digital amps (and the moniker DDFA), this is fascinating tech, as it allows the amp to dynamically adjust for changes in load. I wanted to check this out, but didn’t want to spend the $6K a NAD M2 amp cost, so when the D 7050 recently dropped to $800, I was in and am now using it to power a 2.1 living room ‘background music’ system.

The sound quality of this unit is pretty amazing for the coin and the combination of features is just about right (with DLNA support excepted), with the subwoofer crossover being a favorite feature.  BTW- it is a stereo low-passed output on the analog out RCA jacks, so you’ll need a Y cable to combine them for a mono sub. Cut-off frequency is selectable (every 10hz from 40Hz to 200Hz) via the mobile app UI, pretty slick. The amp really works and punches well above its rated output.

Anyway, this is about getting network streaming working with this thing, so when I first installed it, I was easily able to AirPlay to it from my iPhone, so now I can share a podcast segment or some new music with others in the room. But my primary use was going to be driving content to it from MC via JRemote, something I’d been doing successfully to my Oppo 103 and to another AVR using the Audiophile 24bit option in the MC DLNA server. Since the D 7050 is a nice 24bit capable DAC (driven via USB from a PC, or via Coax/SPDIF), I assumed it would handle 24bit via DLNA. Well, you know what they say about assumptions. That did not work, just noise that told me the bit-depth/sample rate was off.

So now, I needed to figure out what the heck this thing actually supports in terms of DLNA, so thanks to some other threads here (https://yabb.jriver.com/interact/index.php?topic=92801.0) I found Whitebear’s (@AndrewFG) excellent renderer profiling tool http://www.whitebear.ch/dmra and used that to get the profile for the 7050.
Surprise! The DLNA implementation only supports 16bit and sample rates of 44 or 48Khz. Wow, how limited. But wait, it gets worse.
{edit: Correction, it claims that as 'for sure', but it actually supports 24/48 and 24/96, as now that the underying issue with the setNext bug is not interfering, I was able to test these. It transitions just fine between tracks of varying bit-depths and sample rates}

So after re-configuring the MC DLNA server (more details below) to output L16 / 44Khz fixed, I tested it with an album. First track plays just fine, sounds really good. It advances to the next and now it sounds horrible, all choppy. Go to next track and now it’s just that noise of wrong sample rate / bit depth thing again. WTF?

I can only conclude that there is an implementation bug in the DLNA rendering code of the 7050 and it defaults back to a sample rate of 48Khz for L16 sources when a new track comes in, as when I changed the forced output settings in the MC DLNA server to L16/48Khz it works flawlessly now.  {Edit: red-herring, it works with 44 as well as 48, see post #4}

So I now have achieved my goal, but it took some head-scratching and perseverance to get here, and I figured I’d share the journey and the results in case it helps others with this (and maybe other) NAD streamers.

Following are individual posts with the specifics for this streamer.