HQPlayer's Network Audio Adapter

Miska:

Recently I read this quote and it reminded me that I would like to learn more about your embedded solution(s) and how it might be implemented. Instead of asking you directly via email, I thought I'd help bring this feature to the public eye at the same time. It would seem with the increased popularity of appliance based servers, others might be interested in learning as well. Please feel free to expound upon your ideas beyond my specific questions.

Do I understand it correctly that this is akin to mpd, but on steroids- pre processing the FLAC and upsampling and then via ethernet sending those files to an NAA?

Do you make such an NAA, or is it simply a Linux Ubuntu ALIX appliance or something that one builds themselves?

In purchasing a license for "embedded" does it include the rights to your Network Audio Daemon and the Desktop server, or does one need to purchase two licenses?

Does the Network Audio Daemon do multi channel too?

How do you suggest to go from ethernet>i2s?

From the Emm Labs DAC2x thread:

"I'm running multi-room system isolating the DSP processing and playback from the actual audio playback over ethernet and it works great for me. So an "ethernet DAC" solution, but still without even necessarily requiring a new DAC (something I call "NAA" for short). Alternatives vary from Ethernet in -> USB out to Ethernet in -> I2S out. And it is practically configuration-free. And works with DSD too. WLAN has been also working great. Good side is that this is in many cases still a separate box from a DAC and can run battery powered (for example 4x AA batteries).

Biggest problem I see with traditional network player (UPnP streamer) way is that the playback device is still dealing with all kind of complex things like decoding file formats and dealing with player functionality in general. Not just functioning as a DAC - doing much more than plain DAC would. If the device needs to deal with things like decoding a FLAC it is already doing too much."

Signalyst

Do I understand it correctly that this is akin to mpd, but on steroids- pre processing the FLAC and upsampling and then via ethernet sending those files to an NAA?

Yes, sort of. NAA is a way to expose remote audio devices to HQPlayer over asynchronous network link. It is just an audio "renderer" with support for number of different audio endpoint devices. Playback by NAA is completely clocked by the audio endpoint device and NAA performs only buffering, no decoding or processing at all. (A bit like asynchronous USB DAC, but having ethernet interface instead.) These endpoints are shown in the HQPlayer device selection just like local devices would, so you could have for example following kind of list:

livingroom: Mytek Stereo192-DSD DAC

livingroom: Musical Fidelity V-Link192

bedroom: Fostex HP-A8C

So in a local network there can be any number of NAA devices and each can have any number of audio endpoint devices.

All processing is performed by HQPlayer, either the Desktop-version which combines GUI and processing engine, or the Embedded-version which further splits the processing engine and GUI to separate entities.

Embedded version has a "headless" server process to perform all the actual file decoding and processing activities, it can play back audio to local devices or remotely to a NAA. For Embedded there's a separate touch-optimized remote control GUI that also operates over the network (can be run locally on the same machine too, nice for Win8 touch). Currently only Windows versions of these are downloadable, but Linux versions are possible too, just not offered due to low demand. I'm using both Windows and Linux versions myself.

Do you make such an NAA, or is it simply a Linux Ubuntu ALIX appliance or something that one builds themselves?

I'm not selling any hardware, not least due to EU regulatory overhead concerning direct electronics sales to consumers. One could also ask Demian/Auraliti or Jesus/Sonore for possibilities about having NAA on their devices.

Building a NAA device yourself is also an option, 32-bit x86 binary (deb) is offered for download. With ARM9 "armel" deb and Cortex-A8 "armhf" deb already in use here, and possibly coming available for download too. I also just got my Raspberry Pi and will be making a build for it too, just been a bit busy lately.

In purchasing a license for "embedded" does it include the rights to your Network Audio Daemon and the Desktop server, or does one need to purchase two licenses?

Any HQPlayer Desktop or Embedded license includes license to use any number of NAAs on your local network. Or to be exact, it's kind of vice versa, NAA EULA requires you to have a HQPlayer license.

Does the Network Audio Daemon do multi channel too?

Yes, up to 8 channels. DoP works too, up to 5.1 channels.

How do you suggest to go from ethernet>i2s?

Many of the SoC's (System-on-Chip) solutions have integrated I2S+I2C+SPI interfaces, so there are various ways how these can be utilized. Depending on particular hardware. So either interfacing to another box or directly to a DAC chip. But this is more hardcore, more for DIY hardware guys, or hardware companies (device manufacturers).

Thank you Miska!

Just some additional thoughts,

My point in the original posting was that a traditional "UPnP streamer" performs all kinds additional processing, like reading content from a mass storage, decoding a FLAC for example as well as commonly servicing a user interface too. So it practically becomes a single-purpose player computer.

Idea behind NAA is strip down as much as possible from the device that is connected to the DAC by keeping as much as possible behind the network in a player software. So NAA can become "whisper quiet" in terms of activity and also benefit from the isolation provided by Ethernet. And also isolate as much as possible at the software side by using a large asynchronous FIFO buffer. It also makes it easy to get high speed asynchronous optical isolation by using optical ethernet.

What I mean being quiet is also that it is possible to make a NAA run out of four AA batteries, or from a proper linear PSU. While not giving up any amount of processing at the player side.

One example photo:

NAA (ARM Cortex-A8 CPU) -> MuFi V-Link192 -> Mytek, playing back 192k PCM in this photo:

(this board could run the Embedded engine too...)

Miska:

At the risk of seeming silly, but can you make some specific device suggestions. The ARM device in the photo for starters, and maybe some bare bone computers. You mentioned a raspberry pi, and I assume a beagle board would work as well, but I do not know enough about any of them to dare just start. I think that I (and others) might be interested in some more turn key sort of options doable by novices such as myself. Maybe device suggestions and online compiled code (if required) for them. It would seem as if your approach may be the most stripped down low power solution out there presently that is capable of upsampling, DSP and multichannel. I think it would behoove you to help us exploit this capability more readily. Your IT prowess is evident, but I am an old audiophile that stumbled out of a vinyl cave only recently. I am willing and capable of small steps, but using Linux alone seems daunting in and of itself. Now that there are drivers for my M2Tech Evo, my interest is rekindled in this type of approach.

4est,

I posted elsewhere about how wonderful the Auraliti PK90USB was as an HQplayer NAA (default settings already onboard, etc). I will be selling mine, so if interested lemme know via PM.

4est,

I posted elsewhere about how wonderful the Auraliti PK90USB was as an HQplayer NAA (default settings already onboard, etc). I will be selling mine, so if interested lemme know via PM.

Thanks for the offer, I must have missed that posting Ted. Regardless, I had a PK90 here and was not as impressed as others. Due to lack of Evo drivers, I had to use a different USB>i2s device that sounded inferior to my hopped up Evo. I thought my Mini running XXHighend sounded comparable to it at the time. I might have hung in there longer sonically, but after 6 weeks of frustration and help from Demian and Raymond, I still could not get it to read my drive properly. I was missing half of my music files in an odd sort of way- <track 9 or >track 9 would not appear on a regular basis or even consistently. To add to that, I could still readily discern the difference between an AIFF and a WAV file and that was the clincher for me. I returned it and reluctantly swallowed the 15% restock fee. To this day, that same drive functions flawlessly in Mac and Windows with every player I know of.

4est, Sorry to hear that...but frankly was only referring to the PK90USb as using it to be your NAA (as per this thread). It is preconfigured to be an NAA.

4est:

I would like to duplicate your experience with aiff and wav. Can you point me to few tracks where you saw this issue? Also did the tracks start as wav and get converted to aiff or the other way? More details will allow me to duplicate the issue more precisely.

I'm sorry we couldn't resolve the issue with your source drive.

1audio:

No worries Demian, a roll of the dice! You especially were helpful at the time, but alas...

It has been about a year, and so I may be a bit foggy. As I recall, I put files on the USB stick I returned the device with a hard copy screen shot of the files on that stick. You had remote log in access at the time. I still have the hard drive unchanged and use it daily on Win7, but it started its life on Mac. The vast majority of the files were iTunes ALAC rips transcoded to AIFF by XLD with some WAVs that I didn't suspect would be read correctly.

I cannot even fault the Aurality directly as it seemed to vary with the client. The bare bones recommended one sort of worked on my iPod, but I have too much music to use that as my sole interface. Theremin and others exhibited the issues more.

Thanks. I'll badger Ray into preparing a USB stick with suitable material (I don't have a Mac).

The clients have been evolving as has the server (and my tweaking to get incompatible character sets to talk). Its still a problem to deal with all of the different variants on ASCII and older file systems with their limitations. Theremin seems to have been abandoned which is a shame.

At the risk of seeming silly, but can you make some specific device suggestions. The ARM device in the photo for starters, and maybe some bare bone computers. You mentioned a raspberry pi, and I assume a beagle board would work as well, but I do not know enough about any of them to dare just start. I think that I (and others) might be interested in some more turn key sort of options doable by novices such as myself.

No, not silly at all. I have just not yet decided what to specifically recommend. And since I have really limited technical support capacity I have to pick up only one thing that is easy enough if I start publicly offering something other than just a software component for DIY.

One option is to use some passive cooled Intel Atom, AMD Fusion or VIA Nano -based computers and install the provided binary package there. Ubuntu Server is a good starting point. Logic Supply sells bunch of different kind of suitable computers. Plus there are some companies selling VIA Artigo computers. I've sold a couple of pre-installed bootable USB memory sticks for these kind of computers.

The board in picture is BeagleBoard xM. I have also two BeagleBone boards, a Raspberry Pi (yet to find time to power it up) and Acme Systems FOX G20. (Note: USB on G20 is limited to 12 Mbps so 24/96)

Apart from plastic boxes for Raspberry Pi and FOX G20 I'm not aware of any ready-made casings for these, so it becomes more DIY and sourcing a good linear PSU requires some care.

I'll probably make ARM binary packages available sometime soon, when I get the same version of NAA software module built for all. Now the binaries I have are different versions I've built when I played with the particular hardware...

Thank you Miska!

I think in part, my (our) confusions come from not fully understanding the entire chain of control and processing and that gets further obfuscated by the amount of options in implementations. I hate to say this, but there may even be a market for something simple like a raspberry pi with a plastic case that outputs USB. The Squeezebox is phasing out, and there is a market for a networked USB. I noticed that Sonore has created an ethernet>SPDIF unit. Heck, make it work on 5v or 12v and there are plenty of LPSs and more to come.

I am sure that I am missing something, or just do not get the picture well enough to be of much help, and yet this very stripped down "digital buffer" sort of approach seems like the end goal of the CAPS or typical appliances one sees.

I hate to say this, but there may even be a market for something simple like a raspberry pi with a plastic case that outputs USB.

That's pretty much it... And zero-configuration (OK, you can give it a name through the player GUI). I still have to check what is the easy&optimal way to put it together and write some instructions for example here, needs a bit stripdown from the default OS. Audiophile-grade case for the Pi:

Pi Holder milled aluminum case for Raspberry Pi with logo ID: 1039 - $74.95 : Adafruit Industries, Unique & fun DIY electronics and kits

Found a casing for BeagleBone too (there seem to be some other too):

Adafruit Bone Box - Enclosure for Beagle Bone ID: 699 - $19.95 : Adafruit Industries, Unique & fun DIY electronics and kits

Heck, make it work on 5v or 12v and there are plenty of LPSs and more to come.

That's one reason I'm using these ARM-boards, they consume very little power, produce no heat in NAA use and run out of single 5V supply.

(and prices are tolerable)

Miska,

The NAA that my PK90USB provided was, of course, ethernet in, USB out. Since a goal of the possible hardware-based generic NAA is simplicity and uniformity (tech support would be minimal), what do you envision the digital output variations or options to be, if any? USB only? S/PDIF? Sorry if this was mentioned earlier..I read as much as I could but couldn't find it, but maybe it's obvious.

The Pi seems like a sweet little deal, a $75USD ethernet device that outputs USB, HDMI & can use your old Squeezebox power supply or batteries.

I am very curious about this and how it might sound- assuming that I can get my M2Tech drivers loaded on it.

The NAA that my PK90USB provided was, of course, ethernet in, USB out.

Yep, easy way to obtain a ready-made NAA with USB connectivity. Probably works on the other Auraliti variants too.

Since a goal of the possible hardware-based generic NAA is simplicity and uniformity (tech support would be minimal), what do you envision the digital output variations or options to be, if any? USB only? S/PDIF?

The ones currently in use are USB, SPDIF/AES and Firewire. Most popular at the moment is NAA with Firewire connection to a Mytek DAC. But of course there are good USB options too, like the Sonore/exD DAC.

Or you can build NAA straight into the DAC. Practically all ARM SoCs have I2S, I2C and SPI so it is possible to build a DAC with straight ethernet connection. Or have just an I2S output. (BeagleBoard and Raspberry Pi have a not-so-great DAC on-board)

These are the options I'm prototyping. Which one is best depends on the particular implementation and preferences... At least for me personally it is nice to be able to make almost any existing DAC network-connected with a tiny configuration-free box.

I've sold a couple of pre-installed bootable USB memory sticks for these kind of computers.

Both of my NAAs have been pre-installed bootable USB memory sticks that Miska has put together for me. I've literally just inserted the USB sticks into their respective PCs (one was originally a CAPSv1, the other originally a CAPSv2) and booted up. Absolutely no issues whatsoever, and a damn sight easier than installing a regular OS.

I'm very, very happy with the performance of HQPlayer->NAA->Mytek. I'd recommend this system to anyone interested in DSD playback (although PCM is very good also) at a reasonable cost.

Mani.

I2S- really? Is that on the pin headers, or do you tag it off the board? If there is a way to back clock it from the DAC (or an external clock), then sign me up!

Sheesh, where have I been! This seems like a great little project, even if it ends up as a secondary source for my family room or maybe even a HT streaming Netflix. IIRC, there are some neat little I2S DAC boards around...

I2S- really? Is that on the pin headers, or do you tag it off the board? If there is a way to back clock it from the DAC (or an external clock), then sign me up!

Usually it is on the headers, as well as I2C to control the DAC chip registers. Typically clocking can be also modified, depending on capabilities of the particular SoC.

To deal with the particular DAC chip and clocking configuration it needs a small custom ALSA audio driver. This adaptation is part of a BSP.

OK, just a quick update. Packages for the four different ARM-based boards are now online. One per each, support for more distros coming...

Index of /bins/arm

OK, that does it. I'll get on the list for a Pi. I've got a TP Buffalo III board that has just been sitting around, and an old Tera Dak 5v supply somewheres. Use a digital switch for i2s and I can put it side by side Lucien's WaveIO on the same bread board.

Cheap entertainment, thanks Miska!

Does the Rasp Pi package support i2s?

Does the Rasp Pi package support i2s?

I2S is at much lower level, there's an ALSA audio driver layer between the NAA software package and hardware.

I tested it with USB audio ALSA driver last night.