Open-source USB interface: Audio Widget

Changing capacitors

Hi guys!
I want to change some capacitors to improve sound quality, but want to make sure I've gotten everything right. There has been a board revision since Unixman gave a comment, so I want to make sure it still all applies to this board.
Unixman recommended: "See previous posts. Replace all of the 5 OsCon el. capacitors, plus add some of the "missing" (optional) ones: C15, C21, C31, C32, C33, C35 and C36/C37. "

I assume the 5 capacitors in red need to be replaced.
The ones marked in green are the optional ones that have been mentioned.
I could not find the optional 'C15'.
http://i.imgur.com/PBJGZXK.jpg
I'll go with the 6.3V silmic II, 220uF for all the 7 green and 5 red capacitors.
I'm also curious about changing out the capacitors marked in blue, but will leave this for another time. The RCA terminals will be changed too.

Whole board: http://i.imgur.com/uzBc0jD.jpg

By the way, the output resistors have been changed to Dale resistors (by a friend of mine) as you can see. :)
 
I haven't tested it yet myself, but seems like someone got raspyfi working on a BBB:

BeagleBone Black as an MPD server

I've been trying to get my BBB to work with the audio widget in uac2 mode. its not there yet (some periodic clicking every few seconds). when I use a uac1 spdif dongle (or the AW in uac1 mode) things are fine.

I'm using ubuntu on the BBB with latest updates.

I don't even use high res audio; just redbook audio and uac2 mode on the bone causes the regular clicking on left/right channels.

any hints on what could be tuned to get this to work properly?

(fwiw, files are on a nas over a wired network using nfs).
 
I got myself a hiface (vers 2) to try out for high res audio. on the beagle, its a lot better than the AW but still has some buffering or drop-out issues. not a regular clicking anymore but random drop-outs on 24/96 audio. on redbook or mp3 audio, things are fine.

it could just be that the beagle is underpowered or maybe the UAC2 code is not working well for the ARM cpu type.

so far, though, the BBB is not working out well for music playback. I have not tried my rasp-pi board but my understanding was that the BBB was the better designed system of the two ARM boards (and the pie has a known design flaw on its usb system which seems like a show-stopper).

it looks like I'll have to continue to use mini-itx systems for high quality music playback. the ARM little boards are not powerful enough (oddly, 1ghz; but the system, itself, does not even hold a candle to 'lowly atom cpus' on itx boards).
 
I just made an interesting observation. I've had my R-Pi running as a music player for quite some time now with the AB-1.2, playing music from both an NFS mount and spotify.

Spotify has worked great, but uncompressed files over NFS has been a bit problematic, with intermittent clicks and dropouts.

Today, just for convenience, I tried hooking it up over WIFI instead of LAN. Mosly because I only have one LAN cable routed to that part of my flat and I have an XBMC box there that also needs a connection. Anyways, I expected NFS playback to be completely unusable with WIFI. But to my surprise, it worked much better. It's much more responsive and there are no clicks or dropouts. :cheers:

I guess the WIFI connection has different buffer sizes compared to the wired interface, and that this is what makes the difference. I have however tried different buffer settings for the wired interface before (both larger and smaller), but it made no difference. So I can't say at this stage why WIFI works better.

So if you're having issues like the ones I had, try switching to WIFI. It might work.
 
Hmm. What Linux distro are you running on the Beaglebone, linuxworks? Just so I know to avoid that one. :)

I have the Audio Widget running pretty well on the Raspberry Pi. Haven't tried it on the BBB yet. The Pi developers have put a lot of effort into improving USB audio performance lately. I definitely recommend the latest kernel and firmware to give it a fair trial. I actually got better results with the new "FIQ fix" disabled.
 
I'm using the latest supported ubuntu on the beagle-black. installed to sd-card not to internal flash.

network is gig-e wired thru 2 switches and onto a dedicated NAS box (using 1 single drive in JBOD mode).

if I use my i3 system, no problems. using an atom n2800 board, still no problem. high res 24/96 audio works flawless on the hiFace and mostly flawless on the AW (slight metallic noises every so often, but its been this way for a long time now and its been months since I last did an upgrade).

strange that the wifi is working better for you. sounds backwards to me ;)

if I can locate my rpi board, I'll give that a try; but right now all I have are regular x86 pc's and the BBB board.

I'll try wifi when I get home today, on the BBB. but wired ethernet certainly should work better, not worse ;)
 
I'm using the latest supported ubuntu on the beagle-black. installed to sd-card not to internal flash.

network is gig-e wired thru 2 switches and onto a dedicated NAS box (using 1 single drive in JBOD mode).

if I use my i3 system, no problems. using an atom n2800 board, still no problem. high res 24/96 audio works flawless on the hiFace and mostly flawless on the AW (slight metallic noises every so often, but its been this way for a long time now and its been months since I last did an upgrade).

strange that the wifi is working better for you. sounds backwards to me ;)

if I can locate my rpi board, I'll give that a try; but right now all I have are regular x86 pc's and the BBB board.

I'll try wifi when I get home today, on the BBB. but wired ethernet certainly should work better, not worse ;)

Sounds backwards to me too, but I've been running wireless for two days now and not a single hitch. Maybe there's some bug in the LAN interface on the Pi. Either way, it works for me, so give it a try.
 
I want to change some capacitors to improve sound quality, but want to make sure I've gotten everything right. There has been a board revision since Unixman gave a comment, so I want to make sure it still all applies to this board.
it's not just a board revision... it's an almost completely different product, using a different DAC chip. Also the caps installed by default are of different types, thus my suggestions for the old version cannot be applied to AB1.2 (at least, not "as-is").

You may have a look for a discussion on the subject about AB1.2 here: "Async USB2 - SDR/Audio-Widget collaborative project".

See also here: "QNKTC AB1.2 – Dac e preamplificatore valvolare".

(both sites are Italian - try using an automatic translator...).
 
widget problem

hi guys, i have one small problem with widet, it seems to be working. flashing fimrmware was succesfull and after flashing is possible to fing widget in foobar and is possible play with widget but ..... when i disconnect widget from usb and after i connect it again widges is recognized as a AT32UC3 device in dev. manager is possible that fuses are wrong? i flashed 4 types of fw and it is the same situation..... all firmwares works but when i unplug dedget it is recognized as a AT32... not as a audio device :( please help me
 
just checking in to see the status of the firmware. is it considered 'done' now? is it free of all metallic sounds, at this point?
when it comes to software/firmware, 'done' would be a synonym for 'dead'. Quite the contrary: the project is alive and healthy. Firmware updates with improvements, bug fixes, etc are still coming out every now and then. :)

My old AB-1.1 have been (and is still) working flawlessly ever since for me, though some nice improvement have come with later versions of the firmware.

On some (other) system/software combinations some problems have been occasionally reported. AFAIK, all of the known problems should have been fixed by the latest release:

https://github.com/borgestrand/widget_binaries

https://github.com/borgestrand/widget_binaries/blob/master/audio-widget-20131208clean_RC.elf

 
Last edited:
There are few things on the functional todo list at the moment.

Adding DSD functionality has been discussed on the mailing list. I can help out, but I'd prefer to not be the guy who dives down deep into the AVR32 serial port and DMA code.

The revision numbering scheme could also improve. At the moment the firmware doesn't really know which version it is is. However, the .elf files are named quite clearly.


Børge
 
Adding DSD functionality has been discussed on the mailing list.
That would be me! :) It would really be a great feature to have, DSD over USB is all the rage now. The open standard for DSD over USB looks straightforward and ought to be easy to implement.
DoP open Standard | DSD-Guide.com

I can help out, but I'd prefer to not be the guy who dives down deep into the AVR32 serial port and DMA code.
So who would be the most familiar with that code to lend a hand?
 
Hello I have the qnktc for 1 year and a few months, no problems on macbook pro, i made some little improvements: used an external Psu with LT1763 regulator, silver usb cable. I am wondering if there is any chance to add a software volume control? (in system preferences it says that "The selected device has no output control". Sometimes I am listening music with Amarra, and navigate on web with safari and some pages have flash player with the volume set on high and it's annoying