Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Digital Source Digital Players and Recorders: CD , SACD , Tape, Memory Card, etc.

Open-source USB interface: Audio Widget
Open-source USB interface: Audio Widget
Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 31st December 2011, 09:22 PM   #781
1audio is offline 1audio  United States
diyAudio Member
 
Join Date: Mar 2004
Location: SF Bay Area
Open-source USB interface: Audio Widget
Default JTest

You can get good comparitive measurements on JTest in Stereophile reviews. The settings to match their measurements are 131K points, 44.1 KHz sample rate and 100 averages.

There is some info and software here クロックのジッターの測定方法その3 The Google translation isn't too bad. I passed my measurements to Borge to post.
__________________
Demian Martin
Product Design Services
  Reply With Quote
Old 31st December 2011, 10:57 PM   #782
rsdio is offline rsdio  United States
diyAudio Member
 
Join Date: Feb 2008
Location: Seattle
Quote:
Originally Posted by borges View Post
None of the listed modes are 32-bit. My guess is that the driver has a few modes compiled in, and simply zero-pads up to 32 bits.
"32-bit" is too vague. It's best to specify whether this means 32-bit float or 32-bit fixed integer. It would also be handy to say whether this refers to the USB data path or the I2S bit stream.

Most "32-bit" audio systems are 32-bit float, which is basically the same as 24-bit fixed point in terms of significant bits. I have not seen data sheets for the so-called 32-bit DAC chips, so it would be important to know whether they support float or fixed-point.

By the way, 24-bit samples have over 144 dB of dynamic range, which is enough to span from the absolute minimum sound pressure at the threshold of human hearing all the way to the pressure within a short range of a nuclear explosion. If you happen to think that 24-bit audio is insufficient, then you're overestimating your ability to piece together a sound system that could perform beyond the 24-bit range.
  Reply With Quote
Old 31st December 2011, 11:26 PM   #783
alexlee188 is offline alexlee188  Canada
diyAudio Member
 
Join Date: Apr 2011
"32bit" DAC, see, for example,

Audio Converter - Audio DAC - PCM5102 - TI.com

32 bit refers to the PCM data, so it is a signed 32 bit integer.

Giving full 32 bit i2S samples to the DAC may have advantages which are NOT directly related to whether the human ear can hear over 144dB of dynamic range or whether we can put together a sound system to playback > 144 dB dynamic range :-)

It has more to do with the internal processing that the DAC does to the incoming I2S data - and there is much DSP processing that is going on in the chips that we are interested in :-) With 32 bit of input data, the processing can be more accurate so hopefully the final output to the sigma delta engine is more refined.

This is, of course, our conjecture at the moment as we have not played with a "real" 32 bit DAC yet. So when we have an AB with ES9018 we will find out :-)

Alex
  Reply With Quote
Old 1st January 2012, 09:23 AM   #784
UnixMan is offline UnixMan  Italy
diyAudio Member
 
UnixMan's Avatar
 
Join Date: Apr 2005
Location: L'Aquila, Italy
Quote:
Originally Posted by sampler View Post
That's exactly my thoughts too, but from lack of responses it's seems no one has tried that yet. Theoretically this sounds doable and would enable at least some uac2 support for higher sample rates without hacking 3d parity drivers of other vendors. Borges, UnixMan, anyone ?
It may be doable, but... sorry, I don't quite see the point of doing something like that!

It would only allow to run MPD in a sub-optimal environment, likely with degraded SQ. What would be the advantages WRT running "Voyage MPD" natively on a separate, dedicated hardware and controlling it from a client such as "gmpc" running on windows?

You don't need an expensive, powerful, full-featured PC to run MPD. All that you need is a small, cheap SBC such as the "Voyage MPD Starter Kit" (see how small it is!) or just about any old, no longer used PC/laptop/netbook you may already have. As far as it have a working USB2 socket, it may be used.

Any native solution will work (and sound) much better than any windows-hosted emulated environment on the latest, greatest and most expensive hardware... and would be even easier to set-up than an emulated system.

BTW: Happy New Year!
__________________
Quote:
"We should no more let numbers define audio quality than we would let chemical analysis be the arbiter of fine wines." N.P.

Last edited by UnixMan; 1st January 2012 at 09:49 AM.
  Reply With Quote
Old 1st January 2012, 09:37 AM   #785
UnixMan is offline UnixMan  Italy
diyAudio Member
 
UnixMan's Avatar
 
Join Date: Apr 2005
Location: L'Aquila, Italy
Quote:
Originally Posted by alexlee188 View Post
So when we have an AB with ES9018 we will find out :-)
that's what I'd love to see... two of them please, in a fully dual-mono configuration!
__________________
Quote:
"We should no more let numbers define audio quality than we would let chemical analysis be the arbiter of fine wines." N.P.
  Reply With Quote
Old 1st January 2012, 11:50 AM   #786
sampler is offline sampler  Lithuania
diyAudio Member
 
Join Date: Jan 2010
Quote:
Originally Posted by UnixMan View Post
It may be doable, but... sorry, I don't quite see the point of doing something like that!
UnixMan, I'm all with you on this one and are well aware of all the "backwardness" of such sub-optimal setup (see my ps in first post), but the whole idea behind this was to give user's that are somehow handicapped to ms os'es (like me for instance, as my job software is not multi platform) a chance to have temporally solution for full wrt usage. By all means I'm not implying that it would be on pair with native win uac2 driver, but let's be a little bit pragmatic here shall we ? It's not coming along any time soon...
And yes, any stand alone embedded/pc/laptop solution would be better if that's the way you want to go.

Quote:
Originally Posted by borges View Post
- Which VMs are available with sensible licenses?
- Will a VM forward a raw USB port not supported by the host OS?
I would say Virtual Box (GPLv2) with Oracle VM VirtualBox Extension for USB2.0 support (PUEL), so it's free. I'll have to do more digging on how ports are forwarded to guest os'es. From 5min. googling it seems that people are having troubles with streaming devices with this setup, so probably it's not raw mounting. I don't have wrt module (yet) to test this setup, maybe someone is willing to give it a tray ?

Happy and productive new year to all of you guys
  Reply With Quote
Old 1st January 2012, 01:42 PM   #787
cyteen is offline cyteen  England
diyAudio Member
 
cyteen's Avatar
 
Join Date: Mar 2004
Location: S.E
Quote:
Originally Posted by sampler View Post
but let's be a little bit pragmatic here shall we ? It's not coming along any time soon...
I don't think the word pragmatic means what you thinks it does. Bringing into line ones philosophy with observed reality rather than founding it on philosophical ideals. The observed reality is that a platforms other than windows does support UAC2 and by your own statement that is likely to remain true for some time.

At this point I think you would be better off putting your work software in a virtualbox hosted on a unix based OS although mixing work and non work on the same machine is asking for trouble.
  Reply With Quote
Old 1st January 2012, 02:58 PM   #788
sampler is offline sampler  Lithuania
diyAudio Member
 
Join Date: Jan 2010
Quote:
Originally Posted by cyteen View Post
I don't think the word pragmatic means what you thinks it does.
No philosophical background was intended, as it is common adjective synonym for practical, realistic, down-to-earth... But I get your point.
  Reply With Quote
Old 1st January 2012, 03:15 PM   #789
borges is offline borges  Norway
diyAudio Member
 
Join Date: Dec 2003
Location: Oslo, Norway
A lot of people are stuck with MS equipment. UAC2 audio will only gain wide popularity once it works well on Windows.

To make it work we can wait for an MS driver to appear. That won't happen before your grandsons grow beards. Or we can give a pile of cash to Thesycon or similar, or we can write it ourselves. Now, an open source project usually needs someone to contribute the initial 10k lines of code. That will not happen here. None of us has the Windows USB knowledge required. And those who come closed are scares witless from the size of the tastk.

So instead of wrapping our brains around it, the thought is to wrap CPU cycles around it. I fully agree that it is better to set up some dedicated hardware or indeed boot an OS which simply works.

But those two are already in place. A general solution for supporting Microsoft's left-overs through a lightweight linux kernel is actually quite entertaining to me :-)

Have you seen the Cooperative Linux project at Cooperative Linux | Free software downloads at SourceForge.net ?

Brge
  Reply With Quote
Old 1st January 2012, 06:24 PM   #790
borges is offline borges  Norway
diyAudio Member
 
Join Date: Dec 2003
Location: Oslo, Norway
Default Linux player setup

Sorry for needing some hand-holding here... I followed your instruction, and "Sound" under "System Settings" went empty. I more or less expected that with PulseAudio gone. Couldn't find a configuration menu in Banshee. Tried Alt-F2, "gstreamer-properties". That let me select ALSA, and the test tones worked. But Banshee remains mute.

I'm using Linux Mint at the moment. Not stuck to that at all, but I can't work with Ubuntu's latest GUI.

Any suggestions?

I haven't used Linux in quite some years. Used to compile my own kernels before v2.0, but in the meantime work and hobbies have dictated use of Windows due to SW compatibility. I'm willing to try things out. I (and other explorers stuck on Windows with me) would love a Linux live CD which booted right into a player. No passwords, logins, configs, just a bit-correct player.

I'll try Voyage too. But that also seemed like quite a few command lines to get it installed and working.


Brge

Quote:
Originally Posted by UnixMan View Post
In Linux, the simple and definitive solution is to get rid of pulseaudio. Just unistall it:

Code:
apt-get purge pulseaudio
and instruct whatever player you like to directly use ALSA instead.
.
  Reply With Quote

Reply


Open-source USB interface: Audio WidgetHide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Async 192Khz USB - the SDR-Widget collaborative project SunRa PC Based 5 26th April 2011 06:38 PM
usb audio interface david12 Equipment & Tools 14 10th October 2010 02:58 AM
Cheap Audio Interface (USB?) to PC agm2003 Instruments and Amps 11 16th September 2007 07:48 AM
Open call for suggestions on Open Source DIY Audio Design gfergy Everything Else 1 15th April 2007 07:33 AM
USB Interface Perfect?- Computer Audio fmak Digital Source 3 4th December 2004 10:24 PM


New To Site? Need Help?

All times are GMT. The time now is 02:28 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki