Well, here is a lengthy technical post about how to do ASIO with the E-mu 0404 USB 2.0. It took me awhile to figure it out, so I though that I would share.
(Disregard references to a conversation from a post in another forum.)
First, though, to answer your question about 24/96 and 24/192 flac file sources, I have good news and bad news. The good news is that there is plenty of material available from 4-5 sources or more. The bad news (possibly) is that most of the tracks are classical, jazz, and unknown individual artists; certainly not the latest and greatest popular music. The reason is that, in light of file-sharing technology, the large music producers are understandably paranoid about releasing master-quality tracks potentially worth millions of dollars each. In fact, they not even very happy about the lack of protection associated with redbook CD-quality tracks at 16/44.1 kHz. But when the redbook technology was introduced, neither the inexpensive ripping tools nor the copy protection technologies were available. So, to make a long story short, the producers are meeting consumer demand for higher-quality tracks with SACDs, whose encryption is associated with each copy of the optical media itself. The problem with this, of course, is that no "fair use" (such as playing a purchased track on a computer-based sound system or in an HD player) is possible. But I digress. Here is a list of HD source websites:
Linn Records
MusicGiants (some with DRM, some not)
HDDT (older, mostly classical m-quality tapes transferred to 24/192)
Gimell Records
HDtracks
See also this website:
List Audiophile Quality Download Sites | Computer Audiophile
Back to the problem of passing a bit-perfect HD track (e.g., in flac) to the 0404 USB family of DACs, let's see if we can clear this up and hope that others in the community find this thread before they get too confused...
"You can send the original bitstream of your recordings, once "unpacked" to the RAW PCM data by WinAmp's built-in FLAC decoder (2.08 in my case), unaltered to the D/A converters via those WDM drivers. No ASIO required."
Although mostly logical (in light of hazy equipment and player documentation and confusion within the audiophile community), this is incorrect. Please see the flow diagram for DirectSound and read the associated explanations from Microsoft at:
Wave and DirectSound Components
As you can see, there are quite a few steps involved in the process. They are divided into user-mode steps, kernel-mode steps, and hardware driver (E-mu) steps. Winamp is the block labeled "DirectSound Application" and the block labeled ""DSound.DLL" is the NullSoft DirectSound output plug-in (out_ds.dll), in our case. Note that the flac decoder is an input driver to WinAmp and has nothing at all to do with the stream from WinAmp to the E-mu hardware.
The pcm stream from the DirectSound plugin is passed to the kernel-mode KMixer. Quoting from the cited Microsoft technote, "Alternatively, the wave stream can be rendered by a USB audio device instead of a WaveCyclic or WavePci device. In this case, the stream cannot bypass KMixer; the USBAudio class system driver (not shown in figure) always passes the stream to KMixer."
Traversing KMixer is not a good thing. Please see "KMixer Driver Sample Rate Conversion and Mixing Policy" at:
KMixer Driver Sample Rate Conversion and Mixing Policy
Please click on all the links at the bottom of the article to learn more than you ever wanted to know about KMixer. Of course, these technotes attempt to put a good spin on KMixer and avoid terms like "re-sampling" and "maximum sample rate," it is impossible to avoid these terms completely in a technical discussion at this level. KMixer does what it is supposed to do, and that is to provide maximum flexibility to a consumer in terms of input, output, and content flexibility. Unfortunately the associated methods may be incompatible with audiophile and scientific applications.
For a good paper on implications for scientific uses, please see:
http://www.speech.kth.se/voice/white...erUsingPCs.pdf (See especially pgs. 16-19.)
KMixer then passes the pcm stream to the E-mu WDM driver. Thus, we cannot use the NullSoft DirectSound plugin to accomplish our objective. So, perhaps we can use the Otachan ASIO plug-in for Winamp. But that leads me to my first original question: "Will the Otachan ASIO plug-in for Winamp talk to the E-MU 0404 USB native ASIO driver?"
Here we encounter another bit of confusion in the community. Some report that the Otachan plug-in will not work without also installing ASIO4ALL.dll. Others report that even after installing both, many artifacts including popping and clicking result. As a result, many get discouraged, try other players, etc. and then abandon ASIO in favor of the DirectSound setup, which just "works."
As it turns out, not only is ASIO4ALL not required, but it is also the source of the artifact-laden sound. The reason is that "ASIO4ALL" is just that, for ALL. That is, it is for all soundcard devices which do not have ASIO drivers. In other words, ASIO4ALL is a translator meta-driver which translates the ASIO stream to pcm that the sound card can understand. So, if install both the Otachan ASIO plug-in and ASIO4ALL, we get an aborted attempt to translate the E-mu destined ASIO stream to "something which the E-mu can understand," resulting in the artifacts.
However, I did not know this when I originally posed the question. I later found out and installed the Otachan plug-in which, indeed DOES talk very nicely to the E-mu driver.
Another confusing piece is the E-mu control panel and its documentation. While the E-mu documentation is not bad, it is incomplete in some places. For example, regarding the Audio Control Panel sample rate setting (pg. 16 in your pdf manual), E-mu tells us "Allows you to set the system sample rate: 44.1kHz, 48kHz, 88.2kHz, 96kHz, 176.4kHz or 192kHz." What does this mean? As it turns out, it means the sample rate for recording. I read a couple of year-old post from an E-mu support person on a forum that I cannot find at the moment. (They were active on some forums before; however E-mu apparently dropped most tech support one year ago. The do not do telephone support because they have one person for the entire world, in Singapore!) Anyway I remember him saying that the 0404 USB does NO RESAMPLING. Thus, setting a rate on the E-mu Control Panel when listening to music from a player through USB does absolutely nothing to the incoming stream. The bit rate of the incoming stream will be whatever the file sampling rate is or is modified to by KMixer. Using ASIO, however, the "Sample Rate" display morphs into a monitor of the actual incoming sample rate, at least on the 0404 USB 3.0. Thus, if right-click on a flac file to see the sampling rate, and play the file from WinAmp to the E-mu via ASIO, it never fails that the 0404 USB reports the actual bit rate of the file.
Now, for the detailed setup, since you were so kind to do it for me (and because there seems to be yet more confusion about how to do this:
(1) The version of firmware and driver on the CD for my 0404 USB 2.0, although just purchased was very old So be sure to download and update from E-mu site.
(2) Download the Otachan ASIO plug-in (vers. 0.70) here:
WINAMP5用 ASIO出力プラグイン (exe version) - ãŠãŸã¡ã‚ƒã‚“ã®MIDI/Audioソフト
(3) Download and install 7z465.exe, a rar-extractor necessary to extract the compressed Otachan ASIO plug-in. (Just Google "7z465.exe."
(4) Extract the plug-in download from Otachan. Look in the "bin" folder; discard the "source" folder. Within the bin folder are a "normal" and an "SSE" folder. Use only the two files from the "SSE" folder, "out_asio(exe).exe" and "out_asio(exe).dll. Copy both of these to the root of the Plugins folder under WinAmp under the "Program Files" folder.
(5) Startup WinAmp and you should see the plug-in that we just installed as a fourth entry in Preferences--> output. Highlight it and press "Configure" to get the configuration dialog box. Make sure that you E-mu device shows in the device pull-down. Most all settings here are devault. Process priority = high; Thread priority = time critical; buffer size = 7; shift output channels = 0; gapless mode (your choice); convert 1 channel to 2 = checked; resampling = definitely not checked (so, disregard additional options under "resampling").
(6) I happen to want all sounds from any source other than WinAmp to go to my standard sound card and to the speakers embedded in my video monitor. To accomplish this, I have the following in WinXP Pro:
(a) Control Panel---> Sounds and Audio Devices---> "Audio" tab: (Whatever your normal soundcard is as default "Sound Playback.")
(b) "Sound Recording" and "MIDI Music Playback" both set to E-mu as default device.
As I said, now when you play a track you should see its sampling rate as encoded reflected in the E-mu control panel.
ASIO is, as far as I have read, the only way to send digital audio through Windows to an output device via USB as a bit-perfect stream.
Please free (anyone) to correct any mis-impressions reflected in this post.
Best regards,
Bruce
Quote:
Originally Posted by .Sup /img/forum/go_quote.gif
Hi guys what are your recommendations for DAC with USB input in 300~400$ range? I want it to have Asio support, not for recording but I'm bypassing kmixer and want to use Asio exclusively. LD MK3 will be connected to it and Sennheiser HD600.
Thanks for your answers
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