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Thuneau Allocator and onboard C-Media 9880L - detailed method.

Posted by Presto (A) on November 6, 2006 at 13:04:59

You can get a three-way active Audio PC going and all you need is a mobo with a HD Audio Codec like the C-Media 9880L or the Realtek ALC 880, and a receiver with a 6-channel "external decoder" input.

You will need the following sofware/drivers:

1. Thuneau's Frequency Allocator / Phase Arbitrator:
http://www.thuneau.com/allocator.htm

Free to try. $89 USD to buy.

2. Virtual Audio Cable 4.03 ($49 to buy):
http://nrcde.ru/music/software/eng/vac.html

3. ASIO4ALL version 2.7:
http://www.asio4all.com/

4. Steve Monk's Kernel Streaming Output Plugin (If using WinAmp):
http://www.stevemonks.com/ksplugin/

5. Intel's UAA HD Audio Driver (KB888111.exe)

http://downloadfinder.intel.com/scripts-df-external/Detail_Desc.aspx?strState=LIVE&ProductID=2474&DwnldID=11036&agr=Y&lang=eng&PrdMap=2474

WARNING: Be educated about the pros and cons of this driver:

http://support.microsoft.com/kb/888111
http://www.thehotfix.net/kb/KB888111.htm

***Then let the installation games begin!***

1] Install the KB888111.exe patch. Your C-media 9880L (or Realtek ALC 880) device in the hardware manager should change from its original name to "UAA HD Audio Driver". Reboot before proceeding.

2] Install the Virtual Audio Cable and create a new cable (Virtual Cable 1) and set the bitrate to whatever you play to play back. This is done by setting the number of cables to "1" and pressing "Set". (For RBCD you want min and max channels = 2, min and max samplerate = 44100, min and max bit depth = 16.

3] Install ASIO4ALL (if you don't have it already] and enable ONLY the input of Virtual Cable 1 and the OUTPUT of the HD Audio Render device. Disable all other ASIO4ALL devices found. (Thanks to the ASIO4ALL team for this wonderful piece of software!)

4] Install a $10 (or spare) soundcard into an available PCI slot and select it for PLAYBACK and RECORDING under Audio Devices in the WinXP Control panel (This will keep your onboard Codec OUT of the kmixer and keep Windows sounds and alerts OUT of your onboard Codec).

5] Install KS (Kernel Streaming) output in Foobar (or Winamp) if you have not done so already. In foobar, set your bitrate in the playback options to "16 bit fixed point" if playing RBCD. Be sure to select the Kernel Streaming output of your player, and set the KS output to use Virtual Cable 1! (Special thanks to Steve Monk for the KS Output plugins for Winamp! Nice work!)

6] Install the Frequency Allocator. Under Audio Setup select ASIO4ALL. Under routing select "Virtual Cable 1 1 and 1 2" for Left and Right Inputs. Select "HD Audio Render 1" through HD "Audio Render 8" sequentially for the 8 outputs of the allocator.

7] Ensure crossover functions are entered correctly and necessesary filters are ACTIVE!

8] Connect the six outputs to your HT receivers "External Decoder" inputs. CHECK YOUR CONNECTIONS. Connect tweeter only after hearing "lows" come the woofers, and "mids" coming from the mids.

WARNING. Be aware that the UAA HD Audio driver maps channels to the C-Media 9880L audio jacks in a rather "funny" way. There are six jacks in an array looking at the back of the computer.

Grey, Blue, Pink
Green, Black, Orange

If you have mapped the outputs sequentially (1 through 8) in the Allocator, Green is "Low", Orange is "Mid1", Black is "Mid2" and Grey is "High". Notice we jump from Green to Orange to Black not Green, Black, Orange, as one might expect. THIS IS DEFINATELY COUNTER INTUITIVE. Test all outputs with a cheap driver first. I'm not taking responsibility for fried tweeters! Do your own checks if using the Realtek ALC 880!

9] Marvel at just how good a cheap onboard audio codec can sound with the amazing Frequency Allocator and Phase Arbitrator! Just imagine how good this could sound with a *real* ASIO soundcard solution!

The Allocator is said to put out 24 bit audio. I have had success (with no pitch change problems or anything) with the following types of audio files (all .wav):

16 bit, 44.1 kHz (RBDC)
16 bit, 48 kHz (from MPEG2 Video)
24 bit, 48 kHz (Hi-res recordings of analog sources)
24 bit, 96 kHz (Hi-res recordings of analog sources)
24 bit, 192 kHz (Hi-res recordings of analog sources)

Congratulations Jan! Your Frequency Allocator / Phase Arbitrator is amazing! If it sounds this good using a cheap onboard Codec and ASIO4ALL - then I can't imagine how good it's going to sound with a proper ASIO soundcard with mixing capabilities and super quality external DACS.

Trouble shooting:

In ASIO4ALL:

-Check to make sure that Virtual Cable 1 is the ONLY input selected
-Check to make sure that HD Audio Render 8 x 192khz is the ONLY output selected.

In your media player:

-Check to make sure player is set to Kernel Streaming and Virtual Cable 1 is selected.
-Check to make sure your output bitrate is set to 16 bits for RBCD
-Play a file in your media player and open up virtual audio cable. You should see 1 output stream.

In the Allocator

-In the Allocator “Audio Settings” Menu make sure “ASIO4ALL” is the ASIO device selected
-In the Allocator “Audio Routing” Menu make sure that inputs are Virtual Audio Cable 1 and outputs are
HD Audio Render 1 through 8.
-When playing back a track, ensure that the “stream” button is depressed on the Allocator control panel

**When the stream button is depressed and no meter levels are showing up, you either have a problem with your media player / ASIO4ALL settings / Routing settings OR you have NO FILTERS ACTIVE and SELECTED.

** When the stream button is depressed and you DO have level meters show up for the Allocator outputs but no sound, you have a problem with your ASIO4ALL, HD audio device driver, or connections to your receiver.

Known issues and fine print for the C-Media 9880L / Allocator combo method above:

a) This method has only been thoroughly tested with the C-Media 9880L codec. It may well work for other codecs that use the KB888111 UAA HD Drivers – but in that case YOU are the “Beta Tester”!

b) Be aware of the implications of installing KB888111 before you proceed. Create restore points and make backups as needed. Install at your own risk. (It's not THAT big of a deal - I switch between UAA and factory drivers all the time - but you've been warned)

c) The counter intuitive mapping of channels as described above.

d) Your C-Media 9880L / Realtek ALC 880 Mixer Icon becomes NON-OPERATIONAL under the KB888111 fix. This is not a glitch. It means Windows XP is now the driver instead of the factory driver with the "fancier" mixer/control panel - but no mixer is needed anyways since we're using ASIO4ALL and NO VOLUME CONTROLS. Only the Allocator's volume control will be active (and any volume controls enabled in your playback software). If you re-install your factory driver, the functionality of the mixer icon is restored. (It does for me at least - again, know the issues with this KB and decide for yourself.)

e) Sometimes you only see 7 out of 8 "HD Audio Render" channels show up on the Allocator's Routing table . This seemed to be intermitted and then went away - now I see all 8. If you are only doing a three way active system you're only using the first six anyways. Watch for this.

f) I am not sure that the "Azalia" HD Codecs like Cmedia 9880L and Realtek ALC 880 can handle 44.1/88.2/176.4 kHz and I highly doubt it. Then again I am not sure what sampling rate the Allocator is spitting out - I am assuming sampleratein=samplerateout but I need to confirm that with Jan.

g) You may lose input functionality of your onboard soundcard. If you plan to do measurements while running the Allocator, you WILL need a second (PCI) Soundcard.

h) This is a crazy solution is for people who are either extremely adventurous or cheap or both. But the SQ to money ratio will blow your mind.

Have fun. And don't rush....

Cheers,
Presto

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