User:Woozle/M-Audio Delta 66
This is about trying to use the M-Audio Delta 66 multitrack audio ADAC in Linux. This apparently uses the Envy24 chipset, for which there are drivers.
As of 2017, the Envy24 drivers are part of the standard distro and seem to work pretty well. There are two different control panels (approximately replicating the functionality of the one provided by M-Audio for Windows); "Mudita24" did not seem to work right, but "Envy24 Control Utility" (E24CU for short) more or less does -- as far as I can tell what it is supposed to be doing, anyway.
Envy 24 Control Utility
I'll do a quick rundown of what I do understand in the E24CU, by tab, as far as the mixing controls go.
Monitor Inputs
This shows what's coming into the various inputs, and also lets you adjust their levels within the stereo "digital mix".
The D66 has 4 analog inputs on the breakout box and a stereo pair for the S/PDIF (RCA jack) on the card; this panel displays those as:
- H/W In 1
- H/W In 2
- H/W In 3
- H/W In 4
- SPDIF In L
- SPDIF In R
Pretty straightforward.
Monitor PCMs
This one, I pretty much don't get. There are 8 pairs, labeled PCM Out 1 through PCM Out 8. There are volume sliders for L and R in each pair, but nothing seems to affect anything else.
Patchbay / Router
This one mostly makes sense. As with the inputs, the D66 has 4 analog outputs and a stereo pair for the S/PDIF (RCA jack) on the card. This panel displays those as:
- H/W Out 1 (L)
- H/W Out 2 (R)
- H/W Out 3 (L)
- H/W Out 4 (R)
- S/PDIF Out (L)
- S/PDIF Out (R)
Each one can accept input either directly from any of the Monitor Inputs or from the "Digital Mix" (i.e. the combined output of the attenuators in the Monitor Input tab)
The exception to this rule is that H/W 3 and 4 cannot accept Digital Mix input. Other than that, inputs are completely cross-patchable to outputs.
Audacity
input
This may be dependent on which audio system you have installed, but using ALSA it would seem that Audacity lies to you (or else is being lied to by the audio system) about the source of its inputs.
On my system, it lists 4 inputs each from 5 different audio systems:
- HDA ATI SB: ALC861 Analog (hw:0,0)
- M Audio Delta 66: ICE 1712 multi (hw:1,0)
- sysdefault
- pulse
- default
For each system, the 4 inputs listed are always:
- Front Mic:0
- Line:0
- CD:0
- Rear Mic:0
It's not clear how these are derived, since the D66 does not have mic or CD inputs; all are line level. In any case, it doesn't seem to matter which D66 input you pick; you always get the same signal, which seems to be HW IN 1+2.
So basically, digital routing kind of fails here; whatever it is you want to be recording has to be on HW IN 1 and HW IN 2.
output
Make sure that you're sending the appropriate playback channels to the appropriate speakers -- see the "Monitor PCM" tab to control this. Typically, you'll want to un-gang the channels you want to include (otherwise you get center/mono for those channels). When Audacity's output is set to go to the M-Audio (rather than somewhere else), it apparently sends the two mix output channels to PCM Out 1 and PCM Out 2 -- so ungang these and set PCM Out 1 to left-high / right-low (so the left mix channel will go to the left stereo channel) and PCM Out 2 the opposite (so the right mix channel will go to the right stereo channel).
I think this makes sense, but I should probably draw a diagram at some point.