envy24control is an application included in the alsa-tools package. It enables controlling the digital mixer, channel gains, and other hardware settings for sound cards based on the VIA Ice1712 chipset (A.K.A. Envy24).
envy24control's user interface is loosely-based on the Delta Control Panel software included with the purchase of M-Audio Delta series audio cards -- most of the tabs, controls, and capabilities are similar in the two applications. However, because they are two separate applications, the user manual for Delta Control Panel software is only marginal useful for envy24control users. This article aims to provide usage guidance for those using ice1712-based cards and envy24control with Arch Linux.
- 1 Installation
- 2 Supported Cards
- 3 Application Overview
- 4 Usage Examples
- 5 See Also
envy24control is included with the alsa-tools package in the community repository:
# pacman -S alsa-tools
envy24control is designed to control ice1712-based cards, including, but not limited to:
- M-Audio Delta 1010
- M-Audio Delta 1010LT
- M-Audio Delta DiO 2496
- M-Audio Delta 66
- M-Audio Delta 44
- M-Audio Delta 410
- M-Audio Audiophile 2496
- Terratec EWS 88MT
- EWS 88D
- EWX 24/96
- DMX 6Fire
- Phase 88
- Hoontech Soundtrack DSP 24
- Soundtrack DSP 24 Value
- Soundtrack DSP 24 Media 7.1
- Event Electronics EZ8
- Digigram VX442
- Terrasoniq TS 88
- Roland/Edirol DA-2496
Understanding Your Sound Card
If you have any of the cards in the list above, know that it has a hardware digital audio mixer built into it (the Ice1712 chip). This mixer accepts digital audio streams from hardware inputs and outgoing streams from software audio devices (such as those provided by JACK), mixes them internally, and then sends the mixed output to the card's hardware outputs. envy24control controls this mixer.
Read Your Sound Card's Manual
It is vital that you understand your sound card's features and capabilities. If you don't, envy24control will not make working with the card any clearer or easier. It's more likely to do just the opposite. Save yourself some frustration: read the manual.
The Monitor Inputs page is effectively a mixer for your card's hardware inputs. It enables you to meter the incoming audio signals and adjust their volumes in the card's onboard "monitor" mixer. For each physical card input, there is a pair of volume faders, mute buttons, and pre-fader level meters. On the far left, there is a meter indicating the overall signal level being routed to the onboard mixer's "pre out." The output of this digital mixer may be assigned to any of your card's hardware outputs on the Patchbay /Router page, by selecting "Digital Mix L/R." (Typically, you'd do this for the hardware outputs that your monitor speakers are connected to, e.g. "H/W OUT 1/2.")
Each mixer input channel has its own level meter that indicates the "pre-fader" levels of the incoming audio signal and are therefore not affected by the fader settings. Each input's meters are color-coded into three sections: green, yellow, and red. The green section is a safe zone; most incoming audio signals should fill at least this section of the meter when recording. The yellow section represents a hotter zone; it is both safe and recommended to adjusting the incoming signal to meter mostly in this zone when recording. The red zone represents danger; when the signal hits 0dB, overload and audio clipping may occur. Adjust the output level of your audio source so that the incoming audio levels do not peak in the red very often or for too long. Let your ears be the judge.
The faders control the signal level in the card's digital mix. They do not control the level of the incoming audio signals -- they are "post-meter." There is no gain control; the faders can only attenuate (reduce) the signal levels. A pair of faders can be "ganged", so that both channels can be controlled as a stereo pair. The mute buttons do exactly what you'd expect: they mute the outgoing channel.
A mono signal can be panned by setting the stereo faders or mute controls accordingly. For example, to pan hard left, mute the right channel. To pan soft right, set the right fader higher than the left. To preserve a stereo signal coming into 2 hardware inputs -- "H/W In 1/2", for example -- mute the right fader on "H/W In 1", and mute the left fader on "H/W In 2."
The highest level setting on the faders is 0dB, or Unity Gain. And since there is no gain, clipping is impossible on the outgoing signal. If the incoming audio signal levels are ideal -- say, -12dB to -3dB (in the yellow) -- it is perfectly safe to set the faders to 0dB (the highest level setting.)
The overall audio signal level of the onboard digital mixer's "pre-out" is indicated by the large meters on the far left, labeled "Digital Mixer." This meter is visible on all pages in the application's UI and displays the same information regardless of which page is active.
When working in this page, remember:
- The input meters display the audio signal levels hitting the hardware inputs of your card -- they are "pre-fader."
- To control the incoming audio signal level, adjust the output level of your source. E.g., your outboard mixer, your mic pre-amp, etc. The incoming audio signal levels and input meters are not affected by adjustments to the faders or mute buttons.
- The volume controls (faders and mute buttons) determine the audio signal level in the card's onboard digital mixer.
For the inquisitive: PCM is an acronym for Pulse Code Modulation.
The Monitor PCMs page is effectively a monitor mixer for your card's software inputs. Software inputs are the digital audio streams sent by your software applications. Typically, on a Linux-based Digital Audio Workstation (DAW), this means JACK. The power of this functionality is most apparent when "Digital Mix" is connected to a pair of audio outputs in the Patchbay / Router tab, and you're mixing multiple sources from both hardware and software inputs See #Usage Examples.
The faders, meters, and mute buttons operate identically to those on the Monitor Inputs page.
- The available software inputs are displayed as "playback_X", where X is a sequential number, in JACK's Connections dialog (in the "Writable Clients / Input Ports" box.) The number of available inputs will vary depending on your specific card.
- "PCM Out 1/2" are typically used by applications like Ardour for their main outs. This is so common, the default signal routed to your card's physical outputs come from "PCM Out 1/2." Therefore, when using your card for monitoring rather than Ardour's, use "PCM Out 3" or higher to monitor the signal you're actively recording to maintain mixing flexibility. See [Usage Examples].
- When connecting the "capture_1/2" output port to input ports in JACK's Connections dialog, be sure to mute the "H/W In 1/2" on the Monitor Inputs page. For example, if you use JACK to connect "capture_1/2" to "playback_3/4", not muting "H/W In 1/2" on the Monitor Inputs page will result in a combination of the direct input hardware signal with a software version of the same signal in the mixer (remember your card is a mixer!), and this usually produces signal phase problems or worse. Depending on the situation, you could even produce a signal loop.
Patchbay / Router
This tab allows you to specify which audio outputs are routed to your card's physical outputs.
envy24control is loosely based on the UI and functionality provided by the Windows/Mac Delta Control Panel software that ships with M-Audio Delta series hardware. The documentation in the cards' user manual loosely applies; be prepared to spend some time experimenting and getting familiar with your card's capabilities and the software. Some manuals for popular Delta series cards: