audiocontrol(1mms) — Commands
NAME
audiocontrol − Controls the volume and port selection for input and output audio devices.
SYNOPSIS
audiocontrol &
DESCRIPTION
The Audio Control program lets you control the volume and port selection for input and output audio devices. It also provides information on the supported formats for these devices.
Digital recommends that both volume control and audio port selection be left to an application such as Audio Control, which controls the input and output volume and port selection for the entire workstation, rather than incorporating control into each application.
CONTROL PANEL
When invoked, Audio Control displays a control panel. The control panel is divided into input and output control sections. These sections contain balance sliders, volume sliders, and port selection buttons. The top sliders control balance for stereo devices and have no effect for mono devices. The bottom sliders control volume.
The output section has a Mute button. Clicking on the Mute button will immediately set the output volume to zero. Clicking on the Mute button again restores the volume to its previous level. Mute is also released if either the output volume or balance sliders are moved. Other applications are not notified of the new volume settings. The volume settings displayed by other applications such as DECsound do not match the settings in use. Conversely, if these other applications are used to change the volume, the settings displayed by Audio Control will not be accurate.
The lower portion of the control panel may display several output device port option boxes. These options are dependent upon the device you are using and are displayed only if these options are supported by the device. You must click on an option box to enable that option.
Options may include activating stereo (if supported) and line out for both input and output or activating the microphone and headset (if used) for input and output.
CONTROL MENUS
The Audio Control File menu items are described as follows:
Exit
Close Audio Control by clicking on Exit.
The Audio Control Options menu items are described as follows:
Settings
This menu item displays a dialog box containing Device and Format option menus. Click on the Device option menu to display a list of audio devices installed on your system.
Click on the device you want to use for Audio Control. Device changes will refresh the control panel, the Show Formats box, and the VU meter display.
Click on the Format option menu to display a list of audio formats supported by the selected input device. Click on the format you want the VU meter to use when opening the input device.
Show Formats
This menu item displays a box containing information on the supported audio formats for the input and output ports of the selected audio device. You can use the input/output box in the upper right corner to switch between input and output formats.
Show VU Meter
Click on this item to display a VU meter, which can be used to monitor the input decibel (dB) level of your selected audio device. The meter will display either stereo or mono, depending upon the selected device. The meter should show green most of the time and rarely show yellow. If the meter constantly displays yellow or red, you should lower your input volume controls.
Audio Control has a resource file that specifies default settings for the VU meter. The default file is /usr/lib/X11/app-defaults/AudioControl. To modify the settings, copy this file to your home directory and edit the values.
The vu_update_interval value controls how often the VU meter is updated. This update frequency is displayed in milliseconds. A lower value makes the VU meter more responsive but increases the load on the mmeserver. The default value is 60 ms.
The vu_peak_persistence value controls how long the VU meter latches (marks) the peak decibel values. Setting the vu_peak_persistence value to zero disables peak latching. The default value is 1000 ms.
NOTE: Digital recommends that you limit the time you display the VU meter. The VU meter requires a large amount of system resources and should be displayed only when needed.
FILES
/usr/bin/mme/audiocontrol
/usr/lib/X11/app-defaults/AudioControl
/usr/lib/mme/help/audiocontrol.hlp
/usr/lib/X11/uid/audiocontrol.uid