User manual M-AUDIO DUO

[. . . ] . 27 Introduction Congratulations on your purchase of the Duo, designed and manufactured by M-Audio. The Duo is a complete USB audio solution for your PC or Macintosh computer. With two inputs and two outputs of 24-bit audio and up to 96kHz sampling frequencies, coupled with two high quality mic preamps, the Duo utilizes the power and convenience of USB audio in a convenient half-rack size unit. The Duo lets you operate its analog inputs and outputs at either +4 or -10 line levels, gives you a S/PDIF output, plus a headphone output for personal monitoring. [. . . ] Some ribbon mics definitely should NOT receive phantom power, as this could damage them. Using the Pad Switch On the front panel of the Duo, a "Pad" Switch is provided to attenuate a signal that is too hot before it gets to the mic preamp. If you find that your signal tends to clip even when the gain control knobs are set extremely low, try engaging the Pad Switch. When pressed and locked to the in position, the corresponding signal will be trimmed by 20dB. Gain reduction is bypassed when this switch is in the out position. Standalone Mode The Duo can also be used in a "Standalone" mode, independent of your computer. Pressing the "Standalone" switch on the front panel and locking it to the in position will connect the input channels, Channel 1 and Channel 2, directly to the Line Out, S/PDIF Out, and Headphone Out of the Duo. The Duo can be used as an analog to digital, or "A/D" converter. A signal present at either the Mic Inputs or the Line Inputs will be converted to a digital audio signal and sent to the S/PDIF Out on the Duo. This will allow the Duo to be used with another digital audio device that accepts a S/PDIF signal, and not as a digital audio interface in conjunction with your computer. The Duo can be used as a microphone preamp, again, independent of your computer. A signal at the Mic Inputs of the Duo will appear at the Line Outs, allowing you to use the Duo's mic preamp in a sound reinforcement situation or similar instance where its use as a computer interface is not necessary. A "direct monitoring" capability can be achieved when Standalone mode is engaged while the Duo is in use as a digital audio interface in conjunction with your computer. This will give you zero latency monitoring of the signals present 13 at either the Mic Inputs or the Line Inputs of the Duo. You will, however, not be able to hear the software outputs from your computer in this case, so this option may only be useful to you when laying down your first recorded tracks, i. e. , when there is no other audio playing back from your computer. In cases #1 and #2, the sampling rate for the Duo's A/D converter will be determined by the DIP switch settings on the bottom of the unit. See the section, "Bottom of the Unit" earlier in this manual. It will give you more information on how to set the DIP switches for the sampling rate of your choice. The bottom of the Duo has a silk-screened guide that reveals the DIP switch settings. In case #3, the sampling rate for the Duo's A/D converter is controlled by your music program or operating system. This is true whenever the Duo is attached to the USB port, and both the Duo and the computer are powered on. Duo Operation on the PC The USB Audio Configuration Manager When the Duo drivers are installed, a control panel is also installed into the System Tray on your Windows taskbar. This control panel is the "USB Audio Configuration Manager. " The configuration manager allows you to choose between the Duo's ASIO or EASI drivers and the Windows "MME" drivers, which are WDM compatible with Windows 98SE or higher. To open the USB Audio Configuration Manager, locate the M-Audio icon on the right side of your taskbar, then double click the M-Audio icon. MME drivers allow a device to be used in Windows, as well as music applications that utilize these Windows drivers, and will appear as "USB Audio Device" both in Windows and in your music program. ASIO is a driver model developed by Steinberg, and is used by music programs that have adopted the ASIO driver standard. [. . . ] These are extremely important pieces of information to know when calling us. Finally, Mac users using OS X must know what their System Administrator Password is. Symptoms: Please be ready to describe the symptoms to the best of your abilities (crackle, stuck notes, jitter, etc. ) and whether or not they are consistent (Do they happen at the same place at the same time --each time?You may also want to note when you started experiencing these problems and whether it was related to any specific incident or not. [. . . ]