User manual ART DST-825

[. . . ] If the provided supply does not fit into your outlet consult your service agent. Route the power cord so that it is not likely to be walked on, stretched or pinched by items placed upon or against it. Grounding: Do not defeat the grounding and polarization means of the power supply. Moisture: To reduce the risk of fire or electrical shock do not expose the unit to moisture or use in damp or wet conditions. [. . . ] The USB Dual Pre can operate from any external power source that provides 7. 5 Volts to 12 Volts, AC or DC @ 150mA or more. Battery and USB bus powering are also possible when AC power is not available. 4 The USB connector is USB 1. 1 compliant and should be used to connect directly to one of the USB connections on your computer. This connection also powers the USB circuitry inside the USB Dual Pre and will power the whole product if no other power source is available or active. To your computer this connection looks like a "USB Audio CODEC" and your computer then controls the sample rate. Since the USB connection will be carrying high quality digital audio to and from your computer as well as bus powering the USB interface, we suggest that you use a high quality shielded USB cable for best performance. Ideally you should connect directly to one of the USB inputs on your computer. Connecting through a shared hub can reduce power and bandwidth that is available for each USB device and should be avoided when possible. Though the USB Dual Pre is compatible with USB 1. 1 and 2. 0 interfaces, USB 2. 0 is preferred for the cabling and computer connection as it allows for more system bandwidth. If you must use a hub, it should be a powered USB 2. 0 compliant hub for best results, This is especially important if you plan on using multiple units for more channels of simultaneous digital audio input. Both analog output jacks and the USB Out can be used at the same time, which is handy when you want to run to a mixer and instrument amp in a live situation, or when connecting to a computer or recording system and locally monitoring your source with headphones. For a typical recording application where you want to add tracks of audio using the USB bus to your computer, while monitoring the mix externally for low latency, we suggest the following: Connect your instrument and/or microphone to the USB Dual Pre inputs, then connect to your computer with a USB cable. Use the 1/4-inch monitor output jacks to feed your powered monitors or analog monitor system and/or use the 1/8-inch jack for local headphone monitoring. Then use the Monitor Mix control to locally adjust between the new tracks and the computer playback signal. The new track that you are recording will be in real time and have no latency in your monitoring system. 5 CONTROLS and OPERATION: The Left Gain and Right Gain Controls directly adjust the input amplifiers giving you control over the dynamic range of your source. The red "Clip" LED comes on just before clipping (2dB before digital clipping and 6 dB before analog clipping) and should light on musical peaks only. The green "Signal" LED comes on around 10dB before the "Clip" LED and indicates how far below clipping your signal is. The "Signal" LED has a longer release time and should be on much of the time during performance and if not it indicates that your signal or input gain may be too low for best results. A brief note from customer service: Once in a while a customer will call and say: I think my ART preamp is "noisy". If you experience unwanted "noise" in your system when you use a stand-alone preamp, please consider what your signal is and where you're sending it. Choose the mixer device: "USB Audio CODEC" or Programs =>Accessories =>Entertainment =>Volume Control=> Options=> Properties Choose the mixer device: "USB Audio CODEC". WINDOWS VIsta: Settings => Control Panel => Sound => Playback Tab and Record Tab. Choose: "USB Audio CODEC" Mac OS9. 1+: Control Panels => Sound. Choose: "USB Audio CODEC" Mac OS10+: System Preferences => Sound. Choose: "USB Audio CODEC" Your computer audio output "Speaker" is now set to be the "USB Audio CODEC" and playback audio is routed to the USB Dual Pre. This must be done while the USB Dual Pre is connected to the computer and powered on. After the above settings are made, your computer will automatically reconfigure itself back to these settings every time the USB Dual Pre is reconnected to the computer. [. . . ] Refer to the LEDs on the front for a visual measure of input gain, and then route the output to a mixer, workstation, or computer via the 1/4-inch or USB output. Since the USB Dual Pre can be battery powered or run totally off the USB bus, it is ideal as a portable microphone preamp for remote performance or laptop recording. Phantom Power Supply: Many mixers, workstations, and computer interface boxes will not supply +48 Volt phantom power on all microphone inputs. The USB Dual Pre is a perfect solution to this problem, letting you connect any microphones to your existing mixer or computer. Once again portable laptop recording with high quality condenser microphones that require real phantom power is possible. Instrument DI: The USB Dual Pre will work well as a very functional DI for Bass, Acoustic Guitar and virtually any other instrument with a 1/4-inch or XLR output. [. . . ]