The USB Dual Pre is a full-featured high quality dual portable preamplifier and computer interface packed into a compact rugged case. It is designed to work over a wide variety of applications from remote field recording to desktop/studio tracking. Each of the two low noise input channels has up to 48 dB of clean gain with signal present and clip LED indicators. Inputs can be either XLR balanced or 1/4-inch TRS. Each of the 1/4-inch TRS outputs is buffered low impedance balanced. The USB Dual Pre can be externally powered from the mains via a wide range of external power adapters, or from an internal 9 Volt battery, or from the USB bus itself, or any combination of these power sources. When running off of the battery alone, you should get in excess of 50 hours of opera- tion when phantom power is off. Battery life drops to around 20 hours (depending on microphone) when phantom powering from the battery alone (still enough time to get through a session). The built-in low noise +48 Volt phantom power supply allows you to power up to 2 microphones as well as the preamplifier when running from any power sources including the USB bus. For monitoring, an 1/8-inch TRS mini headphone jack with level and monitor mix controls on the rear allow for latency free local monitoring of the inputs while recording as well as playback monitoring of the USB bus. The monitor mix is also routed to the 1⁄4-inch TRS balanced outputs. This lets you use the 1/4-inch outputs as either a preamplifier out or as the monitor feed to your powered monitors. The USB interface is fully compliant with the USB 1.1 specification and uses USB adaptive mode for playback and USB asynchronous mode for record. It will work with the USB audio device drivers built into Windows 98SE/ME/2000/XP/Vista 32bit and Apple OS9.1/OSX computers with native USB support. No special drivers are needed. The compact black anodized all aluminum case with rubber sides makes for a rugged design. The USB Dual Pre will provide years of trouble free service and its high quality audio channels and versatile powering options make the USB Dual Pre the obvious choice in a wide variety of applica- tions from Podcasting/Broadcasting to Tracking and Monitoring. With the USB Dual Pre, your laptop, and a pair of quality microphones you can do some serious remote recording. Key Features Include: • USB Connectivity to Desktop and Laptop Computers • Low Noise Fully Balanced XLR and 1/4-inch TRS “Combo” Inputs • Up to 48 dB of Clean Gain • Built-in Low Noise +48 Volt Phantom Power Supply • Latency Free Monitoring Mix and Level Controls • Independent Channel Gain Controls • 1/4-inch TRS Balanced Monitor and 1/8-inch Headphone Monitor Outputs • Includes Recording & Production Software • Compact, Stackable all Aluminum Chassis • Flexible 3-way Power from USB, External Supply, or 9 Volt Battery 3 CONNECTIONS: Left and Right “Combo” jacks on the front allow for either XLR or 1/4-inch TRS input connections. The XLR Input connections are used primarily for balanced microphone input. Pin 2 is positive, pin 3 is negative, and pin 1 is ground. +48 Volt phantom power (when enabled) is supplied to pins 2 and 3 and pin 1 acts the ground return. Do not lift pin 1 when using phantom power. If you are using the XLR Inputs with a balanced low line level signal or a microphone that does not require phantom power, make sure that phantom power is turned off. Maximum gain from the balanced XLR Inputs to the balanced 1/4-inch TRS Monitor Outputs is 48 dB. These inputs can handle microphone signals up to +6dBu before clipping. The 1/4-inch Input connections are used for instrument or low line level balanced or unbalanced signals. The high fixed input impedance works well with guitar and other passive instrument pickups. You can use an unbalanced or balanced plug with this connection. Maximum gain from the 1/4-inch input to the balanced 1/4-inch TRS Monitor Output is 48 dB with a balanced source and 42 dB with an unbalanced source. When the Gain control is at minimum, this input can handle signals up to +6dBu. The 1/4-inch Monitor Output jacks are active balanced with the Tip positive, Ring negative, and Sleeve ground. With an output impedance of 600 Ohms and a maximum output level of +10dBu it can provide clean balanced signals for long cable runs. Normally you would use this output to go directly into a power amplifier, powered monitors, recording system, or a mixer’s balanced line or insert inputs. Though we do not recommend it, if you have to go directly into the balanced microphone input on a mixer make sure that phantom power is off at the mixer. The mixers input pad and level controls should be set for minimum gain, and the Monitor Level control on the USB Dual Pre should be set at a low enough level to prevent overdriving the mixers input section. The 1/8-inch Headphone Monitor Output jack is stereo unbalanced TRS and has an output imped- ance of 50 Ohms. It can accommodate a wide variety of headphone models. Maximum output level is +4dBu. The power connector on the rear allows for external AC powering. 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 comput- er 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 simulta- neous 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.
Posted on: Wed, 28 Aug 2013 07:53:57 +0000