User manual ART PRO VLA II

[. . . ] Pro VLA IITM PROFESSIONAL TWO CHANNEL VACTROL®/TUBE LEVELING AMPLIFIER USER'S GUIDE IMPORTANT SAFETY INSTRUCTIONS ­ READ FIRST This symbol, wherever it appears, alerts you to the presence of uninsulated dangerous voltage inside the enclosure. Voltage that may be sufficient to constitute a risk of shock. This symbol, wherever it appears, alerts you to important operating and maintenance instructions in the accompanying literature. Please read manual. Read instructions: Retain these safety and operating instructions for future reference. Do not open: Aside from two vacuum tubes, there are no user serviceable parts inside. [. . . ] Mounting location is not critical, however for greater performance reliability we recommend that you not place the unit on top of power amps, or other sources of heat and/or strong magnetic fields. The tube circuitry needs about a minute to "warm up" and stabilize from a cold power up. 3 Unpacking Your Pro VLA II was packed with care at the factory. The shipping carton was designed to protect it during initial shipment. Please retain this carton for use in transporting the Pro VLA II when it is not installed in a rack, or in the unlikely event that you need to return your Pro VLA II for servicing. The shipping carton should contain: - The Pro VLA II - The owner's manual - User Registration Card AC Power Hookup The Pro VLA II has an internal power supply designed to operate at 100 to 125VAC, 50 to 60Hz. Units manufactured for use outside of the United States of America have been modified to comply with the required electrical specifications. If the cable becomes cut or damaged, discontinue its use and have it replaced before operating the Pro VLA II. The power source must provide a good ground connection, and the ground pin on the mains plug should never be defeated. Analog Audio Connections Audio connections to and from the Pro VLA II are: Balanced input: [XLR] Pin 2 = Hot (+), Pin 3 = Cold (-), Pin 1 = Ground [1/4"] Tip = Hot (+), Ring = Cold (-), Sleeve = Ground Balanced output: [XLR] Pin 2 = Hot (+), Pin 3 = Cold (-), Pin 1 = Ground [1/4"] Tip = Hot (+), Ring = Cold (-), Sleeve = Ground Unbalanced 1/4" cables may be used with no damage to the Pro VLA II. We recommend using only highquality cables equipped with the appropriate connectors. 4 FRONT PANEL CONTROLS and INDICATORS Power The POWER switch turns the power on and off to the unit. The Pro VLA II should be turned "on" with all monitor levels turned down to protect against any "thumping" caused by power up. Likewise, the Pro VLA II should be turned "off" after turning all monitor levels down. In this case if the input signal increased 12dB over the threshold, the output level would only rise by 3dB. In general, compression ratios of 10:1 and greater are considered "limiting". The Pro VLA II may be used as either a compressor or a limiter with all of the following: - Multitrack recorder, DAT machine, hard disk recorder, or analog recorder. - Between preamplified electronic musical instruments (synthesizers, guitars, bass, samplers, acoustic instruments with pickups) and other line-level equipment. 5 FIGURE 1 ­ Channel 1 Controls Output Level Control The OUTPUT LEVEL control serves two functions. The CH1 knob always controls the output level of CH1, but can also serve as a "MASTER" output level when the Link Mode is active. The CH2 OUTPUT LEVEL control operates as a standard CH2 level control or as a "BALANCE" control when the Link Mode is active. In Link Mode when the BALANCE control is turned fully counter-clockwise the CH1 output is fully on and CH2 output is fully muted. When turned fully clockwise the CH2 output is fully on and CH1 output is fully muted. Attack Control The ATTACK control sets the time it takes the Compressor/Limiter to respond to increases in signal level (by reducing gain). You can use this control to shape the "front end" of the dynamics envelope. One example is to listen to a snare hit and adjust the ATTACK control. As the attack time goes longer (the knob is turned clockwise) you should hear more of the thump in the compressed snare. [. . . ] Adjust the controls of the Pro VLA IITM to achieve the desired amount of compression. 11 WARRANTY INFORMATION Limited Warranty: Applied Research and Technology will provide warranty and service for this unit in accordance with the following warrants: Applied Research and Technology, (ART) warrants to the original purchaser that this product and the components thereof will be free from defects in workmanship and materials for a period of three years from the date of purchase. Applied Research and Technology will, without charge, repair or replace, at its option, defective product or component parts upon prepaid delivery to the factory service department or authorized service center, accompanied by proof of purchase date in the form of a valid sales receipt. Exclusions: This warranty does not apply in the event of misuse or abuse of the product or as a result of unauthorized alterations or repairs. This warranty is void if the serial number is altered, defaced, or removed. ART reserves the right to make changes in design or make additions to or improvements upon this product without any obligation to install the same on products previously manufactured. [. . . ]