User manual DBX 386

[. . . ] ® 386 Dual Vacuum Tube Preamp w/Digital Out User Manual IMPORTANT SAFETY INSTRUCTIONS CAUTION RISK OF ELECTRIC SHOCK DO NOT OPEN WARNING FOR YOUR PROTECTION PLEASE READ THE FOLLOWING: KEEP THESE INSTRUCTIONS HEED ALL WARNINGS FOLLOW ALL INSTRUCTIONS CLEAN ONLY WITH A DAMP CLOTH. DO NOT INSTALL NEAR ANY HEAT SOURCES SUCH AS RADIATORS, HEAT REGISTERS, STOVES; OR OTHER APPARATUS (INCLUDING AMPLIFIERS) THAT PRODUCE HEAT. UNPLUG THIS APPARATUS DURING LIGHTNING STORMS OR WHEN UNUSED FOR LONG PERIODS OF TIME. A T T E N T I O N : RISQUE DE CHOC ELECTRIQUE - NE PAS OUVRIR W A R N I N G : TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK DO NOT EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE The symbols shown above are internationally accepted symbols that warn of potential hazards with electrical products. The lightning flash with arrowpoint in an equilateral triangle means that there are dangerous voltages present within the unit. [. . . ] Set the front panel of the 386 to the desired settings, including phantom power, 20 dB pad, phase, etc. Connect the line output of the 386 to the console's LINE INPUT, and ensure that the console's input selection switch is set to LINE, and the console's gain control is set appropriately low. Turn the OUTPUT LEVEL control to the 12 o'clock position, and apply power to the 386. Make sure your console's gain fader is at the nominal level and begin to slowly increase the gain of the 386 using the DRIVE control. You should increase the gain until the mixing/recording device is operating at nominal signal input level. ® 6 3386 User Manual 386 Analog Applications Section 2 2. 3 Direct Connection to a Recorder 1). Make microphone connections, being careful to keep the DRIVE control in the minimum (+30 dB) position. Connect the 386's Line outputs directly to the audio inputs of your recorder. Enable the record function of the specific track of the recorder and open the specific tape track return in the console which corresponds to the track to which the 386 is connected. As you increase the setting of the DRIVE control, you should begin to hear the input of the 386 running through the recorder and returning to your console as a tape return. ® 386 User Manual 7 386 Section 3 DIGITAL APPLICATIONS APPLICATIONS DIGITAL ® Section 3 Digital Applications 386 3. 1 Digital Output Front Functions of the 386 Dither Switch This switch is used to select the dither type algorithms including: TPDF, SNR2 , or None. Dither is random noise that is added to the audio signal which effectively eliminates the harmonic distortion created by truncation. The LED will be lit RED for the SNR2 or GREEN for the TPDF dither algorithm. When the LED is off, dithering is not in use. Shape Switch This switch selects the Shape 1, or Shape 2 psycho-acoustic noise-shaping curve. Shape 1 utilizes a mild psycho-acoustic curve, while the curve used in Shape 2 tends to be more aggressive. Please see the "Noise Shaping" graph in section D. 1 of the appendix. When the LED is off, the noise-shaping algorithm is not in use. Sample Rate Switch This switch selects the digital output sample rate of either: 44. 1, 48, 88. 2, or 96 kHz. The LED will not be lit for 44. 1 kHz, GREEN for 48 kHz, RED for 88. 2 kHz and YELLOW for 96 kHz. Word Length Switch Selects output wordlength of 16, 20, or 24 bits output resolution. The LED will not be lit for 16 bit, GREEN for 20 bit, and RED for 24 bit. Output Format Selects either the AES/EBU or S/PDIF digital output format. The LED will be red for AES/EBU and green for S/PDIF. 3. 2 Digital Output Rear Panel Connections ® 10 386 User Manual 386 AES/EBU Digital Connector S/PDIF Digital Connector Digital Applications Section 3 The 386 provides AES/EBU digital output formating through the XLR connector. Be sure to use short lengths of 110 digital cables rather than standard XLR to XLR cables. Using the correct cables will prevent digital dropouts and other interconnection problems. The 386 provides S/PDIF digital output formating through the RCA coaxial connector. Be sure to use short lengths of 75 digital cables or 75 video cables rather than standard audio RCA to RCA cables. Using the correct cables will prevent digital dropouts and other interconnection problems. NOTE: Although digital information is coming out of both XLR and RCA jacks simultaneously, the correct format will only appear at the output for the format type selected. [. . . ] 3a through 3d illustrate what happens when you overload an A/D converter without Type IVTM. 3a shows an input signal having both low-frequency and high-frequency components. 3b) at the A/D converter, a disproportionate amount of highfrequency signal information is lost compared with the low-frequency information. The low and high-frequency components of the signal are separated in Fig. [. . . ]