Shure fp51 owners manual

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INPUT LEVEL IMIC I1 IN dBV COMPRESSION SYSTEM INPUT-OUTPUT CHARACTERISTICS FIGURE 1 Gated Memory Threshold: -90.5 dBV typical at maximum input gain (mic); -40.5 dBV typical at max- imum input gain (line) Recovery: In "hold" position, less than 20 dB gain recovery after 1 minute VU Meter Dual-range, 3-function (output level in dB, gain reduction in dB, battery check), illuminated (ac operation only) Gated MemorylPeak Indicator With meter switch in VU position, lights 6 dB below clipping; with meter switch in Comp position, lights when gated memory is "holding" Noise Equivalent lnput Noise: - 129 dBV (low-impedance microphone, 150 ohms, 300 to 20,000 Hz) into 600-ohm load at full gain Equivalent lnput Hum and Noise: -127 dBV (low- impedance microphone, 150 ohms, 20 to 20,000 Hz) into 600-ohm load at full gain Output Noise: -77 dBV maximum (output control full counterclockwise [off]), -40 dBV maximum (output control full clockwise [on]) (input control down, 300 to 20,000 Hz) Output Hum and Noise: -75 dBV maximum (output con- trol down), -38 dBV maximum (output control up, input con- trol down, 20 to 20,000 Hz) Distortion 0.4% THD, 30 to 20,000 Hz at + 15 dBm output; 0.5% or less IM distortion at + 15 dBm output into 600 ohms Common Mode Rejection 65 dB minimum with input of -20 dBV at 100 Hz Control Interaction Less than 1 dB with any control combination Overload and Shorting Protection Shorting outputs, even for prolonged periods, will cause no damage; microphone input will not be damaged by signals up to 3V Low-Cut Filters 6 dB per octave rolloff at 150 Hz Phase All outputs in phase with respect to all inputs. Pin 2 is "high" with respect to pin 3; pin 1 is ground. Tip of mix bus jack in phase with pin 3. Tip and ring of headphone jacks in phase with pin 2 Tone Oscillator 1 kHz; + 15 dBm minimum at line output with output level full up Phantom Power 30 Vdc nominal, 3.3k series resistance, automatically dis- abled with input switch in Line position Operating Voltage Ac Operation: 120 or 240 Vac -r-10% (internally selectable), 50160 Hz, 5.5W Dc Operation: 27 Vdc nominal at 27 mA typical no-signal, 30 mA typical at 0 VU (+4 dBm) output; 21.5 Vdc minimum; battery life approximately 10 hours with alkaline batteries at + 4 dBm output in continuous use; three 9-volt bat- teries, type NEDA 1604A (Duracell MN1604 or Eveready 522 recommended) Temperature Range Operating: -18O to 57OC (0° to 135OF) Storage: -2g0 to 71°C (-20° to 160°F) Dimensions 79.5 mm H x 310 mm W x 230 mm D (3-118 in. x 12-7132 in. x 9-1132 in.) Weight Net: 2.75 kg (6 Ib 1 02) Packaged: 3.25 kg (7 Ib 3 oz) Certifications Listed by Underwriters Laboratories Inc.; listed by Cana- dian Standards Association as Certified CONTROLS AND CONNECTORS Power Off-On Switch: applies power to the FP51 circuitry. Channel Levellcue Rotary Controls: adjust individual input channel signal levels. Each channel can be cued by pulling the control knob outward to the detent position, rotating the knob to the desired level, and pushing the knob inward to activate 'the channel. Lo Cut Filter Slide Switches: reduce unwanted low-frequency signals such as wind noise by 6 dB per octave at 150 Hz. Master Rotary Control: determines mixed output level at out- put connector. The control also sets the tone oscillator level when the Tone Osc switch is turned on. Gated MemorylPeak LED: indicates, in gated memory mode, that gated memory is "holding" prior amount of compression during a low input signal, and turns off when input signal is above compression threshold. In peak mode, the LED indi- cates approaching program overload. It is activated by the shortest transient peak, but remains on long enough to pro- vide easy recognition. The chart below shows the effect of Compressor and Gated Memory switches on indicator opera- tion. GATED MEMORYIPEAK LED FUNCTIONS Gated Memory off I Gated Memory on Compressor out No operation Compressor in Gated memory VU Meter: indicates 0 VU with a +4 dBm output (recom- mended for normal use to provide approximately 14 dB headroom from operating level to clipping level) with VUlComp switch in VU position. Rear-panel VU Range +41+8 slide switch permits changing to 0 VU = +8 dBm. With VUlComp switch in Comp position, indicates compression due to input signal above threshold (lower meter scale). The VU meter is lit during ac operation only; therefore, the illumination serves as a visual alarm if the ac is interrupted and the unit has automatically switched to battery operation. Batt Check Momentary Push-button Switch: operates in con- junction with the VU meter to indicate battery condition. With the Power switch on and the switch depressed, a new set of batteries will give about a + 2 VU indication. Battery condition is good if the reading is above 0 VU; a lower reading means that new batteries are required for proper operation. Gated Memory Slide Switch: disables the gated memory function without affecting other operations. Response Rate Rotary Control: adjusts the compression system time constant to compensate for different types of pro- gram material. In general, a faster setting (toward the counterclockwise position) results in a more constant output level, but a more audible compression effect. Although the control setting is subjective, the following knob positions offer guidelines: speech -2; pop music -4; symphonic music- 7.

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Compressor Off-On Slide Switch: disables the compressor and gated memory functions, converting the FP51 to a stan- dard microphone mixer. Tone Osc Off-On Slide Switch: provides a highly stable, low- distortion 1 kHz tone for line tests and level checks. The tone signal level is controlled by the Master Level control. The tone signal appears on both the lipe and microphone outputs, as well as the Headphones and Mix Bus connectors. The tone oscillator should be switched off when not in use. Headphones 1M-inch Phone Jack and Miniature 3.5 mm Phone Jack: permit monitoring mixer output through most stereo headphones. The Headphones rotary control adjusts the out- put level of both jacks. Note that the headphones output level is high enough for use as an auxiliary unbalanced line feed to drive a tape deck or a power amplifier. lnput 1-4 XLR Connectors: are transformer-balanced, profes- sional three-pin audio inputs. Pins 2 and 3 are "hot" and "neutral," and pin 1 is ground. For microphone operation, the lnput MiclLine switches must be in the Mic position; for line level inputs, the switches must be in the Line position. Phantom Off-On Slide Switch: controls the application of phantom power for condenser microphones to all inputs. With the switch on and lnput MiclLine switches in the Mic position, +30 Vdc is applied to pins 2 and 3 of each input connector (power is automatically removed in the Line position). Series current-limiting resistance is 3.3 kilohms for each input. When using other than Shure microphones, verify that the voltage and resistance requirements are compatible. Output XLR Connector: is a professional three-pin audio con- nector for connection to either low-impedance microphone or line-level inputs of power amplifiers, mixers, or other signal- processing equipment. The Output MiclLine switch selects either microphone- or line-level output signals. Line Out Push Terminals: provide direct wire connection to a balanced 600-ohm line. Terminals are in parallel with the 3-pin Output connector when the Output MiclLine switch is in the Line position only. The red terminal is in parallel with pin 2 of the Output connector, and the black terminal is in parallel with pin 3. Note that the line-level output signal is always present on these terminals. Mix Bus Phono Pin Jack: provides direct access to the out- put channel mixing bus. This facilitates stacking or "multing" FP5ls to achieve additional input capacity without losing any inputs. With two FP5ls connected at their Mix Bus jacks, for example, the mix buses of each unit are directly connected, providing two independent Master gain controls and two isolated line amplifiers with eight individually control\ed in- puts. Since the buses are directly connected, a 6 dB drop in the gain of each output channel will occur, and the Master or In- put controls must be increased to compensate. Noise specifications are not adversely affected by this connection. INSTALLATION AND OPERATION Battery Operation In addition to 120- or 240-volt ac operation, the FP51 can be operated from an internal battery pack. Current drain is typically 30 mA at +4 dBm output level. Battery operation is recommended for remote, on-location operation, and as an emergency backup source in case of ac power failure. Access to the battery compartment is through the bottom of the chassis. Three 9-volt transistor radio batteries power the FP51 at full rated out~ut. Duracell MN1604 or Evereadv 522 batteries are recommended. Battery life is approximat~ly 10 hours at +4 dBm continuous use. Note that ~hantom Dower loading will increase battery drain. With batteries in the battery compartment, the FP51 will automatically and silently switch to battery operation should the ac voltage fall below a suitable level. Battery condition can be determined using the Batt Check switch on the front panel. With the FP51 Power switch on, ac- tivate the Batt Check switch and observe the VU meter. A new set of batteries will give about a +2 VU indication. Battery condition is good if the reading is above 0 VU; a lower reading means that new batteries are required for proper operation. Connections Connect the signal sources to the three-pin XLR lnput con- nectors. Connect the three-pin XLR Output connector andlor Line Out terminals to the input of a power amplifier, mixer, telephone line, etc. Set the Output MiclLine switch for the appropriate signal level. Refer to the Operating Hints section titled, Additional In- puts, for information on increasing the number of available microphone- or line-level inputs. Connect headphones to the phone jack or 3.5 mm mini phone jack, if desired, for monitoring the FP51 output. Connect the line cord to a 120 Vac 2 lo%, 50160 Hz source if the FP51 is to be ac-operated. If 240-volt ac operation is desired, refer to the Service section. Adjustments Turn the Compressor and Gated Memory slide switches on, the VUlComp switch to Comp, and the VU Range switch to + 4 or +8 dBm. Rotate the Channel Level and Master Level con- trols fully counterclockwise to 0, and set the Response Rate control for the program material to be used. If desired, turn on the Lo Cut Filter switches above the Chan- nel Level controls. The filter action will help reduce wind noise and undesirable low-frequency signals (see Figure 2). FREQUENCY IN HERTZ LO CUT FILTER ACTION FIGURE 2 Note that each input Channel Level control has a cuing capability. To cue a channel while the other channels are carrying program material, pull the desired Channel Level con- trol outward to the cue position. This removes that channel from the mixing circuitry and routes it only to the Headphones jacks. Adjust the Headphones level control to a comfortable listening level, and adjust the cued Channel Level control for a proper mixing level. Restore the cued signal to the program mix by pushing the Channel Level control inward. Turn on the Power switch and allow approximately 1 minute warmup time. The VU meter will light in ac operation. Turn the Phantom switch on if non-battery-operated condenser microphones are to be used with the FP51. (Caution: Do not turn the Phantom switch on when using unbalanced low im- pedance microphones.) Note that phantom power cannot be applied to the inputs with the MiclLine switches in the Line position; if line-level condenser microphones (such as Shure's SM82) are to be operated on phantom power, contact Shure's Service department for modification instructions. Turn on the Tone Osc switch. A dB compression reading of approximately 10 on the VU meter lower scale will result, and the Gated MemorylPeak LED will turn off. Set the VUlComp switch to VU and rotate the Master control for a 0 VU meter reading (upper scale). The tone signal can be heard in headphones connected to either phone jack. The tone signal can be used to calibrate equipment following the FP51. Reduce the Master control setting for a -2 VU meter reading, and turn off the Tone Osc switch. The Gated MemorylPeak LED will turn on, indicating that the gated memory is "holding" the prior amount of compression. Note the Master control setting for future use. (Note: This output reduction is made to compensate for the moderate short-term output dynamic range encountered for speech using the