Shure SCM810 manual

User Guide © 2006, Shure Incorporated 27A8868 (Rev . 1) Printed in U.S.A. SCM810/SCM810AZ SCM810/SCM810AZ EIGHT-CHANNEL MICROPHONE MIXER EIGHT-CHANNEL MICROPHONE MIXER[...]

2 DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3 SYSTEM FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 OPERATING PRINC IPLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . .[...]

3 DESCRIPTION The Shure Model SCM810/E is an eight-channel automatic microphone mixer designed for use in sound re inforcement, audio recording, and broadcast applications. The SCM810 dr amatically improve s audio quality in any application w here multiple microphones are re quired. Any low-im- pedance dynamic or condenser microphone (including wir[...]

4 FRONT PANEL FEATURES MODEL SCM810 FRONT PANEL FIGURE 1  Microphone Channel Gain Controls 1–8: Allows adjustment of microphone gain.  Input LED 1–8: Lights green when channel is active; lights red at 6 dB below clipping level.  Low-Cut Filter 1–8: Recessed screwdriver adjustment provides adjustable low-frequency rolloff (h igh pa ss[...]

5 DIP SWITCHES The rear-panel DIP switch provides the following setup options. The posi- tions shown in bold type are the factory settings. NOTE: Switch positions and effects are shown in Figure 3 and a lso on the mixer label. MODIFIABLE FUNCTION SWITCHES FIGURE 3 DIP SWITCH SW702 FUNCTIONS Manual/Auto: Automatic activation is defeated in the Manua[...]

6 INSTALLATION AND SYSTEM SETUP RACK MOUNTING THE MIXER T o mount the SCM810 in a st andard 483 mm (19-inch) audio equipment rack, slide the mixer into the rack and secure it with the supplied Phillips head screws, as shown in Figure 4. Use all four screws. RACK MOUNTING THE SCM810/E FIGURE 4 SCM810/E CONNECTIONS Make audio connections as follows ([...]

7 EQUALIZER FUNCTIONS Low Cut Filter (High-Pass) The low-cut (or high -pass) filter allo ws all frequencies above its cutoff point to pass from filter input to filter output without attenuation, while fr equencies below the cutoff are attenuated (see Figure 6). The cutoff point is defined as the frequency where the signal has dropped 3 dB relative [...]

8 NETWORKING MULTIPLE MIXERS If additional inputs are needed, more SCM810 mixers (as many as 50) can be “linked” using supplied link cables. Such a conf iguration can provide up to 400 microphone inputs. T o link multiple mixers, connect the LINK OUT of the first mixer to th e LINK IN of the next mixer , and so on (see Figure 8). Leave the LINK[...]

9 SPECIFICATIONS Measurement Conditions (unless ot herwise specified): Line voltage 120 V ac, 60 Hz (SCM810) or 230 Vac, 50 Hz (SCM810E); full gain; 1 kHz, one channel activated; source impedances: Mic 150 Ω , Line 150 Ω ; termina- tions: Line 10 k Ω , Phones 300 Ω ( tip- sle eve and ring-sleeve), Direct Out 10 k Ω ; Auto mode, equalization co[...]

10 ADVANCED FUNCTIONS LOGIC CONNECTION SPECIFICATIONS The logic functions of the SCM810 ex pand the mixer's range of inst allation and control options. Logic can be used for everything from simple cough switches to elaborate computer-c ontrolled room systems. (Shure's AMS Update publication contains additional appl ications of advanced lo[...]

11 SUGGESTED LOGIC APPLICATIONS This section contains suggestions on t he uses of the SCM810's logic capa- bilities. Note that uses of these func tions are not limited to the listed appli- cations. The user is limited only by individual imagination and creativity . For additional suggestions and solutions to installation problems, contact Shur[...]

12 Inhibiting Gating for Unwa nted Sounds As described in the Operating Principles section, MaxBus attempts to acti- vate only one microphone per sound source. Muting a microphone channel prevents its audio from appearing at the mixer's output. However , the mut- ed microphone still communicates with other mic channels via MaxBus. A sound sour[...]

13 Diode Isolation of Logic Controls T wo or more control functions using the same logic pins can be isolated with diodes. In this manner a chann el can be muted by an overall group mute switch, or by its own cough button (see Figure 19-Channels 1, 3 and 5 modified). DIODE ISOLATION OF LOGIC CONTROLS FIGURE 19 External Logic Devices SCM810 logic le[...]

14 INTERNAL MODIFICATIONS W ARNING: All modifications must be performed by qualified service tech- nicians. This section describes SCM810 modifi cations that can be made using sol- der “jumpers” on the printed circuit board; the pads where jumpers may be used are placed close together so that a single solder drop functions as a jumper . Note to[...]

15 SCM810 Speech Gate for Mixing Console The SCM810 can be used in conjunction with large mixing consoles to pro- vide automatic mixing for talk shows, panel discussions, and news shows. Large consoles have channel insert jac ks so that e xternal signal process- ing devices can be patched into individual channel si gnal paths. With this modificatio[...]

16 Increase Hold Time In addition to the dip switch SW702 options of 0.4- and 1.0-second hold time, the hold time can be increased to 1.5 seconds. (Mor e than 1.5 sec- onds is not recommended.) Procedure: Install a 470 k Ω resistor across jumper points X902. Move DIP switch down to 1.0-second position. Decrease Hold Time The hold time can be decre[...]

16 SHURE Incorporated http://ww w.shure.com United States, Canada, Latin America, Caribbean: 5800 W. Touhy Avenue, Niles, IL 607 14-4608, U.S.A. Phone: 847-600-2000 U.S. Fax: 847-600-1212 Intl Fax: 847-600-644 6 Europe, Middle East, Africa: Shure Europe GmbH, Phone: 49-7131-72140 Fax: 49-7131-721414 Asia, Pacific: Shure Asia Limited, Phone: 852-289[...]