Model SCM268 User Guide MASTER 1 2 3 AUX IN 4 VE OUTPUT LE -20 icrop SCM268 m hone mixe -10 0 LMETER +6 +12 +18 POW ER r Four-channel Microphone Mixer ©2003 Shure Incorporated 27D8646 (Rev. 4) Printed in U.S.A.
! IMPORTANT SAFETY INSTRUCTIONS ! 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 2 READ these instructions. KEEP these instructions. HEED all warnings. FOLLOW all instructions. DO NOT use this apparatus near water. CLEAN ONLY with dry cloth. DO NOT block any ventilation openings. Install in accordance with the manufacturer's instructions. DO NOT install near any heat sources such as radiators, heat registers, stoves, or other apparatus (including amplifiers) that produce heat.
SHURE SCM268 DESCRIPTION With the supplied hardware, the mixer's half-rack chassis mounts securely in single or dual rackmount installations. For fixed installations, the SCM268 can be fastened on or below a shelf, counter, or tabletop.
GAIN CONTROL ENGLISH INPUT GAIN OUTPUT GAIN The gain control knobs 1-4, located on the front panel, adjust the gain for both microphone and auxiliary-level inputs of channels 1-4 (see Figure 1). For example, the channel 1 gain control is used for both the channel 1 microphone input (MIC LEVEL INPUT 1) and the channel 1 auxiliary level input (AUX LEVEL INPUT 1). The auxiliary gain control knob (AUX IN) affects only the auxiliary input (AUX IN).
CONNECTIONS The following diagram illustrates a few of the many types of connections possible with the SCM268. Note that nothing is connected to the channel 4 microphone input (MIC LEVEL INPUT 4). This is because channel 4 is being used for the consumer-level equipment connected to the channel 4 auxiliary level input (AUX LEVEL INPUT 4).
INSTALLATION ENGLISH SUPPLIED HARDWARE 2. • • 4 rubber feet. For stand-alone installation. 1 rackmount bracket, long. For half-rack (single unit) installations. • 1 rackmount bracket, short. For half-rack (single) or dual-mount installations. 2 straddle brackets. For dual-mount or fixed installations. 12 bracket screws, 1/4 in. (6 mm). For securing the brackets to the chassis. 4 rackmount screws, 1 in. (2.5 cm). For mounting the unit in a rack. 4 plastic washers.
INTERNAL MODIFICATIONS WARNING! Voltages in this equipment are hazardous to life. No user-serviceable parts inside. Refer all servicing to qualified service personnel. DISASSEMBLY The following table lists the low-cut frequency corners for some of the most common capacitor values: Capacitor Value (mF) .033 .047 .068 .1 .22 .33 .47 .68 1.0 2.2 PHANTOM POWER DISABLE KNOB ASSEMBLY FIGURE 2 3. 4. 5.
SPECIFICATIONS ENGLISH Measurement Conditions (unless otherwise specified): Line voltage 120 Vac, 60 Hz (SCM268) or 230 Vac, 50 Hz (SCM268E); full gain; 1 kHz, one channel activated; source impedances: Mic 150 W, Aux Level 150 W; terminations: Line 600 W, Mic 600 W, Aux Out 10 kW. 12 V phantom power off.
SHURE Incorporated Web Address: http://www.shure.com 5800 W. Touhy Avenue, Niles, IL 60714-4608, U.S.A.
