General
The Models 315 and 315S are compact and rugged rib­bon mics combining wide range response and a bidirec­tional pickup pattern. The bidirectional pattern reduces noise and reverberation providing the same control as an equivalent cardioid microphone. The Models 315 and 315S are ideal for high-quality public address, theater stage sound systems, and recording applications. Due to the bidirectional polar pattern, they may be used for either single performer, a dialogue or group, solo or orchestra, and other individual or chorus applications.

Specifications in other respects are the same as for the standard models.

Microphone Features

• Wide-range front and rear response
  
  
• Bidirectional polar pattern, effective
  over wide frequency range
  
  
• Convenient impedance selection
  
  
• A strong detachable cable especially selected
  for good shielding from “hum” pickup
  
  
• A self-adjusting swivel permits aiming
  microphone at source of sound
  
  
• Rugged mechanical design with
  special ribbon protection

The Models 315 and 315S are multi-impedance for con­necting into mic inputs rated at 25 to 50 ohms, 150 to 250 ohms, or into high-impedance mic inputs. The low impedances are recommended where long cable lengths are required or under conditions of severe hum dis­turbance. Cable length is almost unlimited, since neither response nor level is appreciably affected. For use with high-impedance amplifiers, the Shure Model A95UF Line-Matching Transformer is available for coupling the low impedance line to the amplifier input.

Impedance Selection
Selection of the various impedances is accomplished by removing a plate and changing the position of the switch at the rear of the microphone. The switch positions are marked “L” for low impedance (25-50 ohms), “M” for medium impedance (150-250 ohms), and “H” for high im­pedance (35,000 ohms).

• Frequency response: 50 to 12,000 Hz (see Figure B)
  
  
• Polar Pattern: Bidirectional, equally sensitive at front and back. Response at sides down 15 to 20 dB from front and rear responses (see Figure C)
  
  
• Switch: Model 315 none
  
  
• Case: Chrome-plated die cast
  
  
• Net Weight: 1 pound (454 grams)