History of the CM-310A Handheld Differoid Microphone

The CM-300 was introduced June 1987.

The CM-310 was introduced Nov. 1988.
Compared to the CM-300, the CM-310 had:

• Lower noise
• Higher maximum SPL (151 dB)
• Lower current drain
• Smoother high end
• Warmer tonal balance

The CM-310A was introduced in Nov. 1994.
Compared to the CM-310, the CM-310A has:

• Better handling of powerful breath pops without cutting out or blocking
• A more streamlined, attractive grille
• A cleaner sound with reduced midbass

For more information:

White paper:
A High-Fidelity Differential Cardioid Microphone
Audio Engineering Society Preprint Number: 2713 Convention: 85 1988-11
Abstract: Many musicians need a handheld vocal microphone with superior gain-before-feedback and isolation from ambient sounds. A new differential cardioid microphone was developed to meet these needs without sacrificing fidelity. This paper discusses design goals, history of differential mics, and design implementation.

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