[. . . ] AVALON DESIGN PURE CLASS A AD2022 DUAL MONO MICROPHONE & INSTRUMENT PREAMPLIFIER AVA L O N P URE C LASS A DESIGN M USIC R ECORDING S YSTEMS The AD2022 is Avalon's fourth generation of fully discrete, symmetrical Pure Class A microphone preamplifiers. [. . . ] The input signal selector, high pass filter, polarity-phase reverse, +48v power and the 20dB input attenuator all utilize local sealed silver relay operation. A variable passive high pass filter provides a minimum phase shift design while eliminating low frequency rumble, wind noise and mechanical vibration at sub sonic frequencies. SYMMETRICAL PURE CLASS A DESIGN Two 100% discrete, high-voltage, symmetrical Pure Class A signal amplifiers are utilized per channel. The first operates in a cascadedcascode FET configuration while the second stage amplifier is fully bipolar. This shared architecture increases the high level headroom capability, improves transient response and doubles the internal bandwidth of the ultra high performance Pure Class A signal amplifiers. OUTPUT and METERING High-current DC coupled, Class A discrete amplifiers are utilized for the output drive interface with +36dB capability into all known loads. [. . . ] Tel: 949-492-2000 Fax: 949-492-4284 Email: avalon@avalondesign. com www. avalondesign. com [. . . ]