Mercury M72s Dual-Channel Tube Microphone Preamp

The Mercury M72s is Mercury's flagship, dual-channel, valve studio microphone amplifier. The M72s is based on the most sought after vintage amplifier module — the Telefunken/Siemens V72s—which is most famous for being installed in REDD.37 consoles, used on all the early Beatles recordings by George Martin at Abbey Road Studios in London, England.

The Mercury M72s is based on the module used in consoles which are very rare due to a minimal amount made. The more common V72 amplifier modules (not marked with the lower case s, i.e. V72s) were later modified and have been sold for many years as outboard preamplifiers all over the world. Neither of these amplifier modules have been available new for more than 50 years. So, working units have become extremely rare, very expensive and in some cases are now in need of much repair. Regardless of cost, the uniquely musical tonal characteristics of these amplifiers has made them the prized possession of many engineers lucky enough to get the vintage modules, and a "secret weapon" for many studio musicians.

THE M72S IN DETAIL

The gain of the M72s is variable from 28 dB to 58 dB, in 3 dB increments, controlled with a high-quality rotary switch. Also, there is an option of a selectable input pad of -16 dB or -28 dB for even more control. Additionally, when the -28 dB pad is engaged and it is set at the lowest gain setting (28 dB) you can run signal through the M72s to add warmth and tonality to any tracks, mixes, keyboards, drum machines, samples, etc. There are also all the modern features including Phantom Power (on/off), phase (polarity) reversal, and an amazing sounding FDI (FET direct input) circuit per channel.

The FDI is a proprietary JFET circuit, based on a Class A tube topology. The Mercury FDI is designed to reproduce every nuance of a direct recording, while the circuit lets the tube or solid-state character of the amplifier determine the overall tone. The instrument DI signal is sent through the entire microphone preamp circuitry, including Mercury's custom, massive input transformers, so that the individual character of each preamp comes through.

The Mercury M72s has the rich lows and punchy mids giving you that 'instant' vocal tone, or assisting with a realistic acoustic guitar tone, punch to bass guitar. The same reaction to instruments or source as the vintage module but with slightly more open high end and openness. The M72s has that "vintage" tone and break up like the original circuit but it is a bit more musical over all (not cleaner, but more musical—there is a huge difference).

FEATURES:

• Mic input impedance: approx. 2k
• Suggested source impedance: approx. 200 ohms
• Input impedance with -28 dB pad: approx. 4k
• DI input impedance: 2M ohms
• Internal output impedance: 30 - 50 ohms (depends on gain setting)
• Suggested minimum load: 500 ohms
• Maximum mic signal input level (@20 Hz): +34 dBu with -28 dB pad engaged/+6 dBu with pad not engaged
• Maximum output level: +22 dBu
• Frequency response: 20 Hz to 20 kHz ±0.5 dB
• Harmonic distortion: All musically related low orders of harmonics, with no significant order above 5th