Old School is Now in Session

Injecting legendary tube warmth from one of the most formative eras of music history, the WA-2MPX from Warm Audio is an authentic 2-channel reproduction of the preamp used in the AMPEX 351 tape machine, a history changing microphone pre used by such famed artists as Les Paul, Elvis Presley, Nat King Cole, Roy Orbison, and more. Sporting three warm vacuum tubes per channel (two 12AX7 tubes and one 12AU7), the WA-2MPX delivers up to 90 dB of exceptionally clean gain, including a further 20 dB high-gain boost for low-output sources, and exudes vintage style with its brushed aluminum faceplate and Bakelite-style knobs.

The WA-2MPX features plenty of control over your input, including high- and low-pass filters on each channel, polarity selection, switchable +48V phantom power per channel, tone control for changing impedance and applying color, and selectable tape saturation to add harmonic distortion and natural compression to your signals. The custom-wound large-core CineMag transformer provides reliable performance and helps to deliver the vintage-inflected tone sought by so many modern artists, from Mark Ronson and John Mayer, to St. Vincent and Amy Winehouse.

Legendary History

Les Paul changed the course of music forever by inventing reel-to-reel tape recording using a preamp made by AMPEX, which would eventually become part of the 350 and 351 model tape machines. This tube preamp pioneered the birth of rock 'n' roll and many radio hits, with a signature tube warmth defining a legendary era of music that is still chased today. With premium components, true-to-original circuit design, and tape-saturation control, the WA-2MPX authentically reproduces all the analog tone of the original to bring vintage warmth and color to your sound.

Better Than a Plug-In

Three discrete premium tubes per channel paired with custom transformers result in a vintage analog tone that digital circuits and software plug-ins simply can't touch. And with the ability to go from a clean volume for quieter sources, like ribbon and low-output dynamic mics and richer distortion that can drive hard, the WA-2MPX even outperforms solid-state preamps.

Control Your Tone

The WA-2MPX provides plenty of options for controlling your signal. Knobs allow you to adjust input source (mic, line, or instrument), preamplifier gain (up to 90 dB), and output level. There are switches on each channel for changing microphone polarity/phase, a high-gain boost of an additional 20 dB, +48V phantom power, and tone, which alters the input impedance to inject color into your signal. You also get an 80 Hz high-pass filter, a 2 kHz low-pass filter, and tape saturation for adding nonlinear, harmonic distortion reminiscent of a tape machine at 15 ips.

Favored by Artist New and Old

This classic circuit design has driven countless hit-making records from the '50s to the modern era. Steve Albini, a known 351 fan, acquired several 351s in 1996 for use in his world famous Electrical Audio recording studio, and many more modern producers and recording artists have used this equipment to achieve an iconic sound that only a true tube preamp can achieve.

Original AMPEX 351 Artists:

• Les Paul
• Elvis Presley
• Bing Crosby
• Nat King Cole
• Roy Orbison

This sound is also chased by modern artists such as:

• Jack White
• Black Keys
• Amy Winehouse
• Mark Ronson / Bruno Mars
• John Mayer
• The 1975
• St. Vincent
• Arctic Monkeys

In the Box

• Warm Audio WA-2MPX Stereo Microphone Tube Preamplifier
• Limited 1-Year Manufacturer Warranty