Warm Audio WA-MPX Microphone Tube Preamplifier

SKU: 1390
Warm Audio WA-MPX Microphone Tube Preamplifier
Warm Audio WA-MPX Microphone Tube Preamplifier
Warm Audio WA-MPX Microphone Tube Preamplifier
Warm Audio WA-MPX Microphone Tube Preamplifier
Warm Audio WA-MPX Microphone Tube Preamplifier
Warm Audio WA-MPX Microphone Tube Preamplifier

Warm Audio WA-MPX Microphone Tube Preamplifier

SKU: 1390
Regular price $749.00
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Injecting legendary tube warmth from one of the most formative eras of music history, the WA-MPX from Warm Audio is an authentic 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 (two 12AX7 tubes and one 12AU7), the WA-MPX 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-MPX features plenty of control over your input, including high- and low-pass filters, polarity selection, switchable +48V phantom, 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.


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-MPX authentically reproduces all the analog tone of the original to bring vintage warmth and color to your sound.


Three discrete, premium tubes 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, to richer distortion that can drive hard, the WA-MPX even outperforms solid-state preamps.


The WA-MPX 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 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.


In The Box

Warm Audio WA-MPX Microphone Tube Preamplifier

Limited 1-Year Manufacturer Warranty


Preamp Type Tube
Number of Channels 1
Phantom Power Yes
Polarity Switch Yes
EQ 80Hz highpass filter, 2kHz lowpass filter
Tubes 2 x 12AX7, 1 x 12AU7
Analog Inputs 1 x XLR, 1 x 1/4" TRS, 1 x 1/4" Hi-Z (front)
Analog Outputs 1 x XLR, 1 x 1/4" TRS
Frequency Response 0Hz-20kHz
Rack Spaces 2U
Power Source Standard IEC AC cable
Height 3.5"
Width 19"
Manufacturer Part Number  WA-MPX
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