Warm Audio WA-2MPX

The US manufacturer Warm Audio has earned a first-class reputation as a specialist in the successful reinterpretation of classic recording technology. The key elements of the original circuits are carefully replicated in each case on the basis of the respective prototypes and expanded to include useful extras, and the prices are surprisingly affordable as well. The Warm Audio WA-2MPX sees the Texas-based company stepping back into the golden era of Rock & Roll. This dual-channel microphone and instrument preamp is inspired by a legendary tape machine preamplifier from the 1950s and is Warm Audio’s first tube-driven device. Unlike the bulky prototype, which features just a single channel, the WA-2MPX comes in a compact 2U format and is equipped with everything that modern studio environments require.

The Warm Audio- WM-2MPX is a hand-built and fully discrete dual-channel preamp. Both channels are identically equipped and each feature three tubes and CineMag transformers. In addition to a full 90dB of tube power, each channel also features a switchable tape saturation control and a filter circuit to emulate the sound of tape machines running at a speed of 15IPS. This allows the WA-2MPX to deliver an authentic and powerful sound in duplicate with an exceptionally pleasing tone and natural-sounding compression. A 2kHz low-pass filter, 80Hz high-pass filter, and impedance switching permit extremely flexible sound configuration. Each channel has input and output sockets in both 6.3mm jack and XLR formats on the rear panel, and the front of the device is equipped with an additional instrument input per channel. Phantom power, a polarity switch, and a stylish dual VU meter round off the range of high-level features.

The use of high-quality and to a large extent authentic vintage technology allows the Warm Audio WA-2MPX to deliver distinctly characterful sounds. The 2MPX is the go-to wherever sufficient punch with a warm tone, or even extensive saturation, is required during the recording process. The powerful and, where required, even biting mid-range sound produced by the 2MPX makes it particularly suitable for signals typical in Rock music, such as electric guitar and bass guitar, but also the perfect device for drums, overheads, or even vocals. Warm Audio’s customary professional quality is on display in terms of both build quality and features here, and project and semi-professional studios alike wishing to add a veritable sound tool to their range of "all-rounder preamps" may also find the WA-2MPX attractive thanks to its comparatively low price.

As users have come to expect from Warm Audio, the manufacturer has expanded the essence of the original circuitry here to include a number of useful extra features. The WA-2MPX accordingly uses two 12AX7 tubes per channel (like the original) for the first amplifier stage and a further dual-triode tube (12AU7) for an additional 20dB boost, which is activated for each channel on the 2MPX and controlled by the gain control. The transformers are custom-made by the legendary US transformer manufacturer CineMag, once again to original specifications. By contrast, the filtering, tape saturation, and impedance switching features are found exclusively in the Warm Audio interpretation and considerably enhance the tonal flexibility of this dual-channel preamp.