The Warm Audio WA-412 4-channel Microphone Preamp is a four-channel preamp for microphones and Hi-Z inputs housed in a 1 RU chassis. It's fashioned in the American console preamp style, providing a punchy bottom end and smooth trebles. Each channel gives you 65 dB of gain, polarity switching, a 20 dB pad, 48V phantom power, a switchable impedance selector for tonal shaping, and knobs for both input gain and output; this allows for both precise and creative gain structuring of sound. You can easily watch your signal via the on-board LED meter for every channel.
Under the hood, you'll notice that each channel uses a discrete and socketed 6-pin X520 op-amp, which helps in giving you a significant amount of headroom with minimal distortion characteristics. You'll also note the Altran input and output transformers. If you don't peak under the hood, you'll take comfort in the fact that these components are extending your low-frequency response all while maintaining a pleasurable and open sound.