API Audio: 3122V Preamp

The API 3122V 2-channel mic preamp is certainly not a new and revolutionary design, but rather a new version of a tried and true classic, originating in consoles from the late-'60s. This preamp circuitry is also in the 3124V 4-channel preamp, the 500 Series 312 [Tape Op #141], and shares most of the circuit design with the 312 and 512 series of preamps. All of these use the classic API 2520 op-amp and 2503 output transformer (some with a 3:1 output tap to drop the output and impedance level, allowing for higher gain/different tone). But why do we need yet another version of the same thing? Form factor. The standard 312 and 512 preamps are in 500 Series format, and the 3124V is a standard one-space, four-channel rack mount. But if you only need two channels in a single rack space, the 3122V shares all the features of the 3124V and adds a few more. Both of these preamps have output Level knobs (not found on all the 500 Series), allowing attenuation to drive the preamp harder, and buttons for Pad, Polarity reverse, and the 3:1 transformer tap. With only two channels of mic preamps instead of four, the 3122V has a little bit of extra real estate available, so we get some bonuses. There are two gloriously retro VU meters instead of smaller 7-segment LED meters, the addition of a front panel combo jack for either XLR or high-Z instrument input, and a 50 Hz high-pass (HP) filter. While these added features may not be “make or break” additions for some, I like that they included them on this unit.

Sonically, there aren’t any surprises. Although there have been minor circuit tweaks over the years, the basic building blocks of this mic preamp go back to the '60s. API is known for a clear and punchy sound, and the 3122V is no exception. The top end and midrange are where it really shines. That is not saying that the low frequencies are not well represented; they absolutely are. Remember, the API sound is a distinctly different character to the lower mid thickness of a vintage Neve-type preamp – slightly more aggressive, with seemingly faster transient response. When using the 3122V, I found that drums and electric guitars particularly benefit, sounding very “in your face.” However, it also shines on acoustic instruments, bringing an immediacy and sheen to the sound. I even used it on a classical piano recording with perfect results again, with clarity being the biggest sonic characteristic. This is not a revolutionary preamp, but it is a wonderful repackaging of a slightly evolved version of their classic mic preamp design in a new 2-channel form factor. For those who don’t have a 500 Series rack or don’t need four channels, this is a wonderful option that is the most cost effective way to get into the classic API preamps, in stereo!