Both the API 3124+ and the 3124M+ are designed with the professional engineer in mind, giving the highest possible quality four-channel mic preamp and with the 3124M+, an audio mixer, while keeping the size and price at a reasonable level. Several 3124M+ mixers can be linked to increase the number of bussed channels. Both models are equally at home in the control room, the studio, and news or recording truck, at the house console, on the stage, direct-to-DAT or at the artist's disposal for the source of his music.
The model 3124+ utilizes the same microphone preamp circuit that is used in all API consoles. It uses the RE-115 K mic input transformer and the same output transformer that is used in all API equalizers. All four mic inputs of the 3124+ and the 3124M+ are powered by an internal 48 volt phantom power supply, front panel switchable for each channel. Also provided is a front panel 20 dB pad switch that effects both the mic and line in.
The model 3124+ can provide up to 65 dB of gain to an output clip level of +30 dBm. The Hi-Z front panel input goes directly to the op-amp, allowing a low level input such as a guitar or bass to be amplified without a matching transformer or direct box. This Hi-Z input can take input levels as high as +22, making it perfect for keyboards and other high level devices. The rear output is an XLR connector.
The model 3124M+ is a 3124+ with the addition of a complete stereo mixer. In conjunction with the gain control of the 3124+, the 3124M+ adds a stereo panner with a level control, and a post "fader" aux send. The stereo panners and the aux sends are bussed to master output controls and then to the rear panel jacks. A stereo AUX return is provided to return effects or cascade additional mixers for more inputs. The unique aux return pot acts like a panner to balance the left/right signal, yet staying stereo. It can also be used as a mono return. A standard 3124+ can be further expanded to an "m" at the factory. Several options for the "M" include a discrete unbalanced stereo output or a discrete balanced stereo output.