The API 3124+ is a discrete, high quality, compact, 4-channel mic/line preamp, plus D.I.
It is equipped with the RE-115 K mic input transformer and the proprietary API output transformer found in the 512c single mic pre and throughout the API product line. The unit has an internal 48-volt phantom power supply, which is switchable for each channel, as well as -20dB pad switches that affect both the mic and Hi-Z instrument inputs, both located on the front panel.
Another feature of the 3124+ is that it can provide up to 65dB of gain to an output clip level of +28dBu. Additionally, the Hi-Z front panel inputs feed directly to the op amps, which allow a low level input such as a guitar or bass to be amplified without a matching transformer or direct box. These Hi-Z inputs can take input levels as high as +20dBu, making them perfect for keyboards and other high level devices. The mic preamp outputs are on rear panel male XLR connectors.
Uses API 2520 Op Amps
Classic API console circuit
Four female XLR mic inputs
Four front panel 1/4" Hi Z instrument inputs
Front panel polarity switches
Front panel -20dB pad switches
Front panel mic/instrument switches
Front panel 48V power switches
Outputs clip at +28dBu
Input Impedance: 1500 Ohms Mic, 470 K Ohms Un-Balanced, HI-Z in Output Impedance: Less than 75 Ohms Channel Outputs Nominal Levels: XLR Channel Output +4 dBu
Stereo Output Level
Unbalanced: nominal -2
Clipping Level: XLR Channel Output better than +28 dBm Frequency Response: +0, -5, 10 Hz to 20 kHz (-.5 at 10 Hz) Noise EIN: -129 Mic, -125 Un-Bal. Actual
Measured Noise: Better than -91 dBm / below Nominal +4. Distortion: All Outputs at +4 out, .03%, at +22, .09% Max
150 Ohms Input 10 dB Min.
65 dB Max (inc. PAD)
Un-Bal. Input 14 dB Min.
50 dB Max
VU Meter: Calibrated for XLR Outputs, OVU=+4 dBu, (-12, -6, -3, 0, +3, +6, +18) Controls: GAIN, PAD (20 dB), 48Volts, POL (polarity), MIC (mic/un-bal), VU, AC Power Consumption, Quiescent: 19.2 Watts Size: 19" X 1.75" (1U) X 11" Deep Size (Boxed for Shipping): 23.25" X 6.5" X 16.5" Actual Weight: 10.38 lbs. Shipping Weight: 14.06 lbs.