The Heritage Audio '73 Junior API 500 Series Microphone Preamplifier Module is a 1U 500 series compatible 80 dB microphone and 10 dB line recording reproduction module based on the vintage 1073 designed by Rupert Neve. The remake is intended for recording engineers who want the classic Neve sound but do not need the equalizer functionality of the original module.
Using Styroflex and tantalum capacitors, the designers were able to fit all three 1073 discrete component Class A preamplifier gain stages in 1U of an API 500 Series lunchbox module.
The preamplifier supports selectable HI-LO minimum balanced and floating input impedances that accommodate a range of microphone types including vintage ribbons. You can also switch the module into line mode to re-amplify pre-recorded tracks and add color to a mix. Plugging in a mono 1/4" input into the DI port on the front of the unit automatically switches the module from MIC to DI mode. A discrete component Class A 3rd order 80 Hz high-pass filter with an 18 dB per octave slope has been added for recording sources without the effects of low-frequency coloration. An output control knob is included to prevent overloading the preamplifier.
The unit is powered by a +24V slow turn on power regulator that takes approximately 20 seconds to reach full voltage. This design improves the overall operation of your lunchbox PSU and makes the unit independent from the other modules in the lunchbox. To achieve the classic feel of the original 1073, the unit is constructed with Marconi-style knobs and vintage engraved pushbuttons.
HI: 1200 Ω minimum
LO: 300 Ω minimum
Line: 10 kΩ bridging, Carnhill transformer balanced and floating
DI: Greater than 2 MΩ, unbalanced
|Output Impedance||Less than 75 Ω,
Transformer balanced and floating to drive a load of 600 Ω
|Maximum Output||Greater than +26 dBm into 600 Ω|
|THD||Less than 0.025% at 1,000 Hz
Less than 0.05% at 100 Hz
|Frequency Response||20 Hz (+0.3 dB) to 20,000 Hz (-0.2 dB)|
|Maximum Gain||Slightly greater than 80 dB|
|Noise||Less than -100 dBm|
|Power Consumption||88 mA per rail at ±16 VDC|
|Dimensions (W x D x H)||1.50 x 6.89 x 5.32" (3.81 x 17.5 x 13.5 cm)|
|Weight||1.3 lb (0.6 kg)|