MPA201
MICROPHONE PREAMPLIFIER
Dual Channel Transformer Input/Output Coupled 100% Discrete Fully Balanced Microphone --Currently out of production; not filling new orders at this time.
The Ingram Engineering MPA201 provides two channels of semiconductor based 100% discrete two-stage amplification of microphone signals. Amplification is provided by all-discrete JFET input / Class-A Output circuits. This unit has a fully balanced design from input transformer to output transformer and has the highest voltage rails that will likely ever be encountered for a semiconductor design. A combined variable-attenuator/gain stepped switch control at the input provides the ability, unique among most pre-amp designs, of optimizing signal to noise and dynamic range for any audio signal level. A high current Class A buffer drives the output transformer.
Features
- Transformer Coupled Input
- Transformer Coupled Output
- Combined Attenuator / Gain Stepped Switch for Optimal Noise Performance and Dynamic Range Utilization (No Input 20dB Pad)
- 100% Discrete Design
- Two Stage Gain Structure, Each Stage with JFET input / Class-A Output
- High supply voltage for high headroom
- High Current Class A Output Buffer Stage
- Fully Balanced Signal Path, Input to Output
- 80 Hz 2nd Order High Pass Filter
- +48V phantom power
- Polarity reversal switch
- Clip Detector LED
- Continuously Variable Output Level Control
- External Power Supply
- Custom ETI noiseless level control pot with 10 million rotation life expectancy
- Long Life Panasonic Electrolytic Capacitors
- Polypropylene and Metallized Polyester Non-Electrolytic Capacitors
- 1% Metal Film resistors
Specifications
- Max Gain: 75 dB
- Frequency Response: 45kHz, ±3.0 dB, with Gain Setting = 0
- High Pass Filter -3 dB Cutoff Frequency: 80 Hz
- THD = 0.02% at +4dBu, 100k Ohm Load
- >+28dBu into 100 kOhms at 0.05% THD
- Overload level LED indication @ THD = 1% nominal, both positive and negative peaks, Overload circuit bandwidth > 30kHz