| 1-10 pieces $250.00 ea | 11-25 pieces $230.00 ea | >25 pieces $210.00 |
The Forssell Technologies JMP-1 is a fully functional Transformerless Microphone Preamplifier housed in a 2.5" x 3.6" x 0.5" potted module. The JMP-1 has a balanced DC coupled low noise input stage and a servo controlled single-ended output. All of the JMP-1's internal circuitry is fully balanced and DC coupled. Further there are no IC opamps, bipolar transistors, or coupling capacitors used in the JMP-1's main signal path. One high voltage IC opamp is used as a servo amplifier for the output stage. The JMP-1 uses only junction field-effect transistors biased for class A operation--No NPN or PNP bipolar transistors are used (Among other things, junction fet's do not have the problem with radio frequency interference that bipolar transistors do). The JMP-1 uses high quality surface mount components including Vishay, Holco, and Beyschlag metal film resistors.
The JMP-1 features low input noise (-129 to -131 dBu EIN, 22-22k w/50 Zs), wide bandwidth (-3dB @ 0.5 Hz and 650 Khz), fast slew rate (>60 V/us), and fast risetime (150 nanoseconds). The JMP-1 operates with a bipolar 24 VDC power supply (80 milliamps per polarity). Common Mode Rejection Ratios of over 100 dB are typical.
The JMP-1 can be used as either a transformerless microphone preamplifier, or as a summing amplifier for use with either balanced/differential or single-ended summing busses.
Gain range for the JMP-1 is 6-65 dB and is determined by a single resistor, switched resistor network, or a pot placed between the two gain control pins provided on the JMP-1 module.
The JMP-1 does not contain phantom power components, polarity reverse switching components, and/or differential output amplifiers within the module itself. These components can be added externally by the user/builder as needed or desired.
When used as a summing amplifier the JMP-1 can be configured as either a balanced or single-ended "virtual ground" (inverting) summing amplifier, or as a balanced or single-ended passive summing buss gain recovery amplifier. In any of these configurations the JMP-1 provide exceptional sonic performance and low noise operation. Sonically, JMP-1 summing amplifiers easily out perform IC opamp and IC/transistor hybrid summing amplifiers.