JM-530 500 Series Preamp
Price: $750.00
S/H:  $12.50M
Total:  $762.50

JMK Audio  are now using the SonicImageryLabs 990Enh Op Amp.

JM-130/JM-530 Features not found on most other mic pres:

Very high Input headroom: for a very wide Dynamic range, ov er 131dB for the JM-130, >128dB for the JM-530.

The Pad is on the output: this has several advantages; One it does not affect the loading and sound on the mic, Two; Since No DC voltage goes thru the switch (Phantom) like most Mic pre pad circuits on other mic pres there is NO pop when the switch is engaged. Third; being on the output allows the output transformer to be driven harder for a warmer sound.

(JM-530) Added Brass thumb screw to aid in removal or installation of JM-530 Module into Lunch Box. (See Bottom Picture)

The Phantom switch: the phantom voltage ramps up to reduce the pop when powering a Condenser mic.

All switches on both the JM-130 & JM-530 are the large Gold plated switch, to provide very long life and improve the clarity of the signal path, and greatly reduce the probability of noise and static.

  • Jensen JT-16B Input Transformer
  • Very high headroom & Wide Dynamic Range
  • Input Impedance: 1.6K @ 1Khz
  • Output Transformer Option: Nickel or Steel
  • Hand wired point to point
  • THD+N:   .006% @50dB Gain @ 1Khz
  • .025% @-5dB In @ 50Hz
  • .044% @ +5dB In @ 50Hz
  • .0125% @ 0dB Input @ 100 Hz
  • .025% @ +10dB Input @100Hz
  • .007% @-10dB Input @15Khz
  • 990 Op Amp Slew Rate: 18Vus @ 150 Ohm Load
  • Frequency response: +- 1dB 10hz to 170khz ; +-.25dB 10 to 50Khz
  • Max Gain: -3dB @174Khz.
  • 990 Op Amp Only: +-1dB 5Hz to 500Khz
  • Output clips at +32dBu
  • CMRR: 117dB @ 60Hz, 85dB @ 3Khz
  • E.I.N. Noise: -128.5dB w/ 20 to 20kHz filter w/150 ohm load @62dB Gain
  • -127dB W/20 to 20KHz Filter W/300 ohm load @62dB Gain
  • Dynamic Range: >128dB; 20 to 20KHz filter w/150 ohm load @ min gain
  • > 105dB; 20 to 20KHz filter w/150 ohm load max gain
  • Maximum Input: +8dBu
  • Gain: 62dB
  • Hand selected .1% Phantom Resistors
  • Pad: 8dB on output, enabling the output transformer to be driven harder.
  • Phantom switching: voltage ramps up to reduce popping with condenser mics.
  • Laser Engraved lettering, letters will not wear off.
  • Note: 20 to 20 kHz filter used; -10dB @ 38 Hz & 32 KHz, -20dB @ 90 KHz
    Far wider than the typical Brick wall filter, which is -20dB @36Khz