The JD9II is a versatile and affordable tube phono preamp. I heard one of these about three years ago and I was not personally impressed, but not only is that just my opinion, but I also feel there were mitigating circumstances such as an improperly set up turntable, which would blow everything. The company says they have improved the unit with a larger power supply, the addition a a robust voltage regulator, upgrade output capacitors and changes to the resistor arrays and has dim adjustments and two levels of output so you can easily configure the unit into your system.
Frequency Response: 5Hz to 110KHz, (+/- 1 dB)
SNR: > 100 dB
Distortion THD: Less than .01%
Input Impedance: 100Kohms
Output Impedance: 600 ohms
MM: 60 dB, 5 mV
MC High: 75 dB, 0.5 mV – 1.5 mV
MC Low: 85 dB, 0.25 mV – 0.5 mV
Input Resistance: 100 ohm, 300 Ohm, 1Kohm, 47Kohm
Input Capacitance 47 PF, 100PF, 150PF, 220PF
Tube Complement: 2 pcs. 12AX7
Size: 17 in. x 13 in. (D) x 2 in. (H)
Weight: 10 lbs.
Construction Details and Features:
Phono pre-amplifier that will handle MM, MC and Dynamic head cartridges.
Lowest Rated sensitivity at .25 mV – 85 dB.
Low noise -57 dB
Two Outputs RIAA, Line stage.
Adjustable settings for cartridge type