U-Turn Pluto Phono Preamp

Pluto is a low noise phono preamp for moving magnet (MM) cartridges. It combines high-quality components and elegant circuit design to accurately boost your turntable’s signal at this crucial stage of amplification. Pluto’s RIAA equalization network consists of WIMA film capacitors and precision resistors. It features a single high-performance gain stage and a subsonic filter to remove low-frequency noise – all housed within a steel enclosure that prevents interference. Assembled in Boston, MA.


  • Input impedance 47 kΩ
  • Input capacitance 100 pF
  • Gain 36 dB @ 1Khz
  • THD < 0.005% (A-weighted)
  • S/N ratio 90 dB (A-weighted)
  • RIAA accuracy +/- 0.2 dB (20Hz-20kHz)
  • Crosstalk -80 dB (20Hz-20kHz)
  • Dimensions 5.8 x 1.6 x 3.6″
  • Weight 0.9 lbs



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
Phono Stage:
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. (W) 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

Clearaudio Smart phono stage

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A step up from the Nano is the Clearaudio phono stage. Up to 54 decibels gain at one kilohertz. For MM and MC cartridges there are two separate circuit designs using SMD technology, which are selected by a slide switch on the underside. Loads and capacitance are adjustable. The Smart Phono Headphone V2 additionally contains a powerful headphone amplifier within the solid aluminium housing for private listening at the highest fidelity.http://clearaudio.de/en/products/electronics-smart_phono_v2.php

AMPLIFICATION @ 1 KHZ 54 – 68 dB (MC mode)
34 – 48 dB (MM mode)
INPUT IMPEDANCE 50 Ohm, 100 Ohm, 500 Ohm, 1 kOhm, 5 kOhm / 150 pF, 250 pF, 400 pF / MC mode
47 kOhm / 150 pF, 250 pF, 400 pF / MM mode
MM / MC INPUT switchable (at bottom)
SUBSONIC FILTER switchable (at bottom)
HEADROOM 18 dB / MC (Gain Control on MAX)
SIGNAL TO NOISE RATIO 72 dB / MC (“A” Weighted)
85 dB / MM (“A” Weighted)
CHANNEL SEPARATION > 90 dB @ 1 kHz / opposed channel hot-wired
POWER SUPPLY ± 18 V DC / 300 mA (external power supply)
TOTAL WEIGHT Approx. 600 gram (Preamp and power supply)
DIMENSIONS (W/D/H in inches) 3.74 x 4.92 x 1.34
DIMENSIONS (W/D/H in mm) 95 x 125 x 34