Callisto is an all-tube line stage suitable for the most demanding audio systems and listeners. It is in the Jupiter Series (link to Jupiter Series description), sharing common design characteristics with the Io. It has won numerous awards, receiving worldwide acclaim for its superior sound quality.

• Fully balanced differential circuitry with ability to internally balance a single ended input signal.
• Innovative and unique mechanically switched discrete resistor volume control with 46 positions using Roederstein resistors.
• Separate volume controls and input selectors for each channel.
• All tube amplification and output (8 tubes total).
• Separate vacuum tube regulated power supply utilizing 8 tubes.
• Two sets of XLR and two sets of RCA outputs per channel.
• Six inputs: First two single-ended (rca) or balanced (XLR); remaining four single-ended (rca) only.

Callisto is available in three versions: Mk II, Signature and Eclipse.

The Mk II version uses high-grade Rel-Cap polypropylene coupling capacitors. The Signature version uses exotic and expensive coupling capacitors and other critical parts to bring the performance to a higher level. Eclipse is the ultimate realization of the true capabilities of the Callisto, incorporating constrained-layer damped machined aluminum panels and Peter Moncrief’s Stealth Capacitors. All versions of Callisto can be factory upgraded to Signature or Eclipse.

Callisto Options and Upgrades

• Signature Version Detail
• Eclipse Version Detail
• Callisto comes with a single power supply standard, or optionally a second power supply may be added for true dual-mono. Power Supply Detail
• Remote control is optional with the Callisto. Adding the system allows remote adjustment for volume and muting, and optionally phase. The remote system uses motors and pulleys to rotate the volume controls and has a completely isolated electrical system. It may be added to any version of Callisto. Remote Control Details
• Calliso Eclipse may be ordered with custom finishes. Design your own Callisto



Inputs: Six inputs: First two single-ended (rca) or balanced (XLR); remaining four single-ended (rca) only
Outputs: 2 RCA (SE) and XLR (balanced), 1 tape RCA
Line level gain: 23 dB single ended (SE), in/out, and 29 dB balanced/out
Volume control: switched resistor network volume control with 46 steps
Front panel controls: Left and right input select, left and right volume
Remote controls(optional): Volume, mute, balance, phase (option)
Frequency response: +- 0.25 dB, 20 Hz – 20 Khz
Signal to noise: measured at 70 dB minimum, A-weighted (ref 1 mv input, 75 dB gain setting)
Line input impedence: 100K ohms SE, 200K ohms balanced
Output impedence: 1K ohms SE, 600 ohms balanced
Recommended amplifier load: 10K ohms or greater (SE), 20K ohms or greater (Balanced)
Tubes, each channel: (line section) V1 (6922), V2 (12AX7), V3 (6922), V4 (6SN7)

Power consumption: 300 watts

Physical dimensions:
Main unit, MkII or Signature: 5 5/8″ high, 19″ wide, 18″ deep including jacks
Main unit, Eclipse: 5 1/2″ high, 17 1/2″ wide, 18″ deep including jacks
Power supply, MkII or Signature: 5 5/8″ high, 19″ wide, ” deep including jacks
Power supply, Eclipse: 5 5/8″ high, 17 1/2″ wide, 18 1/4″ deep including jacks

Shipping weights:
Main unit, MkII or Signature: 42 Lbs
Main unit, Eclipse: 47 Lbs
Power supply, MkII or Signature: 50 Lbs
Power supply, Eclipse: 55 Lbs