Generally a mono spring reverb tank, though some schematics show it could be modified for stereo-like separation.
The schematic reveals a robust power supply, typically delivering roughly DC to the power sections.
To achieve true acoustic stereo blending, the JC-120 features . On vintage schematics, you will find two identical output stages, each featuring discrete complementary push-pull power transistors (such as the classic 2SD287 or 2SB539 transistors). Each power amplifier drives its own dedicated 12-inch, 8-ohm speaker. Troubleshooting and Repairing Using the Schematic jc-120 schematic
The JC-120 schematic has been widely used in various music equipment, including:
Print it out. Keep a highlighter nearby. Trace the audio path from the input jack to the speaker terminals. Once you understand why Roland placed a 330pF cap across the feedback loop of IC1B, you will understand why no modeler has fully captured the 3D depth of a real Jazz Chorus. Generally a mono spring reverb tank, though some
These may use surface-mount components and different power supply configurations. Accessing Schematics
This channel integrates the vibrato and chorus circuitry. The preamp on this side includes the distortion circuit and the input for the lush analog chorus. 3. The Chorus/Vibrato Circuit (The "Bucket Brigade") On vintage schematics, you will find two identical
Here’s a practical guide to finding, reading, and using the schematic.
To understand how this amp produces its legendary "Dimensional Space Chorus," we have to look under the hood at its unique dual-amplifier architecture and specific circuit components. 1. The True Stereo Secret: Dual Power Amps
