Maxon CS-550 STEREO CHORUS PRO

With a circuit based around the Panasonic MN3207 Bucket Brigade IC, the CS550’s “straight-outta ’79” chorus effect is bold and resonant without sounding harsh. Unlike the sterile chorus sounds of the 80’s, the 550 has an edgy, almost grainy quality that keeps your tone articulate and prevents wash-out.
The CS550’s custom-tuned oscillator circuit provides enough speed for authentic rotary speaker simulation, and just the right amount of modulation for a lush vibrato that won’t leave you feeling queasy.
With its Delay Time control the CS550 can venture into Flanger territory, adding a resonant, hollow quality to the effect that’s great for solos.
A rear-mounted Blend control allows you to adjust the level of the Chorus effect to set it back in the mix against your dry signal.
A unique feature of the CS550 is its ability to create spatial effects that add dimension to your guitar tone without the traditional Chorus wobble. With Speed and Depth set low and the Delay Time at max, the 550 thickens your sound much in the manner of a double-tracked guitar, adding girth and life without excessive modulation.
The CS550 features stereo outputs for mono, stereo, or inverted mono signal routing.

Tech Talk
The CS550 circuit is similar to the Arion SCH-1 Stereo Chorus, or an updated Boss Chorus Ensemble. A high-impedance input buffer passes next into a Compander stage that acts as a compressor/expander, bringing the input level of the signal up to an ideal output level and keeping it there as the signal decays – this provides a good signal-to-noise ratio and gives the chorusing section a nice, steady signal to modulate.
The Chorus effect is produced by a Panasonic MN3102 low-voltage clock driver IC and a Panasonic MN3207 BBD IC which is controlled by the MN3102.
The Delay Time control exhibits an inverse relation between the delay time and the frequency shift of the chorus – as the delay time increases, the frequency that is shifted decreases. This inverse relation creates “double level” and “cancellation” peaks and notches at particular frequency points to create an amazingly realistic, three-dimensional chorus effect. In addition, the Delay Time control is interactive with the Rate and Depth controls, so that if you increase the Depth, the Delay Time range increases, and if you increase the Speed, the Delay Time changes faster.
After the Chorus section, the signal hits another Compander to level everything out and is then fed to an output buffer.
At the end of the circuit the signal is phase-split and sent to the two low-impedance stereo outputs – Output A is in-phase and Output B is phase inverted (90 degrees out of phase).
The CS550features Mechanical True Bypass switching on both outputs via a Fujisoku 4PDT switch.