Mxr Carbon | Copy Schematic

The sound is 98% the same. The topology hasn't changed because it works .

A top-mounted switch activates the modulation, which is further controlled by two internal trim pots . These adjust the modulation's width and speed , allowing users to fine-tune the "warble" from subtle chorusing to deep tape-like pitch shifts. Mxr Carbon Copy Schematic

Look at the schematic near the input jack. You’ll see a classic JFET op-amp (often a TL062 or similar low-power chip) configured as a non-inverting buffer. This gives you the standard 1MΩ input impedance that guitar pedals need. The sound is 98% the same

The schematic reveals a hybrid soul: