Mariupol Jazz Preamp

Mariupol Jazz Preamp is a noise-free, high-fidelity reimagining of the legendary Roland Jazz Chorus preamp section, specifically targeting the op-amp topology found in the stereo JC-77 and the James Hetfield-approved JC-120H head. While the original amps are iconic, they are a family of varied designs; we focused on perfecting the op-amp architecture by completely redesigning the circuit for the modern era. To eliminate the noise floor inherent in the vintage units, we downscaled the resistance values and replaced the standard 4558 chips with Hi-Fi-grade LM4562 op-amps for superior audio performance. We didn't stop there—the signal path is populated with high-quality film capacitors, even in the pico-farad range, a luxury never seen in mass-produced Roland amps. Powered by a custom modern switch-mode supply that boosts 9V to a massive 30V internal rail. Whether used as a pristine clean preamp, a boost, or a 4-band EQ with Fender-style interactive voicing, the added Hi-Treble control ensures your tone retains that crucial "spark" even at lower volumes.

• Bass / Mid / Treble - amp=style 3-band EQ.
• Hi-Treble - treble bleed control for additional spark in the tone.
• Volume - the gain of the preamp.
• LED brightness trimmer - placed on the PCB trimmer allows you to adjust the status LED brightness.

Power Supply: 9V DC adapter (Boss-style negative center) not included. No batteries. They are bad for the environment 🌲.

Don't try to power the pedal with voltages higher than 9V - this will damage the electronics. The pedal uses a chip to run the circuit on +-15V.

Voltage: 9V

Current draw: 120.0 mA

FREE 🌏 Worldwide shipping for orders over 100$ by Poland Post, courier shipping for orders over 350$. Check out our Shipping Policy for more details.

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Lifetime Warranty - feel free to contact us if you have any troubles with a pedal!