Check the listing for details. BLACKSTAR DEPT. 10 BOOST HIGH VOLTAGE CLASS A VALVE GAIN STAGE BOOST. Condition: New. Listed at 199.99 USD. BLACKSTAR DEPT. 10 BOOST HIGH VOLTAGE CLASS A VALVE GAIN STAGE BOOST *FREE SHIPPING* he Blackstar Dept. 10 Boost is a high-voltage valve boost pedal with a presence. Combining a Class A gain stage and natural-sounding passive James-Baxandall EQ, the Dept. 10 Boost brings the punch of adding two extra-hot valve stages to an amp. Dept. 10 is the Blackstar R&D team responsible for frontier-pushing innovation and design. Consisting of a group of engineers who are all also musicians, this team is focused on researching new ideas to help you create your ideal tone.ECC83 valve driven. Runs at 250V like a valve amplifier. Built-in buffer/line driver. James-Baxandall EQ: Low / High. Runs on 9V DC (PSU included). Compact design, stunning boutique style.