The PrimaLuna ProLogue Two is the KT88-powered integrated in PrimaLuna's ProLogue range, built around a simple idea: give people the sound of a hand-built tube amp without the maintenance headaches that usually come with one.
Design & Engineering
The ProLogue Two delivers 40 watts per channel in ultralinear operation from a quartet of KT88 output tubes, driven by 2x 12AX7 and 2x 12AU7 small signal tubes. The whole amplifier is point-to-point hand-wired onto a heavy-gauge steel chassis finished to automotive standards, with custom-designed output transformers and a toroidal power transformer.
The standout feature is PrimaLuna's Adaptive AutoBias. The circuit monitors and adjusts bias continuously, cutting distortion by 40 to 50 percent compared to conventional designs. In practice it means no matched tubes required and no bias adjustments, ever. It also lets you roll in other output tubes, including 6550, KT90, EL34 and KT77, without touching a screwdriver.
Supporting all of this: a soft-start circuit for gentle warm-up, tube plate fuse protection, and premium parts throughout, including Solen and Nichicon capacitors, an Alps potentiometer, WBT speaker terminals and gold-plated jacks. A removable tube cage is included.
Technical Specifications
- Type: Integrated valve amplifier, ultralinear
- Power Output: 40W per channel
- Tubes: 4 x KT88, 2 x 12AX7, 2 x 12AU7
- Frequency Response: 20Hz–30kHz (±0.5dB)
- THD: <1% at full power
- Signal-to-Noise Ratio: 89dB
- Input Impedance: 65k ohms
- Inputs: 4 x RCA
- Speaker Outputs: 4 and 8 ohms
- Dimensions: 11" W x 7.5" H x 15.5" D
- Weight: 37.5 lbs