Specimen 431

SO-1200 (Shavo Odadjian Signature)

A 1,200-watt signature bass head with a real 12AX7 valve stage and two switchable 600-watt power sections.

Watch

PMTVUK's NAMM 2025 walkthrough takes a close look at the head itself, which is the most direct listen available for this model.

Why it matters

The valve preamp feeds a Class D output, making this a hybrid rather than a full tube rig. Two 600-watt sections let you run a full stack or a single cabinet without changing amps, and the design is based on Ashdown's existing ABM platform. A nine-band EQ, Variable Valve Drive and sub-harmonic generator give a lot of shaping ahead of the power stage.

Note

System of a Down bassist Shavo Odadjian's signature head, unveiled at NAMM 2025 and based on Ashdown's ABM platform. Dual 600-watt power sections drive multi-cab rigs, with a 12AX7 Variable Valve Drive, 9-band EQ and sub-harmonic generator.

Specifications

• 1200W (dual 600W sections)
• hybrid: 12AX7 tube preamp
• 9-band EQ
• Variable Valve Drive
• one-knob compressor
• Sub Harmonic Generator
• DI output
• FX loop
• 41 lb (18.6 kg)

Before you buy

• 41 lb / 18.6 kg — heavier than most Class D heads
• no cabinet included, so budget for one
• $1,999 list, and the valve drive is voiced for driven rock tones

Sources

• sweetwater.com
• notreble.com
• ashdownmusic.com