Details:
PCB size: 110X76MM
Power supply voltage: AC12VX2 to AC20VX2
Op amp options:
NE5532, low frequency and thick warmth, more classic
OPA2111, delicate, good voice, excellent positioning
49720NA, AHP, better distortion
Package included:
Dual preamplifier board pcb x 1
Not included any parts !
Assembled board ,just for reference: