Based on equalizers found on historic EMI TG12345 recording consoles of the late ‘60s and early ‘70s. 
Mono Channel 
Discrete Transistor Circuitry 
Controls such as presence and bass bands, with continuous boost/cut, and true bypass. 
Presence band is switchable, featuring eight frequencies and an out position. The first seven frequencies are bell type, and the eighth is a shelf at 10 kHz. 
The bass band is a shelving type, featuring two frequency options, 90 or 150 Hz 
Handmade 
 
Format: 500-Series