Up for sale is 1 x Opamp Labs Model 103 low frequency inductor EQ kit (nine available) as found in one channel of the late 1960s Opamp Labs recording consoles:

1 - 103 Low Frequency EQ Kit (NOS) without black Raytheon control knob

These are a swinging input EQ as found in 1970’s API, Quad Eight and Sphere recording consoles. NOS sealed in bag. Faceplates can be supplied on request. Build your own console, or add a nice sounding inductor based

EQ to a custom preamp build. EQ points can easily be modified and expanded with different LCR values. These EQ kits work by connecting the EQ to the inverting/non-inverting inputs of an opamp like the Opamp Labs 325EQ amplifier pictured in the included schematic, but other

opamps will work with these EQ's as well. 

Feel free to let me know if you have any questions. Thank you!