Available in the following kits:

OBP-3TK: Includes separate Treble, Mid, and Bass pots,
and black mini-toggle switch for Midrange frequency selection.

OBP-3TK/PP: Includes separate Treble, Mid, and Bass pots. 
Mid pot is push/pull for Midrange frequency selection.

OBP-3SK: Includes stacked Treble/Bass pot, Mid pot, and black
mini-toggle switch for Midrange frequency selection.

OBP-3SK/PP: Includes stacked Treble/Bass pot and separate
Mid pot. Mid pot is push/pull for Midrange frequency selection.

OBP-3

The OBP-3 is Aguilar's most flexible onboard preamp design, providing +/-18dB of cut and boost at 40Hz, +/- 16dB of cut and boost at either 400Hz or 800Hz and +/- 16dB of treble cut and boost at 6.5 kHz. The OBP-3 has multiple wiring options, and can be wired with either a mini-toggle or internal dip-switch for midrange frequency selection.

Specs

Bass control: plus/minus 18 dB @ 40 Hz.

Mid control: plus/minus 16 dB @ 400Hz or 800 Hz. User selectable frequency center.

Treble control: plus/minus 16 dB @ 6.5 KHz.

Input impedance: 1 meg ohm

Output impedance: 100 ohm 9 or 18 volts operation. Additional 6dB with 18 volts.

Distortion: .019 into 10k ohm load

Noise: -95 dBm unweighted.

Battery life: 324 hours

Wire lead length: 6.50 inches

Low noise discrete FET input stage, center detent 50 K linear pots,with a dual concentric pot available.

Dimensions: 0.98"W x 0.98"L x 0.59"D

Warranty: Three year limited warranty.