Aguilar OBP-3TK Förförstärkare/rackförstärkare

Aguilar OBP-3TK — Three-Band Onboard Bass Preamp with Selectable Midrange

The Aguilar OBP-3TK is a 3-band onboard bass preamp built for bassists who want studio-grade tone shaping directly from the instrument. Designed around Aguilar's most flexible onboard architecture, it offers high headroom and low distortion so the full dynamic range of the bass reaches the amp untouched. This model is the right choice for players upgrading a passive instrument or replacing a worn factory preamp with a circuit trusted by John Patitucci, Adam Clayton, and Paul Turner. Three dedicated pots and a mini-toggle for midrange frequency selection give players immediate, hands-on control over their core sound.

What Sets the Instrument Apart

Unlike stacked-pot configurations that cram two controls into one knob, this instrument ships with three separate Treble, Mid, and Bass pots for unobstructed real-time adjustment during a set. The included black mini-toggle switch flips the midrange center between 400Hz and 800Hz, letting players address either low-mid muddiness or upper-mid honk without rewiring. Operating voltage is selectable between 9V and 18V, giving installers flexibility based on available cavity space.

Three-Band EQ Architecture — Player-Facing Tone Control

The three-band EQ covers the full spectrum a bassist needs to dial in a signature sound, from sub-bass weight to treble articulation. Each band offers generous boost and cut range so players can both sculpt and radically reshape their instrument's voice.

• Bass Band: +/- 18 dB at 40 Hz — deep sub-bass control for adding weight or clearing muddiness at the lowest fundamentals
• Mid Band: +/- 16 dB at 400 Hz or 800 Hz — switchable center frequency targets either low-mid warmth or upper-mid presence
• Treble band adjustment provides +/- 16 dB at 6.5 kHz, which adds string articulation, finger noise detail, and top-end sparkle.

Power Supply and Wiring Flexibility

The preamp runs on either 9V or 18V, accommodating both compact control cavities and installations where maximum headroom matters. Aguilar ships detailed wiring diagrams for multiple use cases, so installers can configure master volume, blend, passive tone, and stacked bass volume layouts.

• Operating voltage of 9V or 18V allows for single or dual 9V battery operation, easily adapting to any control cavity.
• Included Controls: 3 × 50k potentiometers and a mini-toggle switch — everything needed for a standard install is in the box
• Wiring Options: Push/pull pot OR mini-toggle for midrange frequency selection — choose the layout that fits the instrument's control plate

Build Quality and Long-Term Reliability

The manufacturer backs this unit with a three-year limited warranty against defects in materials and workmanship, reflecting the brand's confidence in its preamp circuits. It has been in continuous production since August 2009 and remains a top seller in the bass electronics category.

• Warranty: 3-year limited warranty — covers original owner against defects in materials and workmanship
• Headroom: High headroom, low distortion — preserves the full dynamic range of the instrument

Who Should Install the Preamp

This preamp is the right choice for bassists who want professional-grade tone shaping without carrying a rack of outboard EQ. It suits players upgrading a passive Jazz or Precision bass, luthiers building custom instruments, and gigging musicians who need quick EQ adjustments between songs. The separate-pot layout works well for players who frequently tweak their sound on stage, while the mini-toggle midrange selection eliminates the need to dig into a push/pull pot mid-performance. Bassists using Nordstrand, Aguilar DCB, EMG, or similar aftermarket pickups will find this preamp pairs cleanly with most passive and active pickup configurations.

Aguilar's Heritage in Bass Electronics

Aguilar Amplification has built its reputation designing pickups, preamps, amplifiers, and cabinets specifically for bass players. The onboard preamp lineup — including the OBP-1, OBP-2, and OBP-3 families — has become a go-to choice for working bassists seeking aftermarket tonal upgrades.