Befaco InAmp
Dual instrument preamp for Eurorack integration
4 HP Eurorack module
The Befaco INamp is a dual-channel instrument preamplifier for Eurorack, designed to bring line-level and instrument-level signals (guitars, basses, microphones, pedals) into a modular system. Each channel features a variable gain stage built around inverting op-amp topology, allowing players to drive external sounds into Eurorack levels with character and control. The second channel can be optionally reconfigured as a send/return interface for external effects pedals.
Features
- Dual-channel instrument preamplifier
- Variable gain per channel via potentiometer
- 6.5mm (quarter-inch) jack inputs for guitars, basses, and line-level sources
- Minijack outputs compatible with Eurorack modular signals
- Minijack inputs on control boards for inter-board signal routing
- Two TL072 op-amps in inverting amplifier configuration
- Two 2N3904 transistors (Q1, Q100) for signal conditioning
- Per-channel LED signal/power indicator
- Ferrite bead power filtering for clean power supply rejection
- Schottky diode (1N5817) reverse polarity protection
- Second channel reconfigurable as send/return effects loop via PCB jumper modification
- Three-board design: one main board plus two control boards
Controls & Jacks (10)
- Gain 2 — Gain control for channel 2
- Gain 1 — Gain control for channel 1
- Output 1 — Amplified audio output for channel 1
- Output 2 — Amplified audio output for channel 2
- Input 1 — Audio input for channel 1
- Input 2 — Audio input for channel 2
- ctrl_007
- CV Input 1 — Control voltage input for channel 1 gain modulation
- CV Input 2 — Control voltage input for channel 2 gain modulation
- ctrl_010
How-To Guides
- Guitar Into Modular
- External Pedal Send/Return Loop
- Dual Instrument Preamp
- Dynamic Microphone Into Modular
- Hot Oscillator Level Matching
- Guitar Through Modular Filter Sweep
- Bass Triggering Envelope Follower
- Stereo Line Level to Modular
- Custom Gain Response via Resistor Swap
Explore the interactive InAmp panel on BleepDex — tap any control to learn what it does.
