Wolff Audio RefPre

The Wolff Audio RefPre is a premium 500 Series reference preamp designed for pure, uncolored sound reproduction. Built with minimal circuitry and a transparent signal path, this preamp ensures that your recordings capture the truest representation of your microphone and instrument sources. Whether you're working with high-output condenser microphones, dynamic mics, or delicate ribbon microphones, the RefPre offers exceptional headroom and precision. Originally developed for the Wolff Console, it boasts 60dB of gain, with an additional 10dB boost in Ribbon Mic mode, along with auto impedance adjustment and phantom power lockout for added safety.

This preamp is an excellent choice for professional recording studios, broadcast environments, and engineers who demand the highest fidelity. Features such as a switchable polarity reverse, 48V phantom power, an 80Hz high-pass filter, and relay-based gain adjustments provide flexibility and reliability. The front-panel instrument input with a dedicated Hi-Z input amp makes it versatile for both mic and line-level sources. With a frequency response of 10Hz to 80kHz (±0.5dB), ultra-low distortion (0.0005% at 60dB gain), and high headroom (+28dBu output), the RefPre is perfect for applications requiring accuracy, from emulation microphones like the Slate VMS to instrument miking with Earthworks and Neumann models.

• Transparent Sound " No added coloration; preserves the natural audio signal.

• High Accuracy & Headroom " Handles various mic types, including high-output and ribbon microphones.

• Ribbon Mic Mode " Adds 10dB of gain, adjusts impedance, and locks out phantom power for safety.

• Switchable +10dB Gain Boost " Provides additional headroom when needed.

• Adjustable Output Fader " Smooth control from silent to full output.

• 80Hz High-Pass Filter " Removes low-frequency noise for cleaner recordings.

• Polarity Reverse Switch " Quick phase correction for better mix alignment.

• 48V Phantom Power " Momentary signal mute during switching for safety.

• Relay-Based Controls " Ensures precise, reliable adjustments with repeatable gain settings.

• Front & Rear Inputs " Convenient access for microphones and instruments.

• Hi-Z Instrument Input " Dedicated input with a MIC/INST selector switch.

• LED Signal Indicator " Green for signal detection, red at +18dBu (10dB below clipping).

• Low Noise & Distortion " Ultra-low noise floor and high-fidelity sound reproduction.

GENERAL FEATURES:

• Transparent preamp design with minimal circuitry and signal paths

• Designed for accuracy with extra headroom for various microphone types, including high-output and ribbon microphones

• Ideal for mic, line, and instrument preamp applications

GAIN & SIGNAL PROCESSING:

• 60dB gain with a stepped rotary switch (10dB increments)

• Ribbon mic mode: Adds 10dB gain, auto impedance adjustment, and phantom power lockout

• +/-6dB Trim Control for precise gain adjustment

• High headroom output: +28dBu

• Low noise and distortion: -125dBu EIN and 0.0005% distortion at 60dB gain

INPUT & OUTPUT:

• Front & back panel mic input access

• Front panel Hi-Z instrument input with dedicated Hi-Z input amplifier

• Selectable input source (MIC/INST switch)

• Polarity reverse switch

• Continuous output fader (INF to full output)

FILTERS & INDICATORS:

• Switchable 12dB/octave 80Hz high-pass filter

• Signal indicator LED: Green (signal present), Red (flashes at +18dBu, 10dB below clipping)

POWER & SWITCHING:

• 48V Phantom power with momentary output muting during switching

• Relay-based gain adjustments and switching for improved reliability

• Transformerless microphone preamp design