Wolff Audio RefPre

Ultra transparent 500 Series reference microphone preamplifier

• 500 Series fully transparent microphone preamplifier
• Transformerless design without signal coloration
• Up to 70 dB gain with dedicated Ribbon mode
• High headroom up to +28 dBu
• Extremely low distortion (0.0005%)
• Extended frequency response up to 80kHz
• Selectable 80Hz high-pass filter
• Relay-based controls for maximum reliability

Wolff Audio RefPre: reference microphone preamplifier without coloration

The Wolff Audio RefPre is a 500-series microphone preamplifier designed to offer maximum sonic transparency. Its goal is simple: to faithfully reproduce the source signal without adding any coloration. "Hear the mic, not the mic pre" is the philosophy behind this design.

With a minimalist, fully transformerless design, the RefPre ensures a clean and direct signal path, ideal for those seeking absolute precision in studio, broadcast, or high-end applications.

Transparent preamplifier with high headroom and maximum precision

With up to 60 dB of gain (70 dB in Ribbon mode), the RefPre is perfect for handling any type of microphone, including ribbon and high-output models. High headroom of up to +28 dBu ensures flawless performance even with dynamic and complex signals.

Extremely linear frequency response (±0.5 dB from 10Hz to 80kHz) and very low noise make this preamp ideal for critical recordings, sampling, and microphone modeling systems.

Maximum flexibility for studio, broadcast and audio production

The RefPre offers microphone, line and instrument inputs with dedicated selection, plus advanced controls such as phase inversion, phantom power with automatic muting and 80Hz high-pass filter. Ribbon mode includes a gain boost and automatic impedance adjustment with phantom protection.

All controls are relay-based to ensure reliability and consistency over time, making it an indispensable tool for professional studios and demanding sound engineers.

Ideal for modern microphones and emulation systems

The RefPre is particularly well suited for microphones that require maximum neutrality, such as modeling systems (e.g., Slate VMS) or high-precision microphones. Its transparency allows every detail of the source to be captured without alteration.

A true benchmark for those seeking absolute fidelity and uncompromising sound quality.

Technical Specifications.

• Format: 500 Series
• Type: Transformerless microphone preamp
• Gain: -10 dB to 60 dB (up to 70 dB in Ribbon mode)
• Step gain: 10 dB step rotary switch
• Trim: ±6 dB continuous
• Frequency response: ±0.5 dB (10Hz - 80kHz)
• Distortion: 0.0005% @ 60 dB gain
• Noise: -125 dBu EIN
• Headroom: +28 dBu
• Filter: 80Hz high-pass (12 dB/Oct) selectable
• Output fader: continuous from infinite to maximum
• Input: Mic (front/rear), Instrument Hi-Z front
• Mic/Inst selection: via dedicated switch
• Ribbon mode: +10 dB gain, impedance matching, phantom lockout
• Phantom power: 48V with automatic muting
• Phase inversion: selectable
• Indicators: green signal LED, red clip
• Controls: relay-based