Royer Labs SF-2

A modern ribbon designed for acoustics, with the ease of an active microphone

Originally designed for classical and acoustic instruments, the SF-2 belongs to the family of ribbon microphones that prioritize timbral fidelity and smooth highs, while addressing a traditional ribbon microphone weakness: the need for a very high-gain preamp. Here, the integrated active electronics raise the output level, stabilize impedance matching, and provide a comfortable signal even with less "powerful" preamps, without losing the ribbon aesthetic (texture, depth, absence of harshness).

Who it's for and studio applications

The SF-2 targets sound engineers, demanding home studio users, and recording studios seeking a premium ribbon microphone capable of enhancing acoustic sources. It excels on string quartets, piano, acoustic guitar, delicate percussion, strings, and woodwinds, but is also very relevant on guitar amps, overheads, or room ambiance when a less "bright" image than a condenser is desired, with a sense of depth and naturalness.

Its bi-directional (figure-8) polar pattern enables creative techniques: two-sided recording (face-to-face duo), reduction of side leakage, or Mid/Side recording in combination with a cardioid microphone. Since the off-axis response is minimally colored, placement becomes more predictable: proximity effect, attack, and openness are simply adjusted by orientation.

Technical Specifications

Type and Design

• Operating principle: pressure gradient electrodynamic microphone with active circuit
• Element: aluminum ribbon (1.8 microns)
• Polar pattern: bi-directional (figure-8 response)
• Magnet: high-quality neodymium

Audio Performance

• Frequency response: 30 Hz - 15 kHz +/- 2 dB
• Sensitivity: -38 dBv (reference: 1 V/Pa +/- 1 dB)
• Self-noise: below 20 dB
• Maximum SPL: above 130 dB

Impedances

• Output impedance: 200 Ohms at 1 kHz
• Nominal load impedance: greater than 1.5 kOhms

Power and Connectivity

• Phantom power: +48 V required
• Output connector: 3-pin male XLR (hot: pin 2)

Dimensions and Weight

• Dimensions: 142 mm (length) x 39 mm (base) x 25 mm (height)
• Weight: 448 g

Technical specifications

Frequency response - start	30 Hz	Capsule	ribbon dynamic
Frequency response - end	15 kHz	Connection	XLR
Category	studio microphone	Color	Black
Directivity	bidirectional