dbx 286S Microphone Preamp

dbx 286s Microphone Preamp & Channel Strip — Studio Processing in One Rack Unit

This model is a full-featured channel strip processor that combines a studio-quality microphone/instrument preamplifier with four onboard processors — OverEasy compressor, frequency-tunable de-esser, enhancer, and program-adaptive expander/gate — that can be used independently or in any combination. The dbx 286s is the right choice for vocalists, podcasters, and home-studio engineers who want the entire microphone signal chain in a single 1U box with the shortest, cleanest signal path. Instead of patching together a separate preamp, compressor, EQ, and gate for one track, this instrument delivers the whole chain with detented, repeatable front-panel controls.

What Makes it Stand Out

Built around dbx's patented OverEasy compression topology, the 286s delivers the smooth, "in your face" vocal character that has defined the brand's processors for decades. The de-esser uses wideband gain reduction with a tunable high-pass filter from 800Hz to 10kHz at 12dB/octave, so engineers can dial in exactly where sibilance lives on a particular voice. The enhancer section pairs a bell-shaped boost at 80Hz with a simultaneous bell-shaped cut at 250Hz (roughly 2:1 ratio), cleaning muddy low-mid buildup while adding body to vocals and bass.

Microphone Preamp — Clean Gain for Any Condenser or Dynamic

The preamp section is the foundation of the entire signal chain, and engineers designed it to stay quiet even at high gain. Floating-balanced XLR input, switchable phantom power for condenser mics, and a switchable 80Hz high-pass filter keep rumble and wind noise out before any dynamics processing touches the signal.

• Mic Preamp Gain Range: 0 dB to +60 dB — enough headroom for low-output dynamics like the SM7B without an inline booster
• Phantom Power: +48 VDC — applied through 6.81 kΩ resistors on XLR pins 2 and 3 for safe condenser microphone operation
• Equivalent Input Noise (EIN): -125 dBu (22 Hz–22 kHz, 150 Ω source) — quiet enough for intimate vocal and voiceover work
• 80 Hz, 18 dB/octave is the high-pass filter setting that removes stage rumble, HVAC noise, and proximity-effect buildup before compression

Compressor & De-Esser — Vocal Dynamics Control

The OverEasy compressor and tunable de-esser sit between the preamp and the output stage, giving engineers two of the most-requested vocal tools in one place. Program-dependent attack and release times mean the unit reacts musically to performance dynamics rather than imposing a fixed curve.

• Compressor Threshold Range: -40 dBu to +20 dBu with OverEasy knee — soft-knee behavior for transparent level riding on vocals
• Compressor Ratio: >4:1 above threshold with up to 30 dB of gain reduction — enough control for both gentle leveling and aggressive broadcast limiting
• De-Esser Frequency Range: 800 Hz to 10 kHz — tunable to the exact sibilance band of the source voice

Enhancer & Expander/Gate — Polish and Noise Control

The enhancer adds air and body without the phase issues of a traditional EQ, while the expander/gate shuts the door on room noise, headphone bleed, and noisy guitar amps. Both stages are program-adaptive, so they react to the actual signal rather than a fixed envelope.

• Enhancer HF Detail: program-controlled shelving EQ, up to ~15 dB HF boost — adds sparkle and presence to dull vocal mics
• Enhancer LF Detail: bell boost @ 80 Hz, bell cut @ 250 Hz (~2:1) — adds warmth while cutting muddiness in one knob
• Expander/Gate Ratio: 1.5:1 to 10:1, max depth >50 dB — from subtle background-noise reduction to hard gating of amp bleed
• Power Consumption: 15 W — runs cool in a 1U chassis measuring 485 × 146 × 45 mm and weighing 2.04 kg

Target Audience

Podcasters, Twitch streamers, voiceover artists, and project-studio engineers need a complete vocal processing chain without filling a rack with separate units. Solo broadcasters running an SM7B or similar low-output dynamic benefit from the 60 dB of clean gain plus the 80Hz high-pass filter, while the de-esser and OverEasy compressor tame the peaks that cause listener fatigue on long-form content. Home-studio recordists tracking vocals and acoustic instruments get a single front-panel workflow with detented knobs that recall settings between sessions, and the insert jack lets users patch in an external EQ or delay without breaking the signal path. Live streamers benefit from the expander/gate killing background hiss from computers, fans, and open mics between sentences.