The DBX 160 Compressor

dbx 160 vu compressor

The DBX 160 didn’t just control dynamics—known for its precision, punch, and simplicity, this box reshaped the sound of recorded audio.

History of the DBX 160 Compressor

The DBX 160 Compressor stands as one of the most influential pieces of dynamics processing hardware ever made. Introduced in the mid-1970s, it marked a major shift in how compression was handled in professional studios. Instead of relying on opto or FET circuitry, the DBX 160 used a true RMS detector and a voltage-controlled amplifier (VCA), offering a more consistent and musically transparent response. Designed by David E. Blackmer, founder of dbx Inc., it was based on his patented “Blackmer gain cell” — a circuit that became a cornerstone of modern VCA compressor design.

Early Development and Foundations

dbx Inc. was founded in 1971 by David Blackmer, an audio engineer focused on improving fidelity through wider dynamic range. Before the 160, dbx was known for its noise reduction systems, which used the same core principle of dynamic range control. The company’s research into RMS-based compression eventually led to the creation of a standalone unit that could apply precise, musically responsive gain reduction without coloration or distortion.

In 1976, the original DBX 160 — often referred to as the 160 VU — was released. It was a half-rack mono compressor with two large VU meters and a feed-forward design. This architecture allowed the compressor to “look ahead” at the signal, responding quickly and accurately without the sluggishness found in feedback-based compressors of the time.

Design Characteristics and Technical Innovations

The defining feature of the DBX 160 was its use of the RMS detection method. Unlike peak-based systems that react to instantaneous levels, RMS detection responds to the average power of the audio signal, creating smoother, more natural compression. The VCA, built around the discrete Blackmer gain cell, was capable of handling high dynamic ranges while maintaining very low distortion.

The 160’s “hard knee” response curve was another hallmark of its design. Rather than easing into compression, it would clamp down abruptly at the threshold, resulting in a distinct and controllable punch. Later versions would introduce a “soft knee” option known as Over Easy, first seen in the dbx 165 and later incorporated into the 160X.

Evolution Through the 1980s and Beyond

The success of the original 160 led to several refinements. As component technology advanced and studio standards changed, dbx adapted the design while keeping its sonic character intact. The 160A, 160X, and 160XT became staples in professional and project studios worldwide, with each iteration improving reliability, consistency, and connectivity.

While the original model was built with discrete components, later units incorporated integrated circuits for improved manufacturing and serviceability. The essence of the design, however — RMS detection feeding a VCA gain stage — remained unchanged.

Timeline of the DBX 160 Series

  • 1971: David Blackmer founds dbx Inc., focusing on expanding dynamic range and reducing noise.
  • 1976: The original DBX 160 (also known as the 160 VU) is introduced, featuring discrete VCA and RMS circuitry.
  • Late 1970s: dbx releases the 161, a consumer-oriented variant with similar architecture.
  • Early 1980s: The DBX 160X and 160XT are introduced, adding Over Easy soft-knee compression, LED metering, and stereo linking.
  • 1989: The DBX 160A arrives, combining modern components with the classic circuit topology and improving build consistency.
  • 1990s–Present: Various reissues and modern updates continue, keeping the DBX 160 design alive in both analog and digital forms.

Software Emulations

  • Waves DBX 160 Compressor/Limiter Plugin
  • UAD DBX 160
  • Native Instruments VC 160
  • Arturia Comp VCA-65 (inspired by DBX VCA topology)
  • Softube VCA Compressor

Tips and Techniques

  • Start with Light Gain Reduction

    Begin with the threshold set just where the gain reduction meter starts to move, typically 1–3 dB. The DBX 160 responds quickly, so small adjustments go a long way. Starting conservatively lets you hear the compressor’s natural tone before dialing in stronger control.

  • Understand the Hard Knee Character

    The original DBX 160 is a hard-knee compressor, meaning it clamps down suddenly once the signal crosses the threshold. This gives drums, percussion, and transient-heavy sources a sharp, controlled edge. Use it when you want firm, defined control rather than smooth leveling.

  • Try “Over Easy” for Smoother Control

    Later models like the 160X, XT, and most plugin versions include “Over Easy” mode, which softens the transition into compression. Use this on vocals, bass, or acoustic instruments when the original’s hard-knee behavior feels too abrupt.

  • Gain Stage Carefully

    Proper gain staging is critical. Set your input so the compressor receives a healthy signal—around 0 VU or -18 dBFS in digital terms—then match your output level to avoid loudness bias during A/B checks. In plugins, use input/output trim instead of DAW faders for accuracy. Waves users: disable the noise option unless you specifically want the vintage hiss.

  • Preserve Transients

    If the sound becomes dull or lifeless, raise the threshold or reduce the ratio. The 160’s fast attack can flatten transients quickly. Adjust until you hear transient detail return while still maintaining control. This is especially important for snare, kick, and percussive tracks.

  • Parallel Compression for Added Density

    Use parallel compression to thicken a track without losing natural punch. Set the DBX 160 to a higher ratio (6:1 or more) with noticeable gain reduction, then blend it with the dry signal. Hardware users can send it to a parallel bus; plugin users can use the built-in mix knob.

  • Shape Low-End Response with Sidechain Filtering

    On the 160X or plugin models, engage the sidechain high-pass filter to prevent low frequencies from triggering compression too aggressively. This keeps kicks and bass controlled without flattening them. UAD’s model features a smooth, musical filter; Waves offers more surgical control.

  • Program-Dependent Timing Control

    The DBX 160 doesn’t offer manual attack or release controls; instead, it reacts dynamically to the input signal. You can still influence its behavior by adjusting the ratio and threshold. Higher ratios and lower thresholds make it react faster; lighter settings slow it down slightly, helping shape response by ear.

  • Creative Overdrive and Input Saturation

    The 160’s input circuit can be driven for a subtle, musically useful saturation. Push the input gain until you hear a hint of grit, then back it off slightly. The UAD and IK Multimedia plugins emulate this safely in digital form, allowing harmonic texture without clipping.

  • Use It on Drum Direct Mics

    Apply the 160 to close drum mics to catch sharp transients. As the signal gets louder, the 160 automatically tightens control. Set the ratio to taste—higher ratios (5:1–6:1) for punch, lower (2:1–3:1) for more openness. Adjust until you hear a touch of distortion, then back off slightly for the sweet spot.

  • Enhance Room Tone on Overheads

    On drum overheads or room mics, push the compression harder than usual to bring out room ambiance. Lower the threshold and increase the ratio until the decay becomes more apparent, then balance the output level to keep it natural in the mix. The 160’s fast response helps reveal space and sustain without reverb.

  • Use for (Not So) Subtle Bus Glue

    Though known for punch, the DBX 160 can do gentle bus compression too. Set the ratio to 2:1, threshold for 1–2 dB of reduction, and use Over Easy mode if available. It adds cohesion to groups without squashing transients—especially effective on percussion or background vocal buses.

  • Serial Compression for Consistency

    Use the 160 first in a serial chain to catch fast peaks, then follow it with a slower compressor (like an optical or variable-mu) for tone shaping. This dual-stage method maintains dynamic consistency while preserving character. Plugin users can stack emulations—UAD’s LA-2A after its DBX 160 is a proven pairing.