The elysia Xfilter Rack stereo equalizer is a versatile tone-shaping powerhouse, equally at home enhancing individual tracks, buses, and full mixes. This true stereo EQ is designed for intuitive operation, letting you dial in musical results fast. Its powerful filter design even allows resonance at the cutoff point — perfect for punchy drums, tight bass, and vocals that cut through a dense mix. With the addition of the signature Passive Massage circuit, you can smooth harsh sources while adding sweet, airy sparkle to the top end. Every serious rack deserves a world-class analog EQ, and the Xfilter Rack delivers.
Getting instruments, vocals, and effects to sit perfectly in a mix is effortless with the Xfilter Rack. Two sweet-sounding parametric mid bands handle detailed tone shaping, while the real magic lies in the resonant high and low bands. These can be switched between shelving EQ and cutoff-filter modes. In cutoff mode, you can add resonance at the cutoff frequency, allowing you to remove unwanted rumble while emphasizing the fundamental punch of bass and kick drums. You can also tame overly bright sources while preserving clarity and presence. These resonant filters make sculpting sounds both precise and musical, helping tracks stand out while blending naturally into the mix.
The unique Passive Massage circuit on the high-frequency band is a secret weapon for polished mixes. It applies a gentle high-frequency rolloff around 17kHz, combined with a subtle resonance boost near 12kHz. The result is a smoother, more refined top end with added presence and air — all without harshness or excessive brightness. It’s perfect for adding sheen to vocals and bringing shimmering detail to acoustic instruments.
The Xfilter Rack is built for true stereo processing that preserves your stereo image without artifacts. Elysia uses computer-selected dual and quad layer potentiometers along with tight-tolerance components to ensure accurate stereo tracking. Best of all, both channels are controlled with a single set of knobs, making it fast and intuitive to dial in professional results whether you're working on a single track or an entire mix.
The elysia xfilter is a high-end stereo equalizer designed for pristine transparency, musical flexibility, and true stereo precision. Built with mastering-grade components and intelligent analog engineering, xfilter delivers open, natural sound while giving you powerful tone-shaping tools. From subtle polish to bold sculpting, it offers exceptional control without compromising the integrity of your audio.
True stereo EQ processing is rare in the analog world due to component tolerances that can cause left and right channels to behave differently. The xfilter overcomes this challenge with computer-selected dual and quad layer potentiometers and specially chosen low-tolerance capacitors. The result is perfectly matched stereo tracking, making it ideal for stereo buses and mastering applications where accuracy is critical.
The outer bands of xfilter are highly flexible. In standard mode, they operate as smooth high and low shelving filters for shaping air and low-end weight. With a switch, they transform into 12 dB/octave high-pass and low-pass filters with a resonant peak at the cutoff frequency. This allows you to tighten low frequencies with added punch or highlight presence in the highs without boosting the entire spectrum.
The two parametric mid bands feature switchable filter characteristics: Wide (Q 0.5) for broad, musical shaping, and Narrow (Q 1.0) for more focused adjustments. These carefully chosen Q values ensure tonal shaping remains natural and musical. Extremely narrow notching is intentionally avoided, as surgical corrections are better suited to digital tools.
A special passive LC high-frequency filter — known as the “Passive Massage” circuit — adds silky top-end polish. It introduces a gentle resonance peak around 12 kHz and rolls off above 17 kHz, enhancing air and presence without harshness. Shielded inductors prevent noise interference, ensuring ultra-clean high-frequency enhancement.
To guarantee precise stereo matching, every potentiometer in xfilter is individually measured and selected using an Audio Precision system. Frequency controls use four-layer pots, and gain controls use dual-layer designs. This meticulous selection process ensures both channels respond identically across all settings.
xfilter’s circuit boards feature a dedicated ground shield layer in addition to audio and power layers. This extra shielding protects sensitive filter stages — especially at low frequencies where resistance is higher — from hum and electromagnetic interference, preserving clarity and low noise performance.
The xfilter|Mastering Edition is optimized specifically for mastering engineers. It maintains the original’s transparency while offering refined controls, extended headroom, and a workflow tailored to critical final-stage processing. Every nuance of your mix remains intact while you make precise tonal adjustments.
All four bands in the Mastering Edition operate within a precise ±5 dB range for highly accurate, repeatable adjustments. Stepped potentiometers, multiple filter types, and detailed scaling make it ideal for professional mastering environments where recall and precision are essential.
With extended +27 dBu headroom, the Mastering Edition provides exceptional dynamic range and prevents unwanted saturation during processing. This allows you to shape even the most dynamic material with total confidence and pristine audio quality.
The xfilter series is available in multiple formats to suit different studio setups, all delivering identical high-end sound quality. Whether you’re mixing, mastering, or tracking, you can rely on xfilter to provide consistent performance and world-class analog tone.
The elysia xfilter is a versatile stereo equalizer built for professionals who demand transparency, musicality, and precision. With fully parametric mids, flexible high and low bands, and innovative passive high-frequency enhancement, it offers powerful tone shaping while preserving natural sound.
The xfilter|Mastering Edition expands on this foundation with enhanced circuitry, greater headroom, and ultra-precise controls designed specifically for mastering. Together, they represent a new standard in analog equalization — delivering stunning clarity, depth, and control for the most demanding audio work.
| Type | Solid State Equalizer |
|---|---|
| Number of Channels | Stereo |
| Bypass | Yes |
| Number of Bands | 4 |
| High Pass Filter | Yes |
| Low Pass Filter | Yes |
| Q Type | Narrow/Wide |
| Boost/Cut Range | ±13dB (Peaking Bands), ±16dB (Shelving/Cutoff Bands) |
| Frequency Range High Band | 700Hz–28kHz |
| Frequency Range Hi-Mid Band | 300Hz–16kHz |
| Frequency Range Lo-Mid Band | 45Hz–2.2kHz |
| Frequency Range Low Band | 20Hz–900Hz |
| Inputs | 2 x XLR, 2 x TRS, 1 x 1/4" |
| Outputs | 2 x XLR, 2 x TRS, 1 x 1/4" |
| Frequency Response | 10Hz–400kHz (-3dB) |
| Rack Spaces | 1U |
| Power Source | Standard IEC AC Cable |
| Height | 1.75" |
| Depth | 8.66" |
| Width | 19" |
| Weight | 4.23 lbs. |
| Manufacturer Part Number | xfilter |
