Sound Pure's Take

When a mix or master is 95% of the way there, standard parametric equalizers can sometimes feel too surgical or introduce obvious phase distortion that strips away cohesion. The Gyraf Audio G23-S was designed specifically for those critical finishing touches, offering one of the most elegant, unobtrusive tone-shaping topologies in high-end pro audio.

At the heart of the G23-S is its revolutionary 1dB/octave linear tilt filter. Unlike traditional tilt EQs that pivot around a single cutoff frequency—often creating localized phase shifts—the G23-S spreads group delay across eight full octaves. Turning the tilt control creates an almost ruler-straight response curve that naturally darkens or brightens an entire track or mix bus without making it sound "equalized". To fine-tune the extremes, Gyraf added a subtle 3-band Baxandall tone control (shelving Lows and Highs, wide-Q Bell Mids) with three selectable frequencies per band.

What makes the "-S" version an absolute powerhouse in modern hybrid studios is its Dual-Technology architecture. With a flip of a switch, you can toggle between a classic tube/transformer circuit—driven by E88CC/6922 tubes and custom Lundahl transformers for rich analog depth—or a ultra-clean, high-speed solid-state driver with active servo-balancing. It essentially gives you two distinct processing personalities in a single 2U chassis.

From Gyraf Audio

The Gyraf Audio G23-S stereo tilt equalizer is an original idea of ours – the first ever equalizer based on fully linear one db/oct filters. The way we implement filtering allows for very gentle overall tonal corrections without losing much subjective phase coherence or mix integrity. All-tube signal path, or modern solid-state technology, accessible with the flip of a switch.

The G23-S is an updated version of Gyraf Audio G23 – now including an option for selection between all-solid-state technology or classic tube circuitry. Gyraf Audio added an additional step to the bypass switch - marked "S" - which instantly shifts you into solid-state land: Inputs become differential instrumentation type in stead of transformer, active equalizer stage gets controlled by a state-of-the-art opamp, and output stage gets servo-balanced in stead of tube/transformer drive.

What sets it apart from all other EQ designs is that Gyraf Audio designed it around a highly linear 1dB/oct slope filter, so that rotating the control will adjust an almost ruler-straight response curve, to a maximum steepness of 1dB/Oct. So what you acheive in the 1dB/Oct function is to "spread out" or distribute the "needed" phase roll across the whole spectrum, meaning that at any given interval, only minute amounts of group delay is apparent. In total, it allows quite some correction without sounding "Eq'ed". And because you'd occasionally want to correct outer ends of spectrum, they have added a gentle Baxandall tone control, shelving lows and highs, wide-Q bell mid, each at three selectable frequencies, that they spent quite some time optimizing.

FEATURES:

  • Mainly for mix and mastering
  • Option for selection between all-solid-state technology or classic tube circuitry
  • Designed around a highly linear 1 dB/oct slope filter
  • Gentleness and subtlety are G23-S design targets

Warranty

This item is sold without the Sound Pure 3-year warranty (used / B-stock / dealer-exempt). Coverage terms for items in this category live in Terms & Conditions, Section 27.

Returns

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