Kirchhoff-EQ is the ultimate 32-band parametric equalizer designed for all critical professional applications. It features improved sound quality consistent with analog curves, 15 smoothly shaped filter types, and 32 classic EQ types modeled from real devices. The built-in dynamics processing functions are very flexible and have ultra-low distortion. All of this pushes the Kirchhoff-EQ to the next generation standard. Equalizers will never be the same again.
▬ Robust Nyquist Matched Conversion –
With the originally developed “Robust Nyquist Matched Conversion”, Kirchhoff-EQ has made the frequency response in the digital domain closer to its analog counterparts without the high frequency limitations of conventional IIR (infinite impulse response) equalizers. This method applies to all filter types in Kirchhoff-EQ.
▬ High precision processing –
64-bit version is mandatory and non-negotiable. Kirchhoff-EQ’s internal processing is always done in 64-bit (or 117-bit) format, regardless of the host’s current DAW precision.
Topologies of psychoacoustic adaptive filters
All line filter structures should have the same sound on paper. However, in real applications, rounding errors cause each filter structure to sound different: some are better at low frequencies, some are better at high frequencies.
A technology called “Psychoacoustic Adaptive Filter Topologies” has been deployed at Kirchhoff-EQ. The filter structures move into a “best fit” state with corresponding band frequency changes, resulting in optimized sound quality at both low and high frequencies.
▬ Switchable ultra high 117-bit processing –
Since there are already 64-bit versions, why not go further? Kirchhoff-EQ uses a technique called “Double-Double” to achieve 117-bit internal processing accuracy! This is the first equalizer in the world to achieve such accuracy. You can switch between 64-bit and 117-bit at any time. It will satisfy the most demanding ears.
* Linear phase always uses 64 bits because it is a FIR (finite impulse response) filter and does not support 117 bits.
▬ Filter types –
15 unique filter types
low-pass, high-pass, bandpass: stepless adjustment from 0 dB/octave to 96 dB/octave;
call, notch: stepless adjustment from 12 dB / octave to 96 dB / octave;
low shelf, high shelf, sloping shelf: infinitely adjustable from 6 dB/octave to 96 dB/octave;
flat slope and flat top;
sword: has a sharper slope than a bell, specifically designed to “dig out” resonances.
bottom brick wall pass, upper brick wall pass, low allpass and high allpass.
▬ Infinitely Variable Slopes Filters –
The slope of most types of filters can be continuously adjusted from 0 dB/octave, 6 dB/octave or 12 dB/octave to 96 dB/octave. Would you like to try the 8.125 dB/oct high pass filter?
32 filter types modeled after historical vintage EQs!
Get vintage and modern at the same time! We modeled 9 vintage hardware EQ blocks, totaling 32 EQ types implemented in Kirchhoff-EQ. Benefit from robust Nyquist conversion: each EQ type matches the source equipment exactly and will not compress near the Nyquist frequency. As a next step, unlike the original hardware which only allows you to choose between a few frequency positions, we have modified the DSP model to make adjustable frequency points for all of these types! Each type in these models can be used with regular EQ types or other modeled types, and can also be used with dynamic functions (except bass and treble types). This gives you more freedom and convenience to work.
*Nonlinear behavior not simulated. All types of vintage filters contain only the ideal linear parts of their physical model.
▬ Zero-Latency/Analog/Linear/Mixed-Phase Modes –
Kirchhoff-EQ’s phase mode can be switched between zero-latency mode, analog mode, linear phase mode, and mixed phase mode to meet all your phase relationship needs.
* Regardless of which phase mode is currently in use, if dynamic features are enabled for a filter band, it will operate in minimum phase mode (will not affect other bands).
▬ Mixed phase mode –
Zero latency and linear phase modes sound very different. Kirchhoff-EQ provides a mixed mode that uses zero delay when the bandwidth point is low and uses linear phase when it is high. Each band can smoothly switch between minimum and linear phase according to their frequency.
* There is no noticeable crossover between filter types, while in mixed phase mode the transition is smooth.
▬ Flexible dynamic EQ functions –
The dynamic features in the Kirchhoff-EQ are not just a bonus, they provide the richest features you’ve ever seen. Allows you to achieve the unlimited possibilities of dynamic EQ functions. All types of filters (except low-pass/high-pass, bandpass and notch), even these vintage ones, can be used with dynamic functions.
▬ Harmonic Shift Envelope –
All dynamic EQs have odd and non-integer harmonics, these are the laws of physics. Using advanced DSP techniques, Kirchhoff-EQ now “shifts” most of the energy from odd harmonics into even harmonics, creating ultra-low noise and enhancing the sound. Now you can freely use the dynamic features without worrying about ruining your sounds.
▬Reversible Threshold –
You can now simultaneously control how the speakers respond to the portion of the signal above/below the threshold. In the Kirchhoff-EQ, the High stage works as a compressor or upstream expander, and the Down stage works as an expander or upstream compressor. For example, you can boost the signal below the threshold AND compress the signal above the threshold to “stabilize” the band.
▬ Relative envelope detection/detection –
Let’s imagine a simple case: we’re playing an audio clip where sounds around 1kHz are 9dB. You might be thinking, “The 1kHz band is overloaded, we should cut it down to 1kHz.” But we must also consider the overall level. If the whole sound is 30dB you won’t feel like 1kHz is too much, instead you might feel like it’s not enough. The best criterion for determining whether a band’s loudness is high or low is its relative contribution to the overall loudness envelope, not just its absolute dB value.
So in Kirchhoff-EQ we introduce “Relative Envelope Detection/Detection”. Dynamics is affected by both the current bandwidth and the relative portion of the “relative” bandwidth. The contribution of Relative Envelope Detection to dynamics is also configurable: when set to 0%, it degrades like a normal dynamic EQ; and with a value of 100%, the amount of dynamics is fully calculated from the relative share.
The “detect” band is set according to the frequency and Q factor of the default band, “Relative” is the entire sound envelope by default. But they can be installed freely.
Detection bandwidth and relative bandwidth have freely adjustable frequency point and Q value. Or turn on “SC” mode to use “Detection” or “Relative” with side chain signal.
▬Onset Detection Mix –
When the Onsets mix is enabled, the envelope detector reacts more specifically to transients within the envelope. This way you can fine-tune the tone of the transients. For better customization, you can “mix” the envelope detector and the start detector. For example, you can compress the high frequencies a bit, while compressing the sharp rise in the high frequencies more aggressively.
Equalizer will never be the same again:
Kirchhoff-EQ is a superior 32-band parametric equalizer designed for mission-critical professional applications. It features exquisite sound quality, analog modeled curves, ultra-low distortion dynamics processing, 15 filter types (smoothly shaped), and 32 vintage EQ types that emulate real devices.
High Precision Machining :
By default, Kirchhoff-EQ works in 64-bit mode, but in order for the internal processing to reach 117-bit precision, a technique called “Double-Double” is used! This is the first equalizer in the world to achieve such accuracy. A technology called “Psychoacoustic Adaptive Filter Topologies” allows filter structures to intelligently change themselves to a “best fit” state, resulting in optimized sound quality without compromising low or high frequencies.
Full palette of analog and digital filter types :
Kirchhoff-EQ includes 15 unique filter types ranging from conventional low-pass, high-pass, bell and shelving to more esoteric flat slope, flat top and sword filters. Take advantage of 9 finely matched vintage EQ models and fully variable EQ points not found in the analog domain.
Selectable Phase Modes :
To meet all your phase relationship needs, the Kirchhoff-EQ phase mode switches between zero delay mode, analog mode, linear phase mode, and the original mixed phase mode, which uses zero delay when the band frequency point is low, and uses linear phase when it is high.
Deep and powerful dynamic EQ capabilities:
The Kirchhoff-EQ’s dynamics processing isn’t just a bonus, it’s some of the richest dynamics you’ll ever see. With two-way thresholds, adjustable “onset” control, and a relative definition option, you can do what other equalizers simply can’t: Compress and expand simultaneously to help “stabilize” a given frequency. transient equalizer separate from the body. Or effectively connect one frequency band to dynamic activity in another. Even vintage modeled curves can be applied to dynamics processing.
Endless possibilities and intuitive controls :
The Kirchhoff-EQ has every feature imaginable in an EQ, including spectrum capture, oversampling, lookahead, mid processing and monitoring, stereo width, EQ global scaling and more, all optimized for ultra-low CPU usage.