The Sonoris Linear Phase Equalizer (SLPQ) is a parametric linear phase equalizer in VST and SAWStudio format. The plugin is suitable for mixing and especially mastering and features 7 bands, including lowpass, highpass, peaking and shelving filters.
The SLPQ can be used to enhance or correct difficult material like vocal or instrumental soloists and groups, orchestral recordings and complex mixes, without introducing any unwanted coloring. The linear phase implementation of the SLPQ ensures a transparent character and just boosts or cuts a frequency range without adding a "sound". It doesn’t smear transients or create mud, nor does it alter the imaging and depth information of the original sound. This way it is possible to boost or cut more than with a conventional equalizer without any of these negative side effects.
The linear phase algorithm of the SLPQ is based on a technique called “backward-forward filtering”, until now only implemented in some expensive high end equalizers. The main advantage of this technique is that IIR filters can be used instead of FIR filters, the latter is commonly found in linear phase implementations. IIR filters are known for their more analog kind of filtering and are also more efficient than FIR filters. The filters used in the SLPQ are actually the same as in the Sonoris Equalizer and also have correct gain up to Nyquist.
Every band can be set up to process stereo, L , R or (M)id and (S)ide channels. Processing the mid or side information can be very useful in certain situations. In mastering for example, it allows you to enhance a centered vocal while leaving the other instruments untouched. Or to center a bass without losing the stereo imaging of the rest. Adjustment of is made easy because the SLPQ allows for monitoring the LR or MS channels.
The plugin has a large graphical display that shows exactly what you get.
The SLPQ has a HQ switch that enables an upsampling mode. In this mode, the SLPQ has an even more accurate response, especially at the higher frequencies.
- 7 band parametric linear phase equalizer
- backwards/forwards type algorithm
- 4 quality settings
- Lowpass and highpass filters up to 48 dB/octave
- Peaking and shelving filters
- Stereo, L, R or MS processing and monitoring
- No pre-warping effects, that is, correct response up to Nyquist
- HQ mode with upsampling for an even more accurate response
- Soft Engage technology on all filters to prevent pops and crackles when switching
- Mousewheel support
- A/B comparison
- Large graphical display with dragable handles for maximum control
- Three zoom levels
- High resolution level meter
- Track following
- Full automation possible
- SSE and SSE2 optimizations
- Settings can be saved
- 64 bit integer math in audiochain, except for the filter code
- TPDF dither is used to convert the 64 bit signal back to the host resolution
In the VST version the internal 64 bits signal is dithered to 32 bits. Some hosts, like Reaper and Cubase accept the newer VST 2.4 double floats standard and in those hosts the output is in 64 bits, undithered.
"This is going to be my "go to" Eq. The sound quality is absolutely stellar! I just did an acoustic folk album using mostly this Eq and it is as like a veil being lifted from off the speakers, the definition and clarity is definitely on par with any other High-End digital Eq on the market."
Mastertone Mastering Studios
"I want to tell you I love the Eq and Linear Phase Eq plugins. They are the best sounding digital eq's I have heard."