Classic British EQ.


BQ-A 4-Band Equalizer

The BQ-A based on Classic British EQ from the ’70s. With a surprisingly wide range of tonal variations, the BQ-A is an invaluable and professional audio tool with great flexibility and excellent sonic ability.

The main of the EQ section allows four frequencies at any one time, switchable to one of four frequencies: Low Filter (Shelf): 50, 80, 100, 150 Hz; Low-Mid Filter (Bell): 250, 500, 1k, 2k Hz; High-Mid Filter (Bell): 3k, 5k, 7k, 9k Hz; High Filter (Shelf): 8k, 10k, 12k, 15k Hz.

A series of three high pass filters at 18 dB per octave and three low pass filters at 12 dB per octave are arranged at the ends of the EQ section. They are unique in that the switches can be pushed in simultaneously, offering distinct cut filter combinations with unusual filter curves.

The BQ-A extends the features of the original hardware and joins the flexibility of the digital world to the character of the analog processing. The BQ-A plugin designed from the ground up for fast, efficient work on mid/side, stereo and the objects, the beds (fixed channels) of immersive mixing environments.

Surround profiles do not work correctly in Logic Pro, this is due to a bug in Logic Pro compatibility with AUv3 on multi-channel tracks (When Apple fixes this, our plugin will work correctly). AUv3 on multi-channel tracks works absolutely right in Reaper.

Latest Versions

AUv3 version 3.0.0 (Jul 14, 2023)
VST2 version 3.0.0 (Jul 14, 2023)
VST3 version 3.0.0 (Jul 14, 2023)

VST2 version 3.0.0 (Jul 14, 2023)
VST3 version 3.0.0 (Jul 14, 2023)


USD 79
USD 29



Fx Selection

This module allows you to select a equalizer from four available. The equalizers are arranged in series, this allows you to process channels with different equalizers settings. For example: the first EQ is only the mid channel, the second EQ is only the side channel, the third Eq is the left and right channel. For multi-channel modes: the first Eq is only the left and right channels, the second EQ is the center channel, the third EQ is the LFE, etc.
You can rename Fx Buttons for ease of use. To rename the selected Fx button, right-click on the button.
In order to turn on the solo (listen) of the equalizer, double-click on the selected equalizer number. The equalizer in solo mode glows yellow, to exit solo mode, double-click again. For two-channel modes, only one equalizer can be solo mode. For multi-channel modes, one or more equalizers can be soloed.
To bypass Eq processing, press the selected equalizer number one click + shift. In bypass mode, the button will glow red.
You can also copy all equalizer settings to another equalizer. To do this, select the equalizer from which you want to copy the settings, then click on the copy button, then select the equalizer to which you want to copy the settings.

Input Routing
Input Routing lets you choose between 44 common channel setups, starting from Stereo up to 7.1.4 and 9.1.6. Simply select in the input routing module the channel setup that fits your track.
You can also create your own input routing profiles. 16 independent channels are available.
Click on the edit button next to the input routing selection display. Hold down the shift button and select the desired number of channels. Name selected channels in order. Then click save and name the profile.

Channels Selection
In this module, you can select (activate) the channels that the equalizer will process.



The layout of the BQ-A equalizer is simple and easy. You have four different bands of equalization, with a frequency selector and a gain knobs each. Low and High Pass filters can be activated by pressing the off-white buttons.

The four equalizer bands have two controls each – a “frequency selector” knob and a gain knob. The fader will boost the signal up to 15 dB by dragging the fader to the right and attenuate the signal by 15 dB by dragging it to the left.

Low Shelving Band
The frequency options for the Low Shelving Band are 150 Hz, 100 Hz, 80 Hz and 50 Hz.

Low Mid Band
Bell type with the following center frequencies: 2 kHz, 1 kHz, 500 Hz and 250 Hz.

High Mid Band
Bell type with the following center frequencies: 9 kHz, 7 kHz, 5 kHz and 3 kHz.

The bell filters interacts with each other in a rather funny way. For example, even if the gain of the Low Mid Band is set to zero, changing the frequency of that band will affect the frequency response of the High Mid Band filter significantly.

High Shelving Band
The frequency options for the High Shelving Band are 15 kHz, 12 kHz, 10 kHz and 8 kHz.

When boosted, the High Shelving Band gives a beautiful highend shimmer to just about any material. Don’t be afraid to try it on a master bus, as the result can be fantastic!

Low Pass and High Pass Filters
The Low Pass and High Pass filters are controlled by three buttons respectively, which sets the cut-off frequency for the filters – 15 KHz, 12 kHz and 9 kHz for the Low Pass and 100 Hz, 50 Hz and 25 Hz for the High Pass. The cut-off characteristic is unusual and not exactly coherent but the slope is about 12 dB per octave.

The three settings work independently and can be used in any combination which means that the more buttons you engage, the more attenuation you get. For example, pressing all three Low Pass buttons will actually result in a filter with an even lower cut-off frequency than 9 kHz.




The console was actually designed to have very little distortion, but it was nevertheless possible to crank up the input volume and equalization bands to make it distort, an effect that has been of much use in lots of recordings. The actual amount of saturation depended heavily on the audio material and amplification before the console, so we added the Harmonics knob to make things easier for you.
This knob controls the level of harmonics added to the signal. The distortion is mild and adds some coloration.

Phase (Polarity)
Shifts the phase by 180 degrees.

The EQ is active when the EQ IN button is engaged and its associated LED is illuminated. When this button is off, selected EQ is disabled. Please note that this button disables only the selected equalizer, the rest of the equalizers in the FX blocks are not disabled.

Output Gain
This knob is an output gain control. The available output gain range is ±24 dB.


Comp609 4


Undo and Redo functions allow undo and redo of changes made to the plug-in parameters.

A/B buttons allows you to load two independent settings and compare them quickly.

Preset Display
Factory presets are included in the plug-in installation, installed in the following locations:
Mac: Users\[user name]\Music\Red Rock Sound\RRS BQ-A\Patches
Windows: C:\Users\[user name]\Documents\Red Rock Sound\RRS BQ-A
You can save the current Comp settings as the Default preset. - Full Reset – is the default preset
Load button allows loading of presets not stored in the locations described above.
Save button allows for save of user presets.

Global Output Gain
Global Output Gain controls the overall output level of the plug-in output, after all equalizers.

OS x_ activates 2x, 4x or 8x oversampling, 1x disables oversampling. (note that when the HQ mode is on, CPU will be loaded more than usual).

HQ mode (HQ)
HQ mode is for oversampling, it adds a higher order antialiasing filter. It improves processing quality, but also leads to an increase of the CPU load.

? button opens info page.

D3D / OGL / CPU (Windows)
This switch allows you to choose between GUI rendering engine:
Normally, no need in switching rendering mode manually, plug-in try to initialize D3D9 then OGL (if D3D9 failed) and CPU (if OGL failed) automatically. But if you have problems with the GUI, you can manually switch and test different rendering methods at work.

This switch is available only in the Windows version of the plugin. For the Mac version, this is not necessary.

Note: Drivers of some video cards (for example, Intel Arc A380) in D3D mode adversely affect the plug-in (periodic noise or whistle), if you encounter a similar phenomenon, use OGL or CPU.

SIMD optimization
This switch enables or disables SIMD optimization, it can be used by multichannel processing with high oversampling. It is undesirable to use in mono and stereo modes, SIMD only slows down the plug-in due to the overhead of splitting the data for optimization.
(Currently in beta testing)

- In the ARM version, you can enable or disable NEON; - In the Intel version, you can enable or disable SSE2.

SIMD Windows
- In the Intel version, you can enable or disable AVX (if supported), or SSE2.

The Windows version has a limitation: if the CPU does not support FMA, then the optimization will not work, even if AVX or SSE2 is supported.

Note: Enabling/disabling SIMD is saved in the project for each plugin individually. i.e. if a specific instance of the plugin slows down, then you can enable SIMD for it, and others, if they are in the project, will not be affected by this optimization.