ReaFIR
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ReaFIR is an expansive plug-in that includes a precision EQ, a fast attack/release precision compressor, a noise reduction system and Left/Right convolution!
Contents |
Some Considerations
- Keep the analysis floor at -90dB or more. The floor represents the lowest value it can display and should thus be set to around the noise floor of your set up (-96dB for 16-bit and -144dB for 24-bit).
- While setting the analysis floor high (for example, to -20db) is VERY handy for making small/precise adjustments, it isn't well suited as a default view for the analysis window because you won't be able to see the entire depth of the audio signal.
- If an audio signal is peaking at a total of -6dB (on the master buss), the highest individual band may still only peak at -20dB, since the analysis window shows the peaks for each individual band. The master buss in Reaper shows the sum of all bands.
- Generally, setting the FFT window size higher than the Default 4096 will result in much more CPU usage and slower updates of the analysis window. Setting the FFT window very low will produce more artifacts. the bottom line: use this setting with caution.
- Clicking the "reduce artifacts" check box on will do just what it says and "reduce the amount of audible artifacts" that ReaFIR sometimes produces. However, it will also limit ReaFIR's effectiveness in each mode.
ReaFIR Rundown
There are 5 modes you can use ReaFIR in.
- EQ
- Gate
- Compressor
- Convolve L/R
- Subtract
EQ
In EQ mode, you have the option of using precise lines or points (located in the "edit mode" drop down list). Using precise lines is well suited for making extremely narrow cuts, or you can start with precise mode, and then switch to points mode which will keep the general form of the EQ curves, but convert it to points.
EQ Mode Tips
- Add in as many points as you want simply by clicking on the red line that appears in the analysis window.
- Delete points by holding CTRL and left clicking a point with your mouse.
- Right Click a point and Choose "set" to manually set a point
- Make a small, narrow cut or boost by setting the analysis floor to -10, then place two points at 0dB along the spectrum that will serve as the maximum and minimum affected area of the cut or boost (this serves the same purpose as adjusting Q in other EQ plugins). Place a third point in between the max/min points and raise or lower that third point to make the cut or boost. For example, to affect a range of 100Hz with a cut in the centre of that range, set 1 point to 300hz at 0dB and another at 400hz at 0dB with a third point at 350hz. Lower or raise the point you made at 350hz to taste.
- hold down shift while changing the gain of a point to make sure you don't accidentally move it across the spectrum.
- Create a ridiculously sharp 80hz High Pass filter by setting one point to 81hz at 0dB, and another point to 79.9hz at -90dB! You can make the filter smoother simply by dragging the point set to 79.9hz lower down the spectrum (for example, to 40hz)
- You can change the gain of entire EQ curve up or down by holding CTRL + moving the curve up/down with your mouse.
Gate
In gate mode, the red line acts as a threshold. Think of the threshold in a gate as working opposite to a compressor's threshold. For example, if you set the threshold High in gate mode, less sound will be allowed to pass through the gate, but setting it lower will allow more sound to pass through.
Gate mode can be used for a variety of things, including traditional gating of a track, but also for midi triggering (i.e you can gate out specific bands, or frequencies by using the EQ curve in either precise or point mode!)
Compressor
In Compressor mode, ReaFIR acts as a fast attack/release multi band compressor. However, there are some notable differences between a regular multi band compressors and ReaFIR. With ReaFIR, you can choose specifically which frequencies you want to compress (without worrying about crossover), and you can even upward compress a band!
You can set the ratio from a very gentle 1.01 to an extremely hard 100:1 using the ratio slider that appears.
In compression mode, ReaFIR's Red line acts as the threshold (in either preside or point mode). Because of the flexibility of this threshold, you are able to choose exactly what gets compression. (for example, gradually lowering the threshold between 1-2khz, or defining a threshold only below 100hz to compress bass frequencies). This can result in some very transparent compression, and the FFT window will show you how much gain reduction is happening in grey - the original signal's frequencies will still show as red.
- Use the EQ tips above to see the different ways you can manipulate the threshold in compressor mode.
Convolve LR
In Convolve L/R mode, ReaFIR does an operation called inverse FFT (IFFT). Without going into too much detail, the process is that ReaFIR compares the Left and Right channels of a stereo signal and multiplies them together. ReaFIR then further processes this with IFFT. The result is that frequencies that are the same on the Left and Right channels re-enforce each other (so you will hear them), while dissimilar frequencies do not - (so they weaken or vanish completely).
So what you will hear in Convolve LR mode is the "like" frequencies from the Left and right channels together and any dissimilar frequencies will be faint or non-existent. This is useful to check the overall balance of a mix to see what is happening sonically - especially if there is too much of a frequency band (in other words, an extreme build-up of like frequencies).
You can also make EQ adjustments in convolve mode using either precise lines or points - which can help you make decisions about what needs to be done within a mix to balance it out.
