Post-Processing and EQ

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This model has a large task: to attempt to mimic a wide variety of reed woodwinds. But the only real tone-shaping tool in the model is the shape of the pipe.

So we’ll add a lot more post-processing and EQ to this model than to the previous ones. We’ll put it into the FX section, since it won’t fit in the Voice Area. The G2 automatically gives the FX section its own DSP when necessary, so we have a lot of processing power available to us.

Below is a patch that includes a variety of tone-shaping tools. Useful controls are brought out to the G2 front panel. It’s an FX patch only; the reed model itself isn’t in it.

Step by step

This patch has 7 separate processing stages. They are:

• Remove DC. Like our previous models, this patch generates a DC offset. Although not typically a problem, it can create havoc with waveshapers. Since we’re including a waveshaper later in the patch, we’ll get rid of the DC first. We’ll use a highpass filter for this, and it will double a tone control, too.

• Waveshaping. The G2 Overdrive module is an easy way to spice up our tone by generating additional harmonics. In a single module, we can specify the overdrive type, the amount, and whether the effect is symmetrical or not. It’s a nice one-module solution.

• Trim Harmonics. Just a lowpass filter to trim harmonics. Useful for getting rid of the buzz that the Overdrive module can create.

• Parametric EQ. Some reed instruments have formants that give them their characteristic sound. Parametric filters give us a very precise way to mimic these formants.

• Comb Filters. Another method of generating formants. Just too fun and useful to leave out.

• Volume Control. This is the same circuit used in previous models: an indirect volume control that can be mapped to the keyboard velocity morph group without creating clicks in the sound.

• Reverb & Output. Since we’ve got an entire DSP to play with, why not include the reverb? Also, two separate assignable outputs are included.

Does it matter what sequence the modules are in?

Filters are “linear” circuits, so they can be placed in any order without affecting the sound. This includes the highpass and lowpass filters, the parametric filters, and the comb filters. Even the Reverb module is a fancy kind of filter.

The exception is the Overdrive module. As a waveshaper, it’s non-linear, so its position in the signal chain matters. We want it to be after the highpass filter so that it’s not affected by the model’s DC offset. But we want it to be before the rest of the EQ, so we’re not stuck with that characteristic “overdriven” sound.