Using a keyboard synth, there’s often enough onboard to tailor frequency ranges (filters, etc.). Depending on which synth pedal you’re using, you might not have as many options for that.
I don’t think using the EQ Compressor is ‘wasting’ a slot, necessarily. If it does what you’re after, then it’s useful in the chain. Especially if you need to target specific frequencies with parametric accuracy, or compress them.
But since you’re relatively new to the H90, I’m going to make a suggestion: Go through all of the algorithms, and note which ones *also* have EQ parameters available.
Many have at least a low & high shelving filter; others add mid frequency & level. You just might find what you need, and have a ‘bonus’ reverb-distortion- delay-pitchshift .. in that slot.
Another suggestion would be to run through the online manual’s Algorithm Guide first. That way, you can narrow down the ones you’d like to try out first.
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