ResEQDemo is a universal binary AU plugin that gives you up to eight parallel resonant filters. It uses convolution modeling of an idealised analog-style peak impulse for extremely rich textures, and can do ‘parked wah’ effects of great sophistication.
The thing is, ResEQ builds a really complicated sort of ‘parked wah’ across a lot of frequencies, and doing that creates resonant (hence the name) tones that contain only those frequencies actively useful to you. It’s like going bonkers with a normal EQ or three and ripping everything that’s not useful. The result will sound very different from what you sent into the plug. You can use it on whatever, though it was designed around heavy guitar, particularly doubled or tripled heavy guitar where you might want additional thickness without screwing up other mix elements.
Note that effectively ResEQ gets rid of anything that will mask other instruments or get in the way in the mix—by centering on a whole bunch of different frequencies and discarding everything else, you can totally whack distortion-fizz no matter what the original tone sounds like. I’d suggest saving good settings as Logic presets, because it might take some time dialing them in, but with eight frequencies available you can have ‘secret guitar voicings’ as tricky to work out as a secret sauce. Try to find spaces in the frequency range to fill out the sound—some midrange, some up in the treble or supertreble, some down lower. The result will resemble a fullrange sound, but it will not mask other mix elements hardly at all.
ResEQ declares one sample of latency.
ResEQ is $50.