I'm not sure if this is a great plug that I just can't comprehend properly, or a plug that's a bit useless. It seems to do a lot of hugely complicated and very pointless things, but maybe I'm just not using it correctly. It's free and one of the REAPER stock plugs. It has 5 modes: 1. EQ (pretty obvious how to use and what to use for) 2. Multiband compressor. It's a compressor combined with a frequency analyst so that you can apply compression just to specific frequencies, like a super flexible multiband compressor with infinite bands. It has no attack or release, just a threshold curve and a ratio. I think that this could be useful, but I'm unsure how to use it properly. How do you know which frequency bands to compress the most? I guess that you can make certain frequency bands louder by using it with EQ for make up gain of specific bands. 3. Multiband gate. Exactly the same and the compressor, but a gate. I think that this is totally useless unless you want to make weird noises- and there are plenty of better ways to make weird noises Actually, having said that, when I play with it it helps me to understand the make up of a sound: where the resonances are etc 4. Convolve L/R. I have no idea what this does, or why you'd want to use it. I don't think anyone does. This description is on the wiki: 'In Convolve L/R mode, ReaFIR filters the left channel's signal with the right channel's signal, and applies the adjustment curve as an EQ control.' Eh? 5. Subtract This does good de-noising. You can feed it a sample of noise and then it will remove those frequencies from any sound. I understand it completely, and it's fine. Can anyone help me with 2, 3, or 4? Especially 2, cause I have a feeling that that's the most useful one.