chkhld/jsfx

EQ 560 gain/Q interaction problem?

jonlinnarson opened this issue · 1 comments

I love your EQ 560 (it's probably the greatest graphic EQ there is in JS format) but I noticed that there might be a miscalculation in the max Q value.

In line 79 the maximum Q value of 5.763566 seems too large. If you divide it by 8, so that it becomes 0.72044575, the gain/Q interaction becomes pretty much identical to UAD's API 560. I don't own a real one (unfortunately) so I can't say for sure that this is how a real 560 behaves, but UAD are usually pretty close with the filter shapes in their EQs.

I did upload my own modded version to the Reaper stash, but I should ofc have asked you first. If you'd like I can remove it again!

Thanks for your great work!

(PS: Now that Reaper has native plug-in instance and FX-chain oversampling it could make sense to have a on/off control for the internal oversampling, just in case someone wants to use the FX-chain oversampling function)

chkhld commented

Don't worry, you don't need to remove your file from the Reaper stash. 😆

This EQ is not supposed to be a direct copy of the 560, but granted, I did A/B it with a few hardware and software clones. I set the values to what I think sounded good, not to what an actual 560 sounds like.

Already at the time of uploading, I considered if it's worth renaming it to something else so it won't suffer from this "but it doesn't sound exactly like" problem. But I couldn't think of a better name, so project name 560 it was. 🤷

At some point in the future, I'll re-visit several of these plugins and update them, I'll consider the oversampling switch if I can remember. ;)