Just wanted to get things straight on the whole evf in nebula .
First off, is this evf 17?
Secondly ,Were these made only for compressors?
And can old preamps , compressors , tapes etc benefit from this new feature, by changing programs to evf 17? If so , do developers have to deconvole or Create new Program files for old libarys to to make these sound correct.
you can use the new mode everywhere. We preserved compatibility keeping the old RMS 17 and AVR 17 mode. It's a sort of "debugged" RMS 17 mode. I think it's better if you don't change it for compressors released by velinas in Nebula CoreII, because he tuned timings manually using the CoreII engine. Old nebula3 and nebula2 users could take advantage from the new mode.
well, I could explain it in a better way too. RMS mode was calculated squaring input values before the envelope follower, which is plain wrong. In this way you have more or less the same attack values but weird release values. You can't hear it properly in preamp emulations (attack and release are both small values), but in compressors. So velinas debugged compressors modifying values manually and checking the result. It was a nightmare for him.
Someone reported it in the past: bmanic was suggesting AVR mode, and so velinas. Anyway times are still wrong since they are based on tau time and not rise/fall time. So if you compare the same input values with other compressors you get strange attack/release times (but they are simply faster, if I remember well).
Today the EVF mode is derived by AVR, but attack/release times are multiplied by a constant. Nebula stores internally the tau value, and it calculates the correct rise/fall time multiplying it by log 9, which is almost 2. If you need RMS there is a true RMS calculation, based on a moving window (width is selected by attack time, while release time is a dummy value). If you compare EVF 17 mode with other compressors you should get the same timings. We fixed also nat, so it calculates the correct tau time. As I said before, nebula stores it. Than it converts to standard rise/fall times and that's all.