I was trying to know how many instances of nebula (1.3.412) I could load on my system (Win 7 64, intel Q8400, 4gb Ram) and I noticed some weird behaviour :
With reaper (3.651) I can load about 30 instances of nebula 3 before hearing any crackles on audio but if I use nebula 3 reverb I can't go above 15 (with the same program loaded of course). The cpu meter on the windows task manager is around 40%, the total cpu meter in Reaper shows 40% to but the FX cpu meter shows 100%.
With Cubase 5.5 I can load about 26 with either Nebula or Nebula reverb without any problem (wich is also not really normal as I thought nebula reverb was lighter on the cpu).
I tryed to use nebula free to see if core II would solve the problem but it does the same thing. I also tryed with Reaper x64 : the same
Do somebody have an explanation for this behaviour ?
are you using nebula 32 bits or nebula 64 bits? Reverb version is ligher, but the length parameter for FFT kernels is settled to an higher value, which means higher quality but higher cpu load. Check that you are running in GHOST mode.
Thank you Giancarlo, you solved my problem. I turned the GHOST mode on and everything went back in line (30 Nebula Reverb instances). Thank you Fuseburn for trying to help but changing the anticipative FX buffer from 200ms to 1500ms didn't change anything.