I'm working on a piece that has an 8-bar harp solo (unaccompanied). It's running 32nd-notes, sometimes in 3rds or 6ths or otherwise supported in the bass/treble register. Fundamental tempo is slow, quarter note =50.
The problem is that our virtual harpist is not able to hit all the notes at tempo. (I'm playing back with Sibelius.) Patch is Chromatic Harp 1 Lite. If I slow it down to qtr=40 or less, then it sounds great, all the tones are there crystal clear. If I go up to 44 or 50, there are some dropped notes which are unacceptable for my recording purposes. I'm tracking CPU Usage with the Task Manager and it does not peak above 80 or so during the solo.
What gives? How to fix? I thought a CPU upgrade (Celeron --> P4) would solve it, but no, it didn't.
Because harp notes decay more slowly you could be running into polyphony issues. The faster you play figures (especially in thirds or sixths) the more likely you are to run out of playable notes, thus causing drop outs. Try increasing your polyphony setting for the harp and that should fix it. Highlight the harp slot on your Kontakt player and find the polyphony setting which is under the CPU usage indicator (it will say 0/64). Click on the default 64 and move your mouse up to increase the number of available notes. Just remember though, increasing the polyphony on an instrument will up the CPU load, so raise it in small increments - checking your playback until you get the results you want.
This sounds like a possible soundcard driver issue.
I've been working on pieces with dual harp parts with a P4 2.8 GHz machine with no problems at all. No cut notes or timing problems plus playing the rest of the orchestration. I sometimes overload my CPU in the very dense sections when both harps are playing arpeggios. So it's not your CPU at this point.
I'm using an ESI Waveterminal card which has pretty good drivers.
Loogoo, you won't believe this: you solved the problem, but it only works backwards.
I just tried the polyphony trick. It seemed to get only slightly better, and as I increased the available voices above 80, the problem got much worse and dropped whole phrases. In frustration I screwed the number down to around 40 and all of a sudden the whole section comes alive, every note. This Kontakt sampler seems to be a very strange animal.
Hmm, another mystery (though the problem remains solved):
To test Nickie's theory, which sounds logical, I raised polyphony back up to 64, where it was at the start (default). The piece still sounds fine, as it did with the lower setting -- no dropped notes that I can detect on my cheap headphones. (I am waiting for a set of AKG headphones, on order.)
CPU Usage peaks at around 65. However, even before, the CPU Usage meter never went up even close to 100.