EXS 24 Logic Sampler Users Group

DIGITALMechanics@... wrote: 

>
> But how can it guess what note is going to play next? I seriously doubt 
> there is any kind of look ahead function in Logic, EXS or Kontakt, and 
> AFAIU without such a function the overall difference would be minimal. 
> Am I missing something here?


As I'm sure you understand, the audio data for your samples is stored on the
media on linear tracks. The caching is controlled not by the application
(EXS24) but by the drive firmware --that is software stored on ROM on the drive
-- it is the program that runs on the drive's internal microprocessor--
including the cache controller. The caching controller's strategy might be to
read the whole track into cache rather than just the bit that is currently
being requested. If you need the data in subsequent sectors on that track a
short time later they might still be in the cache. 

In my long piano notes example (holding down a chord with the sutain pedal so
that you have to read a bunch of 30+  sec long piano samples off your sample
drive) without caching,  the read head would chase around the media reading a
succession of small segments of those long notes. The result might mean that
the heads return many times to the same file to read its data to produce one
continuous tone. If caching is employed some or even all of the subsequent
returns to that note might be avoided -- the whole note might have been read
into cache on the first partial access. In that case all subsequent requests
for that note's data will be relayed to the EXS24 direct from the cache.
Perhaps 8MB is too small to really make a big difference here -- 128 MB might
really accelerate this sort of application dramatically.

Unless you work for a drive manufacturer and are privy to their testing and
cache controller programming methods this is all guesswork  and the only thing
you can do is test the finished products youself of find a relevant published
review.

Regards,
Murray