Frankieve, we were informed quite a while ago that, while the drum loops streamed, the guitar loops have to be loaded into RAM (but perhaps not the same RAM as is used for the sampler) because the HD couldn't stream that many simultaneous streams.
You see, while the drum track only needs the ONE stream at a time, for all the guitar chord choices you have the ability to make on the fly, the latency of coming off the HD would preclude that. I believe AJ told us quite a while back that the guitar loops are ROM (no matter where they are stored) and the drum loops are RAM.
I mean, if the guitar loops were streaming, there would be no problem having as many chord types as the chord recognition engine could know. But three simultaneous chord types was the maximum that Ketron could achieve. And that had to be from RAM. When you think about it, having all those chord choices INSTANTANEOUSLY available requires hardware speeds. In fact, from some of the reports we have got about glitchy timing occasionally between style divisions, especially Intros, it seems the poor thing is having a hard enough time just streaming ONE stereo file in realtime when asked to change streams... Imagine how much harder that would be having multiple Parts, all but the drums with multiple chord choices.
Computer systems SEEM to have a much easier time of this, streaming multiple files simultaneously, but the thing is, they aren't REALLY realtime. The computer will pre buffer data (because it knows what is coming) to give the illusion of realtime performance. It only needs a few milliseconds to do it, but in a realtime environment, those few milliseconds are just enough to give you glitches and stinky timing.
Personally, as expensive and as unproven as this technology is, I think I am prepared to wait a few more years until the hardware catches up to needs, and the whole thing gets a bit more mature. It just seems a little kludgey right now.