I have been wondering about this too, and asked about it some time ago, but I did not get a reply (about the sampling rate of the mod matrix, so I guess it is at the same rate as P12 and PRO2, which seems to be at about 11Khz or 22 because of Nyquist rates)

I am fairly certain though, that the oscillator signals are converted to digital because otherwise it would make one hell of a routing analog circuit when you have 32 different destinations slots... The oscillators are clearly digitized (they are available as sources for control purposes) , and these are then used to modulate the destinations. I bet each analog parameter like cutoff, osc pitch etc. Have one DAC associated with it, and that this one number holds the sum of all modulations done to it from various sources. I think the mod matrix would be very hard to do in the analog domain. Many destinations are both digital and analog in nature, and would not allow for connection without a bunch of convertion cucuits... If all is kept digital, and all control sources are converted to digital before entering the matrix, then all would be compatible in the digital domain all the way thru, untill an end modulation can be Delivered to any destination accessible, and those destinations being analog in nature only need to convert this number to analog before hitting the parameter.

Others have covered most of the territory, but there are likely a few other subtleties.  Being able to control how stereo sounds are collapsed to mono (mix both channels, left only, or right only) leaps to mind.  I can’t remember if SampleRobot give you fine control over tuning on a per-sample basis, but PXToolkit also lets you adjust out-of-tune samples in cent increments.  Getting even more esoteric, you can use the same sample file more than once in an instrument without duplicating the sample data (useful for skewing the odds in a round-robin situation, but doubtless also in other situations I haven’t completely explored.)

These kinds of things are easier to accommodate in a tool built for a specific instrument and its export format rather than software designed to target a range of instruments.

Aw, come on now, fellas.  As strange as it might have seemed, that sample and hold effect represented the rocks tumbling down the ravine.  Okay, so maybe I went too far with it....  

My next piece will be all white noise.

Dare ya! (Seriously, I've wanted to try that, but the best laid plans of white noise mice etc...)

Looking forward to hopefully trying one out tomorrow.

Its made by Dave Rossum... The king of Samplers (E-mu systems) so it is only logical... Also being the father of the SSM chips does not make it any better.

The Ultra samplers are still to this day the best sounding 100% digital samplers, period! All of the custom chips that went into them, and patented interpolation algorithm is part of the mojo.