Non-nord technical sampling/theory question.

[jazzystu]

I'm pretty sure this can't be done, I'm wondering if you lot know otherwise.

Traditional sampling has a bunch of sounds per note which are selected by how hard you whack a particular key. So, that covers anything with keys. The notes are quantised into fixed pitches and a pitch bender distorts the sound by moving all the components of the sound a fixed difference which buggers the tone up. As soon as you bend the pitch, a lot of complex sounds distort and sound "synthesised".

I'm interested in how you could reproduce something with a continual pitch variation, like a slide guitar or a trombone?

Obviously, it would be possible to mic up the source and make a nice up-note and a nice down-note, but how could you go about controlling this?

With an old modular synth, you could use a "ribbon controller" where you were able to give the oscillators a continually changing voltage which would give you a continually changing pitch. I need to do this, but with a sampler.

Are there any programmes which can do this?

Thanks, Stu

[Hanon_CTS]

......... As soon as you bend the pitch, a lot of complex sounds distort and sound "synthesised".....

Hi Stu,
IMHO you're referring to a phenomenon called aliasing.
Aliasing occurs during the playback of a sample, whereas the original sampling rate wasn't high enough to accurately capture all of the frequencies/ harmonics of the original sound.
The formulae for best sample rate is based on Nyquist-Shannon sampling theorem.
Aliasing is very prevalent in the following situations:

low sampling rate, below 44.1 KHz.
Tuning any sample too far away from it's original frequency.
Not using a low pass filter to remove unwanted high frequency artifact.

With regard to pitch bend and quantization of controls in the digital realm;
All microprocessor based equipment must convert analog style controls and signals into digital "numeric" form to be understood and used by the digital electronics.
The most common example would be the traditional pitch bender. This pitch bender is basically the same type of potentiometer used in both the analog synth of old, and digital synth/ rompler of new.
In the Minimoog it created a continuously variable voltage which could directly control the oscillator pitch.
In digital based instruments, that same potentiometer has to pass into an analog to digital converter to become a numeric based signal.
This is a staircase versus a slope, the number of stair steps is defined by the resolution of the A/D converter.

In more relevant terms: a pitch bend via MIDI has 8,191 distinct steps from center to max. When bending a third, or a fifth, it is very difficult to hear this as anything other than a smooth slope. When programmed to bend several octaves the staircase becomes very apparent.

The analog synths like the Minimoog and ARP 2600 have no such limitation.
With most audiophiles, Vinyl versus CD, analog tape versus sampling arguments will rage on for decades.

I believe the short answer to your question is no.