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Understanding clocking. - continued – Tiptop Z-DSP User Manual

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Understanding Clocking. - Continued

As we’ve discussed, the Z-DSP has a built in DSP

processor. Along with the processor is a pair of 24bit

analog to digital convertors (“ADC”) on the inputs and

a pair of 24bit digital to analog convertors (“DAC”) on

the outputs. The ADC samples the analog audio signal

into digital data, while the DAC takes the digital data

and converts it back to analog form. The programs

that run in the Z-DSP work on this digital data, just

like you would run a program on your computer to

crunch data for your taxes.

The clock on the Z-DSP is what controls the speed of

the DSP. In normal conditions, this clock runs at 32khz

(the “sampling rate”) which is fast enough to allow the

ADC/DAC pair to provide 15Khz of bandwidth. The DSP

uses this clock as well, but multiplies it to create

processing speeds fast enough to run programs and

keep up with the flow of data from the ADC.

This is a standard DSP clocking mechanism with a

clock at a fixed frequency, and as long as nothing is

plugged into the Z-DSP CLOCK input, this is what the

Z-DSP will provide. That’s all about to change…

By using the CLOCK input of the Z-DSP, we can

change the sampling rate of the ADC and the

associated speed that the DSP is processing data.

That allows us to slow down the ADC, or if we use a

VCO to provide the clock, we can vary the processing

speed across time… There is a lot of sonic exploration

to be done here!