[LAU] Sampling an external oscillator waveform

F. Silvain silvain at freeshell.de
Tue Feb 10 13:00:35 UTC 2015

Hey hey,
I want to sample the waveform of an oscillator of a hardware synth. One period 
of the waveform must have 65536 points in the end. Will the following process 
Samplerate 48kHz, Oscillator pitch 71.0449218750000Hz, becasue:
71.0449218750000Hz / 48000Hz = 97/65536
In theory I can now create an empty table with 65536 entries and fill every 
97th entry (with wraparound) with successive samples from the original audio 

I see a problem: the soundcards ADC must average/interpolate the digital 
samples from the analogue input arriving in between samples. I can't tune my 
synth to 48000/65536Hz.

I can increase my samplerate to 96kHz and work through the sample process as 
above, but will that help? Am I completely on the wrong track for creation of 
an adequate copy of an analogue waveform?

If a correct process is more complicated and requires more mathematics, I will 
drop the idea as such.

* Internet: https://freeshell.de/~silvain
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