Hi,
I have a VI that's supposed to produce an analog output to loudspeakers. It does produce the output, but I've realised that the sound pitch was not what I expected it to be. And I found that the pitch (analog output frequency) varied with the Sampling Rate and the Number of Samples of the Sine Waveform VI. To confirm this observation I checked it with a Function Generator, and found that the frequency was infact different.
So, for the past few days I've been trying to find a solution to this. I would've thought that this is a simple problem, because it's a fundamental thing; finding the frequency of the output signals.
I did find an equation (given below) that describes a way to calculate the output frequency
Output Frequency = [Update Rate × Frequency] / Sampling Frequency
But, I don't know where I could get the Update Rate term in the above equation. Is it defined by the device I use (PCI 6229), or from the program?
I'm quite frustrated by this, as I've spent countless hours just trying to find an answer to this problem, and it's the only thing that's stopping me from carrying out my experiments. I've attached my VI, and I'd be very grateful if anyone could identify what I'm doing wrong, or any obvious things that I'm not doing.
Thank you.
