How to make Bode Analyzer frequency response go lower than -180 degrees?

[willy7593]

Dear community friends,

I am trying to do an audio analysis of my microphone & speaker.

I've realised a big zig-zag in the frequency response after 4.5 KHz. I've tested this on oscilloscope manually and figured out it should have a frequency response lower than -180 degrees but this plot doesn't do it.

Is there any way I can get a more accurate bode plot for my system?

 Frequency response

I have connected AI0+ with AO0 and AI0- with AO's AGND for the speaker.

For the microphone, I've connected AI1+ and AI1-.

Thank you in advance!

[altenbach · Accepted solution]

The "degrees" is not a frequency response, but a phase, which wraps at the boundaries of -180/180 degrees, of course.

If you don't what that, use unwrap phase on the phase signal before graphing.

Do you have access to the LabVIEW code?

[willy7593]

Thank you for replying.

Yes, I've realised it is the phase I wanted to unwrap, can you let me know how to do it?

I do not have access to the LabVIEW code.

[altenbach]

---

@willy7593 wrote:

I do not have access to the LabVIEW code.

---

Well, then you can't unless the programmer has implemented such a setting. Maybe you can export the data and unwrap it yourself.