QA-401 Output signal

Hi Matt,

I am using the QA-401 in conjunction with Bob Cordell’s Distortion Magnifier.
Things are going well but I do have a question for you.

When I press on the run/stop button to take a measurement the output sine wave from Gen 1 or 2 pulses. It is not a continuous steady output sine wave.

This makes tuning the Distortion Magnifier much harder.

Is it possible to change a setting somewhere that would allow a continuous output from Gen 1?

Kind Regards


If you press the IDLE GEN button, the GEN1 will output a steady state signal. Not sure about GEN2’s signal as I have not used that one. The unit will not measure anything at that point, however, it is just a source, so I am not sure if you will be able to use the Distortion Magnifier…

Thanks for the response scott.

The idle gen button?
Is that in the latest version as I don’t see it.

I am using the latest software for the QA402, which I believe works with the QA401. Here is my screenshot showing the IDLE/GEN button:

Thanks Scott, I’ll try and download the latest version and give it a go.

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Hi Scott, this is off topic but I’m getting a Calibration error when connecting the QA-401

I used the -QA401 switch and I’m definitely connected because I can change the attenuator but I can get any output from the QA-401 by using the run or Idle gen buttons.

It says calibration data loaded but it invalid.
See log file for details. However I can’t find the log file

Any ideas?

I am afraid I don’t have an answer for that :cold_sweat:

That’s fine, no worries scott.
Maybe Matt will read this post over the coming days and respond

P.S. the QA-401 worked fine with the Distortion magnifier

Thanks for your help

Well, you gave me more things to look that I was not familiar with- Linear Audio magazine and “distortion analyzer”. Luckily for me, for the older gear that I look at the QA402 is just fine just as it is :grin:

Hi @Stuartmp74, currently, the QA401 doesn’t work with the new software. It will come, the the various silicon shortages have required just about every product to get re-designed and it’s taking an enormous amount of time.

On the QA401 software, you can generate a continuous tone via Settings->Generate Fixed Tone

Thanks @Matt I’ll give it a go. :grin: