Identify Faulty Speaker

[BatHat]

Hey!

I work in event technology and sometimes we get defective speakers in the workshop. Instead of listening for the fault, I would like to use REW more often.
One speaker distorts slightly. In the mdat file, I have named the speakers A and B. Could you possibly tell me which one might be defective based on the data and then explain why?

Both are the same type of speaker. Coaxial design. Measuring microphone directly in front of the speaker. Measured in an acoustically unfavorable booth.

Best regards, Bathat

 

[sm52]

The measurements are almost the same. There are no obvious signs of defects of one of them. They both have a problem with HF. You must listen. If you don't like something in their sound, to understand. Measurements can show something, but may not show any problems.

 

[BatHat]

I thought I could identify some problems with Distortion / THD etc. I tried it on other speakers.. Small ones with heavy distortion - but the THD was more "flat". Maybe it was because of the distorted signal that creates harmonics

 

[dcibel]

It's possible that the SPL just isn't high enough to reproduce the problem. It's also possible that the problem requires more than a single tone like a sine sweep. For identifying things like rub/buzz, I've found it's often much more easily identified with a multi-tone signal. So you can also compare multitone IMD result. Use RTA and generator, select "show distortion" on the RTA. If you save the RTA result, then go to the distortion tab, you can observe the IMD result without the fundamental signal present for easy comparison.

Comparing your measurements as-is, I probably wouldn't identify either as "defective".

 

[Wayne A. Pflughaupt]

I’m certainly not up on all the wonderful functions the newest versions of REW offers, but it seems to me a simple listening test can get results faster than you can set up REW to operate.

A spoken word recording played through a speaker at low volume will reveal a damaged woofer voice coil immediately, as you’ll heard a faint buzzing "following" the audio.

The same might be true of a high frequency driver as well, although they often fail catastrophically and simply quit working.

Regards,
Wayne