The other day I did a simple test : play a very slow sine wave sweep through my sub, and my speakers.

The cone of my sub make a noise at a specific frequencies. It's low, around 30 Hz. Same for my main speakers. But higher, around 50Hz (about).

When I say noise, I mean, the domes resonate so high it creates a noise.

When I touch the dome with my hand, the noise is attenuated (I assume I damped the resonance this way).

Questions are : is it because of a bad speaker/sub design?

My speakers are in good condition, and the 'problem' is are on the two speakers at the same frequencies.

I was thinking using DSP to filter these frequencies. What do you think?

Maybe is there a simpler software approach if I have converter with multiple outputs?

Most loudspeakers distort in the low end because the user wants more bass than he want to pay for.

At what SPL level will your speaker start creating audible distortion? 80 dBC?

Best

No Idea. I didn't use any SPL meter or REW.

Just my phone to check the frequencies.

Is Adam SUB 12 a bad sub? Hmm

If you play loud, speakers will distort. So it's level dependent.

REW (5.19) can show THD (Total Harmonic Distortion) together with Fundamental (the received sweep) and Noise floor.

You can run a couple of sweeps at different monitor level and see what it looks like.

The Sub 12 manual says (around) 1% THD @ 60Hz level: (?) SPL
and max 115dB.


That's opinion.
Is Peugeot a bad car?

Best

Ake

PS I'm not a subwoofer expert.