How does bass quality and bass extension work?

[Revolite]

Polk S15, 50Hz frequency, many complaints of poor bass
IK Multimedia iLoud MTM, 50Hz frequency, universal praise

Are there any numbers I can read to understand the differences here? I understand they are different products but is bass not bass?

 

[NTK]

Their respective measurements and reviews are here:
https://www.audiosciencereview.com/...imedia-iloud-mtm-review-active-monitor.18347/
https://www.audiosciencereview.com/...olk-audio-signature-s15-speaker-review.15437/

The iLoud MTM has built-in DSP and auto-EQ. It uses EQ to provide a pretty flat FR almost to 50 Hz. However, it can only manage to do that up to a certain (and not very high) output level, beyond which it is going to fall apart (but its limiter will kick-in as there isn't much point to go further other than destroying itself). So, they will do quite well if you don't need them to play loud (e.g. desktop use only).

The Polks are passives, have poorer measurements, will likely require some external EQ help, but, according to Amir, can give impressively high output. Bass didn't seem to be a problem for Amir (who is a serious basshead).

You can compare the distortion measurements (particularly those at 96 dB SPL) to get a feel for the differences in their output capabilities.