Testing audiophile claims and myths

[sander99]

I knew there were some more or less recent, expensive consumer/hi-fi speakers with actively monitored (laser or optics) and corrected feedback implementation for the woofers (don't even remotely remember the manufacturer or even what they looked like)

Not very recent but expensive yes, the German brand T+A had loudspeakers with optical feedback:
For example T+A Solitaire OEC 2000.

I actually saw and heard these around 1985 or so.

 

[gregorio]

Are there any driver designs that build in mechanical tolerance compensation, similar to how feedback works in amps?

I’m not sure that’s really relevant. Driver designs of course also have tolerances but they’re very different to the tolerances of analogue components, which in turn are very different to the tolerances of digital components. Driver designs have to account for the laws of physics pertaining to motion; mass, materials rigidity, inertia, etc. (which limits accuracy, dynamic range, etc). Amps have to account for none of that, the limits are only set by thermal noise, the motion of sub-atomic particles and electromagnetic fields, so far higher tolerances are not only possible but cheap. Digital devices are limited by nothing at all, except processing power (bit depth and sampling rate), for example a dynamic range of thousands of dB is trivial.

G