Is this clipping?

Overdriving the amp = clipping. Overdriving the speakers is something else. Either way you stand a chance of damaging drivers.

Many audiophiles believe their tweeters are not in danger with tube amplifiers because they clip so graciously. This not so.

Overdriving the speaker results in damaged woofers.

Agree overdriving amp (clipping) and overdriving speaker are two different (bad) things.

With loud recordings, you have a lose/lose scenario if amp is underpowered. You can keep the volume up as intended and distort due to clipping or be forced to turn it down whether you want to or not.

Regarding overdriving the speakers, you have a different issue but the same choices, distort or turn it down.

if you have both, ie underpowered amp and speakers/drivers that cannot go loud and dynamic effectively, you have th edouble whammy which is more common and more severe with modern loud recordings.

Address both these issues and at least you are in a position to play the game optimally regardless of recording quality.

Clipping is the consequence of over driving.

" If it is clipping on rock then it will clip on jazz too... "

Wrong.

A primer on clipping and other challenges in faithful reproduction of musical peaks was written by Simon Thacher of Spectron and published in EnjoyTheSound:

http://www.enjoythemusic.com/magazine/manufacture/0708/index.html

That's a nice article.

My technical intuition tells me that fast and highly efficient Class D switching amplifiers like the Spectrons or Icepower are tailor made to accurately address the issues associated with dynamics, transients, and clipping better than conventional SS or soft clipping tube amps. What I hear on my BelCanto ref1000m Icepower monoblocks support that. For my application and speakers, in that I want realistic dynamics and transients as much as possible with minimal fatigue causing distortions, none of the power or current available in the ref 1000ms are optional or unneeded I believe. The OHMs in particular are capable of very good dynamics, articulation, detail and and muscle (a tough combo to achieve together) if provided the power needed fast enough and the BC icepower amps have set the bar in regards to that for me.