I can't paste in the whole article because it includes sound bites to play:

In Search of Lost Sounds
Why you've never really heard the "Moonlight" Sonata.
By Jan Swafford
Posted Tuesday, March 2, 2010, at 7:06 AM ET


http://www.slate.com/id/2245891/pagenum/all/

I like the definition of the melody with the softer, 'ghostly', middle. 'Gong' is a very correct of a description for the lower bass notes.

"The sound is startlingly different from a modern piano and takes a while to get used to. These instruments were mostly played in small to medium-size rooms. The sound is intimate; you hear wood and felt and leather. The voicing is varied through the registers rather than the homogenous sound of modern pianos. On the Katholnig, the effect of holding the pedal down in the "Moonlight" has a ghostly effect, most obvious in the longer-sustaining bass notes that can sound like a distant gong. All these elements of the pianos Beethoven knew shaped the music in the first place, including the way he picked out high and low notes around the murmuring figure in the middle of the keyboard".

I've actually heard it quite a few times. Even by their definition, thankfully, because it sounds great!

Thanks for the link, I liked the soundclips of music played on period instruments a lot.

Excellent link thanks.