Hi Chris Leslie, the materials on hammers are based on different layers, first layers are leather and top layers are different densities of rabbit fur applyed with no tension with organic glue as well as found in many models of Pleyels from the period between 1830 and 1840 . If interested for more information you can visite www.pianinopleyel.blogspot.com
or ask me via private message the contact of the restorer Mr Olivier Fadini.
Thank you for your interest! . Nice recording isaac!!
maybe a little strong hammers! Did you restored it??
Hello Lluis, no it was one of the pianinos from Olivier Fadini, Palyed by Aya . You surprise me with non tense felts , as a colleague reproduce a model of hammer covering machine from that era and ity use a heavy mass to tense the felt strip.
Both are tense in my opinion, but indeed if you talk of underfelt it is mosty very dense. not the case with rabbit felt.
The pianino recorded have been refelted or lost his leaver coverage, or Pleyel used yet felt at that moment.
I could not regulate the piano much I had only a couple of hours to work on it.