The R and D that the Pleyel company did in the 1890’s is as valid today as it was then. They found out very early on that these harps had to be built like battle ships. They are heavy and rigid, with a huge metal ‘keel’ under the soundboard to support it. For this reason they have a completely different resonance than a pedal harp. You really can’t hear it on this recording. In person, they sound ‘tubby’, with a lot of resonance but not a really clear attack. Debussy hated them, but wrote several pieces for chromatic harp for the money.
I’ve had a Pleyel chromatic harp in my living room for 20 years or so and have been wondering what to do with it.