Hi Wim, First, most "modern" harpsichords and fortepianos have transposing keyboards, mostly so than can play at different pitches without retuning. Careful here because string WILL break. Strings do break, in the bass mostly because of too much turning trying to find the pitch. SPlice them if you can or replace them if you cannot. Schaff likely has brass and steel wire for these instruments. The little blocks are likely Backchecks or key stops, maybe both. Because of their low tension and very thin soundboards the pitch can go radical, even ballistic, any day. The tuning will not last further than the hallway when you leave. DOn't sweat it, it is normal and expected. The little beasties are fun aren't they? Newton
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