I serviced a Grotrian 275 built in that same time which was in the recital hall at a University I worked at for 17 years. For many years in the 80s and 90s. It had a fundamental weakness of power in the fourth and fifth octave below the duplex, and it was quite apparently due to defective design of the forward, waste length from the Agraffes to the Tuning pins. There was considerable loss of energy through the aircraft because of an inadequate deflection of the spring, apparently deliberately designed into the piano.
I proposed a simple solution which would have deflected the string a little bit of the agraffe, but this was rejected by the school.
I never forget when a prominent pianist performed a recital and that great Rachmaninov Etude-Tableaux turned out to be impossible for the Pianist to play due to the huge crashing base octaves in the left hand, which he could not bring down enough for the powerful octaves in the middle, which are of course the motif. We had a fine 7 foot four Feurich with a good balanced scale that he could've performed it on, but he was already used to the Grotrian and by the time I came along to tune for his recital. He was immensely disappointed in that, and for good reason.
I discussed the instrument, and its problems with Klaus Fenner at a conference, and he had a low opinion of the design. I seem to remember him disliking the long front waist lengths in general as well.
My predecessor at that university also expressed the opinion that this was a high tension scale with a substantially loaded soundboard, and it depended on the right balance, which was easily compromised through the cycles of weather. I'm not a certain about this, but I would strongly recommend making sure you're bored has sufficient crown and down bearing.
I note with some amusement That before I left at school, it received a donation of a second Grotrian 275, which, in addition to the same problem, had severe string rendering issues.
I think the difference between the 220 and the 275 is significant. I've never seen a 220 I didn't like.
I suspect that the 275 could be modified with a small amount of trouble to be a fairly decent instrument, even if not a large hall piano. But not Every 9 foot should be a large hall piano anyway
Regards,
Bill
Bill Shull, RPT, M.Mus.
www.shullpiano.com
www.periodpiano.org
909 796-4226
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