Welte-Mignon T-98 ("green Welte"), cf. Hagmann, Anhang 11 (p. 179)
and Phillips, p. 121.
98 positions at nine to the inch on paper 286 mm wide, five expression
valves on each side and 88 note positions between them, A0 to c⁵ (MIDI
21 to 108). A roll re-cut from a Mignon master uses only the middle 80
of those, C1 to g⁴, which is the T-100's compass.
The rewind is not a valve of its own: a long perforation on the bass
sforzando-piano position drives it, which is why that position is
named for the valve and the rewind stated separately.
Measured against Julian Dyer's scan of the T-98 copy of roll 225
(Grünfeld, Träumerei): 98 columns 2.818 mm apart on paper 285.6 mm
wide, notes on the middle 80 columns, the sustain valve punched 52
times in the music where the T-100 copy latches its sustain on 52
times. A 53rd perforation on that track belongs to the test pattern
after the rewind.
The paper speed is the Deutsches Museum's figure for its Welte grün /
T 98 rolls, 220 cm/min. Phillips gives 7 ft/min = 2.134 m/min (p. 121);
midi2exp's and PlaySK's green defaults of 72.2 and 72.27, read as the
Stanford convention of feet per minute times ten, are 2.201 m/min, which
is the museum's figure; and the two copies of roll 225 last the same
time if the green starts at about 7.30 ft/min. Welte's own booklets give
no speed, only that the roll must run from the first "A" of the chromatic
scale to the cross-line bearing the dial number in half a minute
(Skala-Rolle 98 §1b). This is documentation; what sets the emulator's
time axis is the spool.
Welte-Mignon T-98 ("green Welte"), cf. Hagmann, Anhang 11 (p. 179) and Phillips, p. 121.
98 positions at nine to the inch on paper 286 mm wide, five expression valves on each side and 88 note positions between them, A0 to c⁵ (MIDI 21 to 108). A roll re-cut from a Mignon master uses only the middle 80 of those, C1 to g⁴, which is the T-100's compass.
The rewind is not a valve of its own: a long perforation on the bass sforzando-piano position drives it, which is why that position is named for the valve and the rewind stated separately.
Measured against Julian Dyer's scan of the T-98 copy of roll 225 (Grünfeld, Träumerei): 98 columns 2.818 mm apart on paper 285.6 mm wide, notes on the middle 80 columns, the sustain valve punched 52 times in the music where the T-100 copy latches its sustain on 52 times. A 53rd perforation on that track belongs to the test pattern after the rewind.
The paper speed is the Deutsches Museum's figure for its Welte grün / T 98 rolls, 220 cm/min. Phillips gives 7 ft/min = 2.134 m/min (p. 121); midi2exp's and PlaySK's green defaults of 72.2 and 72.27, read as the Stanford convention of feet per minute times ten, are 2.201 m/min, which is the museum's figure; and the two copies of roll 225 last the same time if the green starts at about 7.30 ft/min. Welte's own booklets give no speed, only that the roll must run from the first "A" of the chromatic scale to the cross-line bearing the dial number in half a minute (Skala-Rolle 98 §1b). This is documentation; what sets the emulator's time axis is the spool.