| Digest Nr | Subject and Author |
 |
| 2020.10.30.01 |
Early T-100 Welte-Mignon Dual Sustain Pedal Speeds, from Jim Miller |
| 2020.10.23.03 |
Early T-100 Welte-Mignon Dual Sustain Pedal Speeds, from Jim Miller |
| 2011.04.25.02 |
Dual Role Piano Plays Duo-Art & Welte Rolls, from Dave Geissinger |
| 2000.03.14.07 |
Dual Reproducers for Edison Phonograph, from John Kadlec |
| 2000.03.14.05 |
Dual Reproducers for Phonographs, from Mike Knudsen |
| 2000.03.13.13 |
Dual Reproducer for Edison Phonograph, from Jim Canavan |
| 2000.03.13.12 |
Dual Reproducer for Edison Cylinder Phonograph, from Jim Moore |
| 2000.03.12.06 |
Dual Reproducer for Edison Phonograph, from Martin Anderson |
| 1999.06.09.02 |
Identify Dual Spoolbox Unit, from Dick Beery |
| 1998.05.06.13 |
Steinway Welte With Dual Spoolbox, from Dave Saul |
| 1998.04.01.19 |
Craig Brougher's Dual Pouch Regulator, from Peter Coggins |
| 1998.03.25.11 |
Kilgen "Dual Control" Pipe Organ Player, from Marc Kaufman |
| 1997.11.05.15 |
Dual Roll Player for Organ, from D. L. Bullock |
| 1997.11.03.08 |
Dual Roll Player for Organ, from Dick Beery |
| 1995.12.28.02 |
Dual Disk Porter Music Boxes, from Jack Hardman |
| 1995.12.28.01 |
Dual Disk Porter Music Boxes, from Bob Ebert |
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