The Adapter, which fits more or less completely into the original Welte roll compartment, is designed for those who want to play ordinary 88-track rolls. The adapter is very compact and utilises three motors, for playback, rewinding and paper alignment respectively. To save space, the playback motor is placed inside the take-up roll. The paper alignment motor is regulated by opto-electronics, sensing the paper edges. The adapter has a control for tempo setting, and keys that control the pneumatic Welte accentuation system, so that you, as on most 88-track pianos, can change accentuation manually. The Forte pedal can also be activated by pressing a button. The electronics and pneumatics are housed in a special, removable control box. The readout bar has very short internal channels, leading to the holes on the underside, which in turn fits on Welte's readout bar. On the underside is glued a precision-punched leather gasket, needed to get the required, perfect tight sealing. There are connection details available for the adapter, to make it usable on push-up players as well as upright pianos. Thus the adapter is usable in various types of Welte instruments, although I haven't had a chance to measure all the available variants. The prototype I now have fits into my push-up player andin all the upright pianos I have encountered so far. There should be no problem connecting it to any instrument, as only a few connection details are affected. An earlier, simpler and fully mechanical prototype has been tested, and is also working flawlessly, although it has some weaknesses. This simpler variant uses Welte's own take-up roll and rewind mechanics and has no paper alignment (well, neither has Welte's original system). The adapter has a special shaft with a gearwheel, to be inserted in place of the Welte music roll. As the Welte mechanism starts rewinding, an intermediate roil is engaged because of the winding direction, in its turn driving the rewind of the 88-track roll. Because the Welte rolls roll from below and upwards, and the 88-track rolls roll in the other direction, I had to insert the 88-track roll upside down and have it run in an an S-shape path, and finally wind it onto the take-up roll outside in. I regard this as a drawback as many music rolls have their beginnings glued onto heavier stock that "doesn't like" being rolled outside in. Furthermore, some rolls have lyrics printed on, which, in this way will be hidden. Not being entirely satisfied with my first try, I decided to design another, better variant. That's the model described at the top, with built-in electronics and three internal motors. I have decided to manufacture a short series of this one, but should the be interest in the simpler model (which will, of course, be cheaper), I might make a few of them, too.