05. 112A (1956) Wurlitzer Electronic Piano
For the next duration, I will be uploading documentation on every model of Wurlitzer Electric Piano ever produced, chronologically. Approximately 1 page per model, 5 instruments per week, around 40 instruments total. And then the accessories.
This will take a several weeks, as each page is a photo essay… and an essay. In the meantime, if the instrument you are curious about isn’t here, I refer you to my complete list, on which these blog entries are based: Here.
The Wurlitzer Electronic Piano Model 112A. Pratt-Read Action. A radical internal physical revision from the Model 112, which deserved more than the mere “A” appended to its model number. Deceptively bland external appearances aside, this amounts to a prototype for the Model 120, the very different Wurlitzer Electronic Piano that would dominate for the next 5 or 6 years.
Note: If you believe you have a 112A, you may actually have a 112–I encounter this mistake often from callers. Many later 112’s have an amp inside labeled “112A.” You need to check the serial plate on the back of the instrument. If yours is missing, check for the location of the sustain pedal attachment holes.
Pedal mounts not on right side, but on bottom, behind middle E and F, for the first time (a pedal design which is retained, with only modest changes, through 1983). These and 120 series are arguably even more complex/ difficult to regulate than earlier actions. (See more detail on this in the Model 120 entry). The action has springs only in the damper arms. (The earlier action designs had a return “butt spring” above the hammers.)
Compared to both the 112 and especially the 120, these are rare. All known instruments are in a range of a little less than 500 serial numbers. Since some of those numbers were used by 120 amps, the number produced could be as small as 250. My guess is that it’s somewhere in-between those two numbers. 250 to 500.
In short, this is a briefly available hybrid of the 112 (reeds, basic look of the exterior, later “112A” amp also found on 112) and the upcoming 120 (same middle-mounting pedal, and very similar, though not identical, action). Lead sustain brick still covers top 8 notes, instead of the 11 notes of the upcoming 120, so this action has three more dampers than the 120.
They didn’t bother making a manual for it, even though its significant changes warranted one; they just inserted a couple of new pages into the 112 manual.
Other than the pedal mount, I’m not sure you’d be able to distinguish one from the other without opening the lid. I don’t see the 112-style bakelite side handles on any examples of these, but they may have all broken off (as is the case in most 112’s).
Conventional wisdom has this model following 112, after the 112 stopped. But the serial numbers are interspersed with known 112 numbers, in both the 6000 and 7000 ranges. Evidence now strongly suggests that the 112 and 112A were produced in parallel throughout most of 1956. I hypothesize that they began producing these while also using up 112 backstock, and began putting the newer “112-A” amps in the remaining 112’s. Why the “P” designation at the end of some serial numbers? For “Pratt Read” action? Quite possibly.
According to Fred DiLeone, the key sticks are longer than on a 120, with a stop at the back to prevent them from bouncing up. They are also different from the 112 keys. Through trading photos, we compared reed bars with a 112. They matched one of the 112 reed bar variants (from early in 1956, as opposed to the mid-year version…. strangely).
Here, we have two different reedbars from examples of the prior model, the 112. (I’m discussing this here, because the 112 page is already overloaded with data, and it applies to both models.) The top one is masking-tape-dated to March 23 1956, and the lower one is dated to June 12, 1956. They have subtle differences in design, many of which seem related to ease in removal from the action (=not breaking hammers when taking out or putting back in). There may be earlier variants in the 110, 111, and early 112‘s. This is a worthy subject for further research. It is the earlier March version that was also found in a recent 112A.
In this photo, the 2 reed bars are oriented as each of them were when under the damper arms of their 2 respective instruments (that is, with bottom end towards the front). These are the tone-producing elements of the piano. The hammers swing up and hit these reeds, which vibrate, producing a change in capacitance which is conveyed from the pickups to the amp.
You can see the most basic conceptual limitation, from a future tuning-maintenance perspective: The reed screws are at the BACK, which makes them difficult to access when under the damper arms. In the earlier models, you can sometimes lift a damper and tune a note here or there, if awkwardly (and perhaps ill-advisedly in many cases). Starting with the 112A, the redesigned damper will not lift enough to allow access to the reed screw. There are two ways to handle this if retuning: remove several or even ALL the dampers (after numbering them– that’s crucial); or remove the harp and retune it outside the instrument (which is probably the way it was done back then). The most important aspect of the redesign of 1962, from a tuning-maintenance perspective, was to rotate the reeds in the reed harp 180 degrees, so that the reed screws faced out. This makes it possible to change a single reed without removing the works. This saves hours of labor.
This bar also shows clearly how reed length works in every single Wurlitzer EP ever produced. The first 20 notes decrease in length linearly by 1/20th of an inch, from 2 19/20″ to 2 inches. Then, the remaining 44 notes decrease linearly in length by 1/44th of an inch, from 2 43/44″ to 1 inch. There are 3 reed blanks, and they correspond somewhat to the three sections of reed bar. The leftmost section and pickup contains the 20 wide-tongued bass reeds. The central section contains medium-width reeds 21 through 42. The top section continues with the midrange style blanks for #43 through 50, followed by a clearly delineated shift in pickup depth for the top, narrower 14 notes (which are the only reed design which will be retained into 1963).
Below, for comparison, is a reedbar from the next model, the 120. The sustain block is longer, and the most of the reeds are shaped differently (wider) and require hammers to hit them at a different “strike point,” which may mean that this reed bar locates them differently in relation to those hammers. I describe this in a little more detail in the next post. Nonetheless, most of these reeds will not fit in the pickups of the reed bars pictured above. It is common to find pickups widened in “style 1” reedbars to accommodate later style reeds (in fact, you can see that this has been done in the upper of those two reedbars, which is why the lower one was bought). This makes the reedbar unfit for restoration. Don’t do that.
As I’ve never heard at 112A played, I wonder: Is the strike-line of the hammers here different than on the 120, to take into account the different reeds? (If you put a lower register 120 reed in a 112, it doesn’t do so well: Hammers “thud” in an nodal spot, and presumably vice versa. But, theoretically, you could put a 120 reedbar in a 112A IF the reeds were located differently.) Or, did they change the specs on the 120 reed bar and reeds because this setup wasn’t working so well?
If your interest is primarily in this specific model of Wurlitzer, I nonetheless encourage you to read my posts on the models 110, 111, and especially 112 and 120. There is a lot of ground to cover, and I go into more detail about design features shared by ALL of these instruments on those pages.