The pipework was divided among the various divisions of the organ's musical scale as follows:
That account is in the past tense, as I later made a minor (but significant) change. On looking at the organ, there was something quite unusual about it. Behind the violins there was a wall of trumpets. Where were the saxophones and clarinets, usually evident on Gaviolis of this size? This was more noticeable once the violins had been removed.
This organ had started life as an 87-key (built in the small Black Forest town of Waldkirch, so presumably it was keyless from the start) with no registers. It had been modified some time in the past to play on the more useful scale of 89-G4 by adding violins on register and register control to the clarinet mixture and counter-melody trumpets. Dismantling the organ revealed why these trumpets were so prominent- more of that later.
The first task in dismantling the organ was stripping off the façade and side cases. Then the pipes were removed and stored. At the back of the organ was a set of cello pipes playing on bass. These were not original to the organ, being of orchestrion design with very narrow scale. They were positioned in the open space above the action relay, making tuning access to the other pipework somewhat awkward, and access to the action relays impossible. I made a mental note not to put these pipes back - their speech was not great, and so quiet that they could never be heard anyway.
The trombones had to be removed in a particular order, according to their accessibility, and this order was noted for reference during their re-installation. Once all the pipes were out of the way, their mounting blocks were removed. This was when I found the reasoning for the unusual layout: the counter-melody pipes consisted of saxophones, trumpets and flue helpers, normally arranged with trumpets and flue helpers at the back (with common wind holes), with the saxophones in front. In order to put the trumpets on register they would need to be separated from the helpers. This had been done by transposing the trumpets and saxophones, so that the saxophone reeds and flue helpers were in a line (with some pipes planed thinner for fitting). As the trumpets are the largest pipes in the set, these were the only ones visible. They were now free for register control by a membrane action in the mounting block. I needed to think of a way to achieve this with the trumpet and saxophone pipes put back into their original positions.
The violin pipes ( three ranks) had been mounted in front of the trumpets in place of the original clarinets (unfortunately discarded). Also, there were only 17 violin notes instead of the usual 22 on the G4 scale. In devising this scale Gavioli had been very clever in allowing 22 melody notes when there were only 17 on the 87-key scale. He borrowed 5 notes from the piccolo for use when the violin register came on, shutting off the corresponding piccolo pipes. This was usually done with a membrane on the piccolo action, but not on this organ as the violin register worked in reverse, being membrane instead of ventil. Membrane action is "charged" when the register is off, and ventil action is "charged" with the register on.
The three ranks of "clarinet mixture" pipes, mounted on the riser at the back of the organ, needed to be operated on register on the G4 scale. This had been done by blocking off the wind holes within the riser and fitting a separate relay. While removing that and the main action relay, and all the associated tubing, I realised that there must be a simpler way to achieve the same result.
When it came to checking the tubing runs to and from the keyless action relay, I found that there was no connection to the register cancel. This meant that all registers had been permantly "on" - the organ playing "forte" all the time. I also noticed that some of the neoprene tubing had decomposed to the extent that it had left a brown sticky mess everywhere - a good reason to never use that in an organ. There is no register box on this organ, the registers being "latched" on with a clever use of latching pallets mounted on the keyless relay.
When the case was cleared it became evident that it had been screwed together instead of the usual dowel and glue cabinet jointing. When this organ was built in c1907 Gavioli's main factory was in Paris, but there was a subsidiary works in Waldkirch where this organ was built. This indicates that maybe some parts, including the case, were made in pieces in Paris and shipped to Waldkirch for assembly, and vice-versa.
All that remained now were the 8 bass pipes mounted beneath the floor. At this point I enlisted the help of some of the Emmett crew to tip the case onto its back. All eight pipes were removed together, as a unit; their individual mounting screws could only accessed once they were clear of the case.
The empty case picture shows, at the far end, the rectangular opening for keyframe tubing with the original music slot above it with a corresponding slot at the opposing end, at far left in the picture. Just to the left of the keyframe opening can be seen the angled screw hole for assembling the case.
Having emptied the case, the task of overhaul and re-fitting began. I decided to restore the organ to a period in it's life when it was first converted to 89-keyless. Keith Emmett rejected the idea of taking it back to 87-key. However, I corrected Alfred Lenk's methods somewhat, with a more consolidated approach. Financial restrictions prevented me adding the missing five violin notes, however.