Sun Nov 20, 2022 2:01 pm
I don’t have much experience with this organ beside listening to some of the demos, but I think it is a good one, one of SP’s best. The stops have more baroque character than most neo-baroque organs, and the mixtures aren’t harsh, as you say. The reverb sounds like it is just right between not too wet and not too dry.
The best explanation of why it’s called the sesquialtera that I’ve heard is that it comes from the Latin “sesqui,” which means half, and “altera,” which means alternates, and that this describes how the 1 3/5 rank looks like it’s half the size of the 2 2/3 rank on the board. Before the Baroque period, they were usually full ranks, but by the Baroque period it was customary to include breaks, and I think I prefer them with breaks. They are a bit more interesting that way.
The cornet usually has 8’, 4’, 2 2/3’, 2’ and 1 3/5 ranks with no breaks, and traditionally doesn’t include the bottom two octaves. However, starting in the romantic period you get experimentation with the basic formula, including breaks and the addition of septieme’s.
The Septieme rank 1 1/7 is usually used to add quiet reedy character to another stop or another reed, starting in the romantic period.
The None 8/9 was used by the Italians to add interest/reedy character to a full plenum, but some German romantics and modern builders used it for this and to add power to loud reed combinations without making them too loud.
The pedal Sesquialtera is also characteristic of pedal mixture experiments done by German Romantics and moderns around the time of this Sauer. It strikes me as pretty conservative though. The most interesting one in my eyes is the Theorbe, for which a typical composition would be 6-2/5, 4-4/7, 3 5/9. I’ve never heard a real one, but I’ve experimented with the ranks in a CODM organ, and the result can be pretty wild! There are some Baroque Theorbes, but they are all unison sounding pedal reeds.
You can get some pretty cool sounds out of them, however the problem with a lot of these funky aliquote stops is that they don’t blend very well with other stops at different pitches. So they are usually used to add reedy character to other stops or to bolster an already loud reed combination or plenum combination without adding a lot of volume, but otherwise don’t have a lot of use. Because of that, they aren’t often used. I still think they are cool though!