As you can read below, the instrument reviewed below is not really a fully-qualified Sonata.
I have saved this information mainly because of the intonation results.
I will update this page someday when I get to test a real Sonata.
One of a kind, blended Leblanc Sonata
One of my major hobbies is fixing clarinets. I recently purchased two brand new keyless replacement joints on eBay. These were probably supplied to a USA dealer in order to fix cracked or broken Sonata clarinets. The joints came to me brand new, with the springs installed, but not bent into position. I eventually found that a more recent model Normandy 4 clarinet had similar keys. And I bought one that had a badly cracked right hand joint. So the clarinet I am reviewing has a Leblanc Normandy 4 keys, bell and barrel, while the body of the clarinet was made by Leblanc with the Sonata logo.
The left hand joint is stamped with the serial number D45921, while the right hand joint is simply stamped 13! I can't see any reason why either joint would have been considered rejects. It is likely that there were some tolerances that are off. However, the clarinet plays very well in tune, as would be expected of a Sonata clarinet, which is considered entry level professional-grade.
Intonation, low F to throat tone F, playing an F scale loudly. I was using a 64.6 barrel, not the Normandy barrel.
(When I use my standard B45 mouthpiece and #4 Legere Quebec cut reed, I am always too flat using a standard 66mm barrel. I always play "stupidly loud" when testing intonation, not trying to lip notes up or down.)
Mid F to F at the top of the treble clef, playing loud. Notes shown in between an F scale, like the F# below, are just blips. I didn't play an F#.
Higher register F to high F, playing loudly.
Results show that I need to put a bit more cork under the side B-flat key, which I will do. But the E and F at the top of the treble clef are surprisingly high.
In general, this is excellent intonation, but perhaps not living up to other Leblanc Sonatas.