Comparing my Sterling Virtuoso from 2008 with the Yamaha Neo from 2016: both are rather unproblematic intonationwise. Except one note: I canīt cope with the extremely flat concert C/1st valve on the Yamaha Euphonium. 13-fingering is better but not good. Iīm used to lip down the typical candidates on compensated euphoniums. So i hardly use the trigger on the Sterling and donīt miss it on the Yamaha. The problem for me is to lip up notes especially the higher ones. Lipped up High C on the Neo is similar difficult to hit as high B is difficult to hit on most other brands.
If a piece requires high C I donīt need a trigger on the Neo. I simply grab the Sterling for that piece and play the C without trigger in tune.
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Sterling Virtuoso / Giddings Kadja
Yamaha 642 II / Giddings Kadja
Yamaha YBH 831S / Giddings Kadja S
Yamaha Flügelhorn 631GS / DW2FL