15" bell B&H/Besson Eb questions...

[arpthark]

Howdy,

Does anyone know if, on a midcentury 15" bell Boosey & Hawkes Imperial or Besson compensating Eb tuba,

1. the valve stems on the top 3 pistons are a different length than the valve stem on the 4th valve?

2. Did the bore size on these instruments change over time?

3. Are parts (besides the bottlecap styling cues on the Bessons) interchangeable between Besson and Boosey & Hawkes models?

[arpthark]

I'll add one more:

did the 15" bell E-flats and the 17" bell B-flats have the same bore size?

[sweaty]

On the one I bought from you, the valve stems are the same length. I would not be able to answer the other questions.

[arpthark]

Thanks @sweaty. That does help. I actually ended up with a Boosey and Hawkes 3+1, same basic model as your Besson, but about 20 years older and in bright silver instead of satin. However, there are a few weird inconsistencies I am trying to chase down with it.