621 receiver size

[PaulTkachenko]

Hi folks,

The mouthpiece receiver on my 621 F is larger than on the Bb I have. Similar difference on my Eb and C too, now I think about it.

Could I get a mouthpiece with a smaller shank? There is only about 1cm difference. It doesn't seem to affect the playing, but I'm curious as to why these lower tubas have narrower receivers (and leadpipes?)

Also, how tricky is it to pop a 5th valve on the 621 Bb, I'm missing low B.

[PaulTkachenko]

Yup, that's what I'm saying ... I have 621 F with a bigger receiver than a 621 Bb.

Here's a pic of the Bb, you can see where the F goes up to.

[PaulTkachenko]

Yes, I'm pretty sure both are original.

The receiver on my YCB661 is the same as the 621 Bb and the YEB631 is the same as the 621 F.

My conclusion is that the lower horns have smaller receivers. I wondered if anyone else had noticed this?

[Tubajug]

I'm afraid I don't have any responses to your questions, but I'm curious, are all three of your 621's identical in size? Outside dimensions I mean? Bell diameter, height, etc? Is the bore the same on all three? I find it very interesting that Yamaha was able to make three tubas in different keys out of the same design.

[PaulTkachenko]

They fit perfectly in the same case.

Just did a gig on the Bb - really good.

[Doug Elliott]

I don't think the difference in receiver size was intentional. It sounds like "normal" variance to me... a sad state of affairs, but unfortunately that's the way it goes.

[PaulTkachenko]

Hi guys,

This is still bugging me. The receiver on my old 621 Bb is smaller than the current models.

Can I get a current Yamaha mouthpiece turned down to fit (see pics earlier in the thread) or do I need a new receiver? Which ia better or is it essentially the same.

[PaulTkachenko]

So, what do we think - turn down a mouthpiece or get a new receiver?

It always seems to be hassle getting Yamaha parts ...