I have to confess that I've returned my Yamaha to the usual rotation for quintet stuff, paired with the Bb 184.
I played a 621 with a larger bell at the Army conference this year. It was sitting there so I put a mouthpiece in it and tried it out, close on the heels of playing Eastman's latest F-tuba prototype. I thought a lot of it with the larger bell. A guy walked up and asked me what I thought. Turns out, it was his personal instrument he'd left in that spot while fetching a demo instrument to compare to it.
He forgave me.
I wonder if this Chinese version is 1.) any different from those currently sold with a Yamaha label on them or 2.) any less expensive than what I paid for my Yamaha back in the first year they were available. In those days, the 621 was the affordable alternative when a performer needed an F tuba that played well for a new gig. They lost that affordability pretty quickly, it seems, but fortunately after I bought mine.
As to the 621 as a design concept:
1.) The blandness or inflexibility of the tone for me is a feature, not a bug.
2.) The angle of the valves has never been uncomfortable for me for whatever reason, and mine has gotten, well, LOTS of playing time (it's the only tuba I've owned that earned more in gigs than it cost--and in this case by a very healthy margin).
3.) the Monel valves have been sticky as hell played outdoors in the heat and humidity of San Antonio summertime. I had to lap them a touch, and found that Ali-Syn synthetic oil was the only oil that seem to keep the Monel from developing stiction with the brass casing.
4.) the valves are not vented from the factory. Chuck Daellenbach showed me how they were vented on his C version, and I cut vents into mine in the same spots. But I didn't have a lathe or mill and knew better than to use any sort of drill, so I machined slots instead of holes using a Dremel cut-off tool. That worked perfectly, but I'm still kind of surprised I had the courage (or stupidity) to do that myself. I did think about it quite a bit first.
5.) I've never owned an instrument that stored water in so many creative places.
6.) the brass strap eyelets are soft. I lined mine with nylon wire ties to keep clips from further wearing through those eyelets.
7.) as Lee Hipp once described it during a visit, with the 621 there is a ceiling above which it will not go. When one needs more volume, the only strategy is to use a shallow mouthpiece and go trombone-like.
8.) speaking of going trombone-like, a 621 works very well for bass trombone parts in quintet arrangements scored for two trombones.
9.) but otherwise, a 621 seems to work best with a contrabass tuba mouthpiece, and not a specialist F tuba mouthpiece. This has been the case less since I learned how to play the low register of a B&S, however.
Rick "whose 621 has probably seen its value cut in half because of these clones, but it's okay because it's not for sale" Denney
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