That does not surprise me. I can imagine that mouthpiece volume can also accentuate or mask leaks in a horn depending on the synergy of the two.

Same goes for the facing curve and response characteristics of an particular piece.

 

Yep, and the opposite is always true. Which is why anyone should be wary of a repairer who play tests horns on a close set up with a soft reed…….

 

Absolutely.
And I think the repairer who worked on this one is someone who plays on a more closed tip with a softer reed.
(Legatos)?

 

It may be true that a leaky horn plays a bit easier on a smaller tip mpc. I haven't ever tested that, so based on the OP's experience, I'll assume it could be true, at least in some cases. But the horn either is either leak-free or it's not. I know I've played through leaks on my tenor in the past on an open tip mpc (.120) without realizing how bad the leaks were until after my tech fixed them. The difference was very noticeable. Bottom line, it's much, much better to play a horn without leaks, regardless of what mpc you are using!

 

This is most definitely true.
One man’s “leak free horn” is another man’s sieve.
The difference between A horn with minor leaks and one that is completely leaks free is immediately noticeable.
Probably more so with a more open piece though.
At least for me the leaks were far more apparent when on an open piece.

 

When I play the keys without the blowing through the sax and they pop with very little finger pressure, there are no or very slight leaks.
Bruce Belo is a very skilled tech and sets up all woodwinds/brass well.

 

This is an interesting topic. Having played and repaired saxes for quite a few years, I have found that leaks in the instrument cause a "resistance" when I play and also make notes less responsive---especially in the low register. Playing on a stiffer reed also feels more resistant and makes the low register less responsive. The same strength reed will feel stiffer on a mouthpiece on a wider tip than one with a smaller tip opening. I play test instruments I have worked on using mouthpieces I have used for years and am comfortable with. I feel a "familiar" set-up" gives me the most accurate feedback to evaluate how well all of the pads are sealing.