Gap experts I need your help.

[toakstertuba]

OK, so I'm trying to get this straight. I took a paper clip and got a measurement from where the lead pipe starts to the end of the receiver (1.5"). Then I measured how far my mouthpiece goes into receiver. The difference is 7/16 (.44) of an inch. On my f tuba. From what I've understood this is pretty large. So here's the thing. It's an American ($) shank Blokepiece piece on a Wessex Berg. Same shank on my Luzern (also Wessex) creates an even larger gap (.6+) Anyone experienced smaller than "standard" receivers on their wessex horns? Or maybe they're longer? Mark, have you measured your gap on your Berg?
All of this said, I'm still loving the setup with both my rigs...a lot!... just trying to figure out this gap business and if I've got some sort of smaller than standard receiver on my horns

Travis "'cause you can always make it better?"

[Matt Walters]

If you like the response (articulation) of your current set-up, then the gap on the mouthpiece to tuba receiver is set perfectly for you. I've set even more gap than that for some customers who needed help with a bad leadpipe setup.
Just as people who have "affairs" on their partners, too many tuba or euphonium players with a perfectly good set up keep looking for "something better" when the real problem stares back at them through a mirror.
What is good for one, is not perfect for all. Each horn will take a different gap to match the player with mouthpiece/shank setup of choice and how that person is playing that day, slept that night, ambient temperature and acoustics of the environment, etc., etc., etc.
You can spend forever trying to engineer and build the perfect solution but if you are still in the garage building the car when the green flag comes down, you already lost the race.
Since I never feel the same two days in a row I tweak my equipment for "good" and then make adjustments to the guy that stares back at me from a mirror.

[bisontuba]

OK, so I'm trying to get this straight. I took a paper clip and got a measurement from where the lead pipe starts to the end of the receiver (1.5"). Then I measured how far my mouthpiece goes into receiver. The difference is 7/16 (.44) of an inch. On my f tuba. From what I've understood this is pretty large. So here's the thing. It's an American ($) shank Blokepiece piece on a Wessex Berg. Same shank on my Luzern (also Wessex) creates an even larger gap (.6+) Anyone experienced smaller than "standard" receivers on their wessex horns? Or maybe they're longer? Mark, have you measured your gap on your Berg?
All of this said, I'm still loving the setup with both my rigs...a lot!... just trying to figure out this gap business and if I've got some sort of smaller than standard receiver on my horns

Travis "'cause you can always make it better?"

Hi-
No need to measure....I like my Berg, after some other tweaking, just as is. Only thing I might do is to have lacquer stripped from bell.
Mark

PS The receiver on the Berg is larger than on my old CC Mirafone, but the mouthpiece(s) I use on each and results they give me are just dandy....

[toakstertuba]

Thanks for the replies. I totally get the if it ain't broke don't fix it thing, and like I said, I like what I've got going on. So, in terms of looking in the mirror, point taken. I actuality didn't even know what a gap was for my first 15 years of playing. I was curious what other's experiences with gap variances were, and if it'd be worth trying a different taper shank for fun, if not the possibility of even better response (articulation). After all, that's one of the fun parts about a 3 piece mouthpiece. .. which reminds me, Mr. Bloke, do you make smaller than American shanks?

[swillafew]

The distance from the end of the mouthpiece to the end of the receiver is what you are calling a gap?

I must be the person who never thought to measure this. Evidently Mr. Walters has met plenty who have.

What number is one hoping for?

[Michael Bush]

I read a little on a trumpet forum once

An excellent corrective exercise for anyone who thinks tuba players as a group obsess about equipment!

[toakstertuba]

Out of curiosity, can someone (different kind of horn) please measure the distance between end of receiver and "choke point" (where the lead pipe begins inside receiver) I used a paper clip to get mine. Maybe include what brand of horn? I'm curious to see if this initial distance is larger on my horn(s)...

[MaryAnn]

I would put forth a supposition that if a particular mouthpiece is a clear standout, that the gap it causes you to end up with is the right one for you. Whether that has more to do with it than the cup etc....would be fun for a nice long dissertation. That did happen for me with my horn; one particular mouthpiece, whose dimensions are not that different from some others, is a clear standout for tone, intonation, accuracy, etc. Is it the gap? I dunno, but it's fun to wonder about.

[opus37]

This subject was discussed a few years ago with the conclusion that gap matters. Here is the link to that discussion.

viewtopic.php?f=2&t=49125&hilit=gap" target="_blank

[MaryAnn]

Well, ok, now my curiosity is getting going. I'm not going to mess with my horn because it works very well with the piece I've used for many years, that came about when I took a box 'o pieces to a lesson, played them all for the teacher, and when I played a note on the current one he said THAT ONE. Both the piece and the bell are Lawson (both from when Lawson was Lawson) and both made a substantial difference in tone and slotting.

But my euph....I don't know what I don't know. I"m using a euro shank kelly 5G with blue tape on it to make it fit. (allergic to silver, gold is expensive, and the kelly works for me.) American shank barely even goes in, way too big; Euro shank without the tape is floppy. So.....tell this retired engineer how the gap is usually measured. I get how to measure (duh) how far the piece goes in, but lacking a lip or collar or something how would one know where one is measuring to for the start of the gap? The euph is a Sterling Perantucci and I can find no lip type thing inside the leadpipe. I saw a picture someone had of a pencil with an eraser but that did not compute anything for me. So ??

[Donn]

If your receiver is schematically like that, you should be able to detect an abrupt constriction somewhere back in there - the front of the leadpipe - and its depth is parameter a. Then insert the mouthpiece and measure how far it goes in, for parameter b. Answer is a - b.

Your receiver is not guaranteed to be like that, though. We use the acronym "AGR" for that - Ambiguous Gap Receiver.

[ edit - the very clear diagram thanks to David Werden ]

[Doug Elliott]

Exceptions: some tubas have the end of the leadpipe tapered to fit a mouthpiece, so there's no actual gap. Others have what I call a "reverse gap" where the start of the leadpipe is bigger than the receiver... sometimes considerably bigger. Some PT's I've measured are like that.

[MaryAnn]

I think I have the anonymous gap receiver. Oh well....the euph sits in the case for years at a time now anyway.

[Dan Schultz]

Doesn't Monette make a solid leadpipe/mouthpiece? I've seen pros playing trumpets that are made that way.

[toakstertuba]

Any chance anyone can get that measurement for me? I'm just needing the distance from the end of the receiver to where the lead pipe begins. I'd like to compare mine to some others out there. Thanks!

[Rick F]

I can't measure the gap for a tuba since I play euphonium, but wanted to contribute to this discussion.

On another forum there was a discussion about how the AGR works on the Adams euphonium. I was following the discussion and although I don't play an Adams, I was wondering if the gap — or lack there of — was causing my problems. In that discussion thread, a professional euphoniumist was trying out the new Adams E2. He was chipping a few notes of a familiar solo he'd played hundreds of times. Miel Adams suggested he try turning out the AGR a bit to add more gap. Bingo, no more chipping.

Recently I'd been having trouble with interval jumps in the upper register where I was chipping notes. We were playing "Il bacio" by Arditi with a very fine vocalist. The music was marked for one only, and I was the one playing. My mpc of choice was a G&W Kadja. During rehearsals I was chipping notes when jumping an octave or more. When I switched to the stock mpc for the M5050 that came with my horn (BT-16 by Demondrae Thurman), I had much better slotting. The Kadja shank seemed to be just a bit longer so maybe there is little or no gap. Also, the Kadja mpc has a chamfered edge on its shank. My slotting was much better with the Warburton BT-16.
___________________
Below are some additional points of that discussion thread:

Wide Gap (mouthpiece shank may be shorter):

• More Air Resistance
  Less Intonation Control
  Hard Slotting
  Less Flexibility
  Need Less Aperture Control

Medium Gap (Recommended):

• Medium Air Resistance
  Balanced Slotting & Flexibility

Small or Zero Gap (mouthpiece shank may be long):

• Less or No Air Resistance
  Considerable Intonation Control
  Loose Slotting
  Incredible Flexibility
  Need More Aperture Control

[Donn]

For those following at home -- I think this ^ was the first mention of the Adjustable Gap Receiver gimmick, "AGR". I was joking when I said that stands for Ambiguous Gap Receiver.

Also, length of shank determines how far the throat etc. are from the gap; width of shank at the small end determines how long the gap is. Fat shank = big gap / skinny shank = small gap.

[toakstertuba]

So I finally got around to measuring a non wessex horn from end of receiver to the beginning of lead pipe. I've found that my two wessex horns have about a half inch more space than a Meinl Weston tuba. So, I suspect my American shank mouthpiece goes just as far into other American receivers, but my setup creates a larger gap. Playing wise, I have no complaints, I'm only curious about the design. Please save any "Chinese quality" remarks for yourself as I am truly satisfied with these horns. Just looking for thoughts on why this distance seems larger than standard.
Thanks everyone!

[toakstertuba]

...

[Three Valves]

I'd hit it...