Cup depth vs Backbore size

B
BrianJohnston
Posts: 1165
Joined: Jul 11, 2020

by BrianJohnston »

Hi all,

I've heard many comparisons about how changing the Cup size (depth) & the Backbore have basically the same effect on a mouthpiece.

so... I'm wondering if someone can shed the light on what the difference is in terms of feel, sound, etc. thanks
W
WilliamLang
Posts: 636
Joined: Nov 22, 2019

by WilliamLang »

I use a super deep cup (Euphonium mouthpieces have always felt good to me, and I'm currently on an LI Brass 550E piece with a 5g rim and about a 2g cup.)

I like the room it gives for the air to blow into the backbone, and I notice a much larger difference personally than I do on pieces that have larger backbores. On swallower cups with larger backbones I haven't felt as comfortable or sounded as good.

It does also seem like I'm a little bit of an outlier when it comes to cup depth though, like, I'll fight to the death for Shilke 51D being a good trombone mouthpiece lol.
H
harrisonreed
Posts: 6479
Joined: Aug 17, 2018

by harrisonreed »

Everything William said above, but the opposite conclusion for me. Shallow wide cup with a very open throat and relatively tight backbore. Plays huge for me.
P
Posaunus
Posts: 5018
Joined: Mar 23, 2018

by Posaunus »

[quote="WilliamLang"]It does also seem like I'm a little bit of an outlier when it comes to cup depth though, like, I'll fight to the death for Shilke 51D being a good trombone mouthpiece lol.[/quote]

I can't do it (51D is too deep for me) but I have a friend (really mostly a bass trombonist) who uses a Schilke 52E2 on his 0.547" bore tenor. Too much for me, but he's a big guy (majored in bass trombone / tuba / baritone).
S
ScottZigler
Posts: 26
Joined: Jul 19, 2023

by ScottZigler »

[quote="harrisonreed"]Everything William said above, but the opposite conclusion for me. Shallow wide cup with a very open throat and relatively tight backbore. Plays huge for me.[/quote]

Just curious, what are the specs on the mouthpiece you use on bass?
M
MBurner
Posts: 141
Joined: Mar 15, 2019

by MBurner »

In my experience:

Cup depth changes the angle of your airstream. Deeper means you have to adjust more to play high, easier to play low as the cup is already bigger.

Backbore and throat, changes the amount of air you have to use. Bigger throat, more air has to go through, bigger backbore, more open and more air. Surely the bigger it is, the slower the airstream must be because of the air volume difference. Bigger= more mellow or “darker” sound.

I too use large equipment, comparatively. I use a Greg Black NY3.5 for symphonic and solo playing, and a GB Alessi 1M or 2M at work, depending on part. That’s primarily mated to the horn I play. The deeper cup helps balance out the brilliance of the Bach bell I play symphonically, and the big deep heavy mouthpieces work well for the parade field on my dedwards, where you have to play pretty full to sound good at all.
L
LIBrassCo
Posts: 585
Joined: Feb 24, 2019

by LIBrassCo »

[quote="BrianJohnston"]Hi all,

I've heard many comparisons about how changing the Cup size (depth) & the Backbore have basically the same effect on a mouthpiece.

so... I'm wondering if someone can shed the light on what the difference is in terms of feel, sound, etc. thanks[/quote]

When thinking about the cup, depth is useless without context of the cup profile. Backbore influences a completely different set of characteristics.
H
harrisonreed
Posts: 6479
Joined: Aug 17, 2018

by harrisonreed »

[quote="ScottZigler"]<QUOTE author="harrisonreed" post_id="219840" time="1694532061" user_id="3642">
Everything William said above, but the opposite conclusion for me. Shallow wide cup with a very open throat and relatively tight backbore. Plays huge for me.[/quote]

Just curious, what are the specs on the mouthpiece you use on bass?
</QUOTE>

I was talking about my tenor mouthpiece up above.

My bass piece is very deep, 1.055" ID, and .312" throat. The throat length is pretty long. Because the ID is so narrow, the volume has to be made up by going deep. Totally different animal.
J
JeffBone44
Posts: 367
Joined: Oct 24, 2022

by JeffBone44 »

What's the difference between the throat and the backbore? I assume that the throat is the opening at the bottom of the cup?
B
BrianJohnston
Posts: 1165
Joined: Jul 11, 2020

by BrianJohnston »

[quote="JeffBone44"]What's the difference between the throat and the backbore? I assume that the throat is the opening at the bottom of the cup?[/quote]

The throat is the opening at the bottom of the cup, or the smallest opening in the mouthpiece that you can visibly see.

The Backbore is the inside of the shank.
C
CharlieB
Posts: 434
Joined: Mar 29, 2018

by CharlieB »

[quote="JeffBone44"]What's the difference between the throat and the backbore? I assume that the throat is the opening at the bottom of the cup?[/quote]

Yes, the throat is the opening you see at the bottom of the cup.

Its diameter may extend for an unspecified distance into the shank before it transitions into the (tapered) backbore.

Info here:

<LINK_TEXT text="https://hub.yamaha.com/winds/brass/guid ... backbores/">https://hub.yamaha.com/winds/brass/guide-to-brass-mouthpieces-part-3-throats-and-backbores/</LINK_TEXT>