 The Clarinet BBoard
|
Author: golfnclarinet
Date: 2010-04-07 03:51
Remove the bell, put a cork(from wine bottle) in to lower end of lower joint and blow the air through barrel or upper joint with low E fingering.
This is how I’m checking leaks on my clarinet.
I feel little air is coming out of low two big pads(f#/c#, g#/d# pad) where spring is pushing pads.
But, I don’t see any leak with leak light.
Should it be 100% air tight?
Thanks in advance.
|
|
Reply To Message
|
|
Author: Tony F
Date: 2010-04-07 04:20
A better test is to suck rather than blow, and see how long it holds a vacuum. When you blow, air pressure can lift the pads against the springs. Leaks at the lower pads will cause problems in the high register, but will probably work OK in the low register. Try closing the pads using the keys normally while checking the seal of the pad with a sliver of mylar wrapping paper (from a candy bar or similar). Check 4 places around the pad, it should grip the mylar enough that there is some drag when you slide it out.
Tony F.
|
|
Reply To Message
|
|
Author: golfnclarinet
Date: 2010-04-07 04:33
When we play, we blow the air.
Even if I don't see or have any leak, if spring is not strong enough to hold the pads, it could cause the problem, especially on high notes.
So, I think spring needs to have right tension.
What's right tension?
This is my question.
Post Edited (2010-04-07 04:35)
|
|
Reply To Message
|
|
Author: GLHopkins
Date: 2010-04-07 05:02
If the lower joint leaks when blowing, excessive spring tension isn't necessarily the solution to the problem. The pads must be level with the tone hole. When the key closes the pad must touch at the same time all of the way around. I've been repairing for 30 years, and I don't use a light to check for leaks on a clarinet. I use a thin feeler gage. You can take a cassette tape, cut about 1" or so off...split that in half and then glue to a stick of some sort, or use a x-acto knife handle as a holder. Slip this between the pad and tonehole and lightly close the pad (pulling the feeler out) and feel at several points around the pad using the same pressure to close the pad all of the way around. It takes a while to develope a feel for this. Pads don't always feel the same when checking for leaks even if they are the same type of pad. Some techs think that a pad that sprung closed doesn't have to be a level as those that you close when playing. I'm not one. I want every pad as level as possible. I also want every tone hole surface to be completely free of flaws or blemishes.
A plastic clarinet could be tight enough so that it will hold a vacuum for a minute or so, but it's not necessary for it to be that tight to play well. A wooden clarinet doesn't have to pull a tremendous vacuum to play well either, but if you are going to go to the effort to do the job you need to do it as well as you possibly can.
Spring tension is another thing. I like a balanced feel to the keywork. You can get away with lighter spring tension if your pad work is flawless.
|
|
Reply To Message
|
|
Author: skygardener
Date: 2010-04-07 05:14
The question is- How hard are you blowing?
If you are using the same amount of force that you use when you play and there is some air coming out, there might be a small leak. If you really have to push a lot, there is no worry at all.
All clarinets will leak air if you blow hard enough.
|
|
Reply To Message
|
|
Author: clarnibass
Date: 2010-04-07 05:53
First, don't check the entire clarinet and instead check each joint seperately. You can suck and blow, but blowing is more real. Sucking won't necessarily mean much but worth trying, why not. With the lower joint, blowing hard enough will just blow open the two lowest closed pads. You will actually see them move.
When checking I prefer to squirt air from my mouth as opposed to actually blowing the air out. Was suggested this by Gordon (also posts on this forum) and found that this is more sensitive. If F#/C# and/or Ab/Eb blow open no matter what then use whatever way you can to check if they leak e.g. feeler, leak light (not so helpful with clarinets a lot of times), play testing middle B to D tremolo, checking middle B at pianisimo which is the most sensitive for any leak.
IMO the squirting method is so sensitive that it's possible to do with control of the correct amount. Block the end or have an assitant to close keys harder to check if they leak.
|
|
Reply To Message
|
|
Author: Paul Aviles
Date: 2010-04-07 10:15
I am a stickler for the right pinky Eb/Ab key to be just a bit more "sprung." If air leaks with minimal positive pressure, it WILL affect the sound when you play. Although, the first posting sounded as if there was A LOT of positive pressure.
...............Paul Aviles
|
|
Reply To Message
|
|
Author: Chris P
Date: 2010-04-07 10:59
The lower joint doesn't have to be as airtight as the top joint, though it still has to be sufficiently airtight.
The top joint should ideally be as airtight as if you're creating a vacuum in a Coke bottle.
Former oboe finisher
Howarth of London
1998 - 2010
The opinions I express are my own.
|
|
Reply To Message
|
|
Author: Paul Aviles
Date: 2010-04-07 12:14
Dear Chris,
I would just say I have had better experience on a clarinet with BOTH joints sealing "like a coke bottle."
There are many different threads on this already (whether some leakage is better for evenness of response) so I wil try not to start that again, but I have found that the clarinet generates more sound this way.
I've run into a few clarinets that played tentatively in the lower half and had an issue with the positive pressure with the Eb/Ab key, but once the spring tension was brought up a bit, the response came up markedly.
..................Paul Aviles
|
|
Reply To Message
|
|
The Clarinet Pages
|
 |
.jpg){kind=small}
.jpg){kind=small}
.jpg){kind=small}
.jpg){kind=small}
.jpg){kind=small}
.jpg){kind=small}
