• FAQ  • Search  • Memberlist  • Usergroups   • Register   • Profile  • Log in to check your private messages  • Log in 

Valve compression question



 
Post new topic   Reply to topic    trumpetherald.com Forum Index -> Cornet/Flügelhorn
View previous topic :: View next topic  
Author Message
ChuckK
Regular Member


Joined: 20 Aug 2020
Posts: 33
Location: Cincinnati, Ohio USA

PostPosted: Sat Dec 19, 2020 6:43 am    Post subject: Valve compression question Reply with quote

Is there any way to check valve compression on an instrument with stuck valve slides?
_________________
Never confuse beauty with things that put your mind at ease. - Charles E. Ives
Back to top
View user's profile Send private message AIM Address
zaferis
Heavyweight Member


Joined: 03 Nov 2011
Posts: 1936
Location: Beavercreek, OH

PostPosted: Sat Dec 19, 2020 7:21 am    Post subject: Reply with quote

Trying not to come off too snarky.. but what are the reasons for stuck slides: poor manufacturing, lack of care, or injury. How about getting the slides to work properly - then worry about compression?
If there's a vacuum pop when you pull the slides - you'll have a sense of the compression.
Maybe the compression of the valves is the last thing that needs attention, kind of a rare and unusual starting point of concern....
_________________
Freelance Performer/Educator
Adjunct Professor
Bach Trumpet Endorsing Artist
Retired Air Force Bandsman
Back to top
View user's profile Send private message
JayKosta
Heavyweight Member


Joined: 24 Dec 2018
Posts: 1485
Location: Endwell NY USA

PostPosted: Sat Dec 19, 2020 7:23 am    Post subject: Reply with quote

Use an extra heavy oil on the pistons - so valve action is sluggish, that oil will be a good seal to simulate a 'tight valve job'.
Do simple playing using all the valve combinations, and try to detect any changes.
If you think there 'might be' an improvement, then wrap 5 $100 bills around the valve casings and try again ...
_________________
King Super 20 (S2 1048, HN White)
Bach 7
The 'next note' is the most important one.
Don't take a '20 minute mouthpiece' to a 1 hour session.
http://users.hancock.net/jkosta/2020_Dec_17_Snow_2_small.jpg
Big Snow 1 week before Christmas
Back to top
View user's profile Send private message
ChuckK
Regular Member


Joined: 20 Aug 2020
Posts: 33
Location: Cincinnati, Ohio USA

PostPosted: Sat Dec 19, 2020 7:46 am    Post subject: Reply with quote

zaferis wrote:
Trying not to come off too snarky.. but what are the reasons for stuck slides: poor manufacturing, lack of care, or injury. How about getting the slides to work properly - then worry about compression?
If there's a vacuum pop when you pull the slides - you'll have a sense of the compression.
Maybe the compression of the valves is the last thing that needs attention, kind of a rare and unusual starting point of concern....


Well, in trying to evaluate a used instrument that I might be interested in buying, I'd like to know the condition. If the slides are stuck then that means about a hundred in repair bills to clear them, plus a chem cleaning would be wise. That might be OK if the horn is worthing of owning and playing, but if the valves are 'wobbly' that's about another $500 in repair and puts the whole thing out of bounds financially.
_________________
Never confuse beauty with things that put your mind at ease. - Charles E. Ives
Back to top
View user's profile Send private message AIM Address
zaferis
Heavyweight Member


Joined: 03 Nov 2011
Posts: 1936
Location: Beavercreek, OH

PostPosted: Sat Dec 19, 2020 12:21 pm    Post subject: Reply with quote

ChuckK wrote:
zaferis wrote:
Trying not to come off too snarky.. but what are the reasons for stuck slides: poor manufacturing, lack of care, or injury. How about getting the slides to work properly - then worry about compression?
If there's a vacuum pop when you pull the slides - you'll have a sense of the compression.
Maybe the compression of the valves is the last thing that needs attention, kind of a rare and unusual starting point of concern....


Well, in trying to evaluate a used instrument that I might be interested in buying, I'd like to know the condition. If the slides are stuck then that means about a hundred in repair bills to clear them, plus a chem cleaning would be wise. That might be OK if the horn is worthing of owning and playing, but if the valves are 'wobbly' that's about another $500 in repair and puts the whole thing out of bounds financially.


Ask that question then... Thicker oil on the valves-does it play differently/better.? Do you like the sound, intonation, brand/reputation? Then, you're taking your chances on overhaul costs.. good luck
_________________
Freelance Performer/Educator
Adjunct Professor
Bach Trumpet Endorsing Artist
Retired Air Force Bandsman
Back to top
View user's profile Send private message
Beyond16
Veteran Member


Joined: 07 Jan 2020
Posts: 144
Location: Coronaville, TX.

PostPosted: Sat Dec 19, 2020 5:45 pm    Post subject: Re: Valve compression question Reply with quote

ChuckK wrote:
Is there any way to check valve compression on an instrument with stuck valve slides?


Easy. Plug the bell with a rubber ball and pressurize the horn with your mouth. See how slowly the air leaks out. Compare the result to a different horn. Repeat with all valves closed.
Back to top
View user's profile Send private message Visit poster's website
Bflatman
Heavyweight Member


Joined: 01 Nov 2016
Posts: 593

PostPosted: Mon Dec 21, 2020 2:03 pm    Post subject: Reply with quote

Sealing the bell with a rubber ball is the way to go.

Blowing into the instrument with all valves depressed then mimics the compression test.

I now offer a word of caution.

A valve compression test is only useful if you already know whether you prefer or need looser or tighter valves.

No instrument can be pressurised without a rubber ball stuffed in the bell therefore the trumpets ability to hold compression demands that it be rendered unplayable.

Some players prefer tight valves some prefer looser valves.

As a blues musician I much prefer looser valves. Having said that I dont have an instrument with loose valves so I have to put up with valves that are tighter than my preferred ideal.

The only real measure of whether the valves are acceptable is how it plays and the ease with which you can achieve musically what you need to do.

What to look for is note pitch centering, does the note center strongly or is the note slippery and require good control to play each note on pitch.

I have seen an instrument with valves so loose that full octave glissades are ridiculously easy to perform just by lipping but playing a tune that is recognisable is ridiculously difficult to do.

The offending instrument was a cornet made around 1870 by an unknown builder and it is not known if this instrument ever had remotely tight valves.

It has to be said that old instruments with no finger ring or thumb saddle need loose valves.

Many old instruments have fixed slides that can be adjusted once at the beginning of play and they have no adjustment ring or saddle so lipping notes is demanded during play or you cannot play in tune for those notes that demand an extended slide.

In other words if you have an old instrument with no finger ring or thumb saddle it was designed to have looser valves and be lippable to have good intonation.

Giving such an instrument a valve job can destroy its usefulness and also its flexibility and gives it intonation problems.

For me only the music matters be driven by the music and how easy it is to perform the way you need to.

I know of one pro quality player who was seduced by a low compression test and well meaning advice to have a valve job done and he loved the instrument before the valve job but could not play the instrument to anything like the standard he was capable of after the valve job.

In other words he ruined the instrument with the valve job.

Make your decision after extensively playing the instrument and know what a valve job will give you and what it will take away.
_________________
Conn 80a Cornet
Boosey & Hawkes Emperor Trumpet
Olds Fullerton Special Trumpet
Selmer Invicta Trumpet
Yamaha YCR 2330II Cornet
Selmer Student Trumpet
Bohland and Fuchs peashooter Trumpet
Boosey and Hawkes Regent Cornet
Lark M4045 Cornet
Back to top
View user's profile Send private message
James Becker
Heavyweight Member


Joined: 02 Sep 2005
Posts: 2786
Location: Littleton, MA

PostPosted: Wed Dec 23, 2020 8:02 am    Post subject: Reply with quote

In my view, worn leaking valves are equivalent to badly worn steering ball joints. Slippery pitch center to me is much like too much lash in your steering wheel. How well your instrument tracks is not so different than a car that drifts when your steering is no longer tight. Immediacy of response is reduced due to the loss of efficiency. There are other places in the bore, i.e. reduced mouthpiece receiver gap or larger bell tapers that contribute a wider pitch center without having leaking valves. These are part of an instrument’s over all design, and can exist with valves that are airtight.

Though not a cornet, Boston Symphony principal trumpet, Tom Rolfs does not care for his Bach trumpets having the standard 1/8” (.125”) gap. Rather, he prefers a gap in the range of .090” to .100”. This allows him greater pitch flexibility without loosing too much pitch center. Tom described the feeling of getting further into the note. Coincidentally, the Yamaha Artist trumpet he now plays comes standard with .100” gap. So you see, flexibility of pitch can be achieved without sacrificing efficiency.

My two cents.

And another thing many of you may or may not be aware. Subtle changes in water key pad material and screw tension can providing lesser or greater pitch center and firmness of articulations. Some additional food for thought. Discuss....
_________________
James Becker
Brass Repair Specialist Since 1977
Osmun Music Inc.
77 Powdermill Road Rt.62
Acton, MA 01720
www.osmun.com

Our workshop is as close as your nearest UPS store https://www.ups.com/dropoff?loc=en_US
Back to top
View user's profile Send private message Send e-mail Visit poster's website AIM Address
Display posts from previous:   
Post new topic   Reply to topic    trumpetherald.com Forum Index -> Cornet/Flügelhorn All times are GMT - 8 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group