Posted by Lew on July 18, 2001 at 09:04:30:
In Reply to: Using the 5th valve posted by Dick on July 18, 2001 at 08:34:16:
I depends on what type of 5th valve it is. I believe that a "flat" whole step is the most common 5th valve configuration. If that is what it is you can think of it as an extra 1st valve to help with intonation, primarily in the low range. For example, if your Eb just below the staff is sharp, you could use the 5th valve instead to avoid pulling the first slide. It can also help with the D below that, 2+5, or the Db, 1+5. Also, 2+3+5 can be better in tune on BB (natural) than 2+4.
The most common use however is to help make the extended low range easier to play and better in tune. You can use 1+5 instead of 2+3 for GGb, 2+3+5 instead of 2+4 for EE (4 ledger lines), 4+5 for EEb instead of 1+4 (or 1+2+4 which is usually necessary to get this in tune). Continue down the same way to low BBB which 1+2+3+4+5 can usually get pretty much in tune. Experiment with different alternate fingerings in the pedal range to see what works for you.
Any of the other 5th valve configurations would require different combinations, but are essentially the same concept. i.e. extra tubing is added to one of the standard 3 valve combinations to allow that valve by itself or in combination with others to bring certain notes in tune or to be added to other valves to make the low range easier to reach.