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| STEP 1 We started with the easy task of unsoldering the brace between the bell and first valve slide. Observations: again, the horn is more free blowing with the brace removed! |
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| STEP 2 I have been aligning up-stroke and down-stroke of the piston valves with pleasing results. I wanted to take it one step further, to align the valves also laterally. On Jason's horn, the 2nd and 3rd valves were mis-aligned by slightly more than 1 mm while the 1st valve is mis-aligned by less than 1 mm. It may not seems much but nevertheless I would still like to see what the effect of lateral alignment is. To align the valves laterally, the spring barrel has to be soldered off and re-soldered in the correct position. Quite a difficult task! |
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| Observations:
the horn was play tested after each valve being aligned. It is obvious
that when a valve is aligned both vertically and laterally, pitch is
much easier to hold. Less inclined to go sharp or flat when you change
dynamic. |
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| STEP 3 For this horn, we started with the braces on the bell. Like in previous project, the bell was detached and the positions of the braces decided one after the other. The brace on the second valve casing was taken off. Observations: interestingly, the best resonance is obtained when the brace is placed on the 3rd valve casing, the original 2nd valve casing will also work but a first valve position is not good on this horn. (Compare to my first project, where the brace is best at the 1st valve casing!) |
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Looks like a custom fitting for each individual horn may be necessary for Bach trumpets. |
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| STEP 4 During the course of the project, I am fortunate enough to locate a small supply of some old original Bach brass valve guides from a repair shop. These been in storage for a few decades! Needless to say we try them out immediately. Observations: The response and tone of the horn is improved tremendously by replacing the nylon valve guides with the brass ones! (Why the factory changed to nylon guides then???) |
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| STEP 5 Next I tried out the positions of the mouthpiece receiver and determined the best position for it. Observations: again I have to pull out the mouthpiece receiver a bit, but not as much as I did in the previous project. I cannot predict the reason for it yet. Perhaps every horn is different but Richard and Jason are using different size mouthpieces. If the latter is true, we should discard the assumption that you can stick any mouthpiece into any horn! |
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| STEP 6 The finger hook and upper tuning-slide receiver are then soldered off and worked on. |
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| Observations:
the horn plays correctly only when the tuning-slide receiver and the
tuning slide is in perfect alignment. The position of the finger hook
and the supporting rod has a little effect on the sound and response. I
ended up placing
the finger hook and the rod both a bit forward than the factory
installed
position. |
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| STEP 7 The last step in working with this horn was to adjust the brace between the 3rd valve slide and the lower tuning slide receiver. |
 Jason play testing for final adjustment of the brace. |
| Observations: The effect of different brace positions became less and less obvious as the project progressed. We did notice a slight difference with this last brace we worked on, but the effect is nearly negligible. Nevertheless, we moved the brace forward quite a bit. |
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| After more than 3 months (the project ran from
September to December 2002!), Jason can finally play on his horn again.
Jason is happy with a more responsive instrument and he is able to add
a few notes to his range! |
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| More projects on the way...... |
|
 Project #1 |
Project #3 |
| Kenneth's Homepage |
