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rowuk · 03-28-2008, 08:19 AM

I think that maybe my post might not be in the correct perspective. Naturally, any changes to a leadpipe will do "something". Reversing it does "practically" nothing though.

Why? the length and geometry of the tuning slide does not "change" What happens is that we have a conical part, then the tuning part which both stay the same length and shape in both cases. The small step caused by the tuning slide not being pushed all the way in moves about 2" away from the mouthpiece on the reversed configuration. The proportions of tapered to cylindrical do not change one bit AND the effect of that step MAY change the response of one or two notes whose nodes happen to occur at those steps.
Many years ago, I experimented with my Bach C trumpet (229H large bore). We moved the bell brace back first. BIG difference! The horn seemed to play more responsively BUT did not have the projection OR dynamic range (it produced a lot more edge at lower volumes).
We then reversed the tuning slide, being careful to not create any solder blobs in the horn. Essentially NO tonal or blow difference.

Granted, this is not incredibly scientific, but makes my point. Small changes to the cylindrical parts of the horn do NOT make a big difference. Moving braces can make or break the design! A comparison of the two technologies is only valid when we use the exact same leadpipe and slides.

Brekelfuw bought a cheap horn and modified it in another thread. He also turned it into a reversed pipe model using EXACTLY THE SAME PARTS. The outer sleeve of the tuning area was moved to the slide and the inner part was soldered to the leadpipe. Essentially NO change in bore or taper except for that small step.

Eclipse and other companies with tuning bell models avoid this discussion by ELIMINATING the step entirely between the mouthpiece and valve block. The step gets moved between the valves and bell where it is acoustically less significant. This is a real design improvement in my opinion. A disadvantage is not having a solid fixed brace going to the front of the bell.

03-28-2008, 08:19 AM	#8 (permalink)
rowuk Moderator Fortissimo User Join Date: Jun 2006 Location: Germany Posts: 4,640	Re: Reversed Leadpipe I think that maybe my post might not be in the correct perspective. Naturally, any changes to a leadpipe will do "something". Reversing it does "practically" nothing though. Why? the length and geometry of the tuning slide does not "change" What happens is that we have a conical part, then the tuning part which both stay the same length and shape in both cases. The small step caused by the tuning slide not being pushed all the way in moves about 2" away from the mouthpiece on the reversed configuration. The proportions of tapered to cylindrical do not change one bit AND the effect of that step MAY change the response of one or two notes whose nodes happen to occur at those steps. Many years ago, I experimented with my Bach C trumpet (229H large bore). We moved the bell brace back first. BIG difference! The horn seemed to play more responsively BUT did not have the projection OR dynamic range (it produced a lot more edge at lower volumes). We then reversed the tuning slide, being careful to not create any solder blobs in the horn. Essentially NO tonal or blow difference. Granted, this is not incredibly scientific, but makes my point. Small changes to the cylindrical parts of the horn do NOT make a big difference. Moving braces can make or break the design! A comparison of the two technologies is only valid when we use the exact same leadpipe and slides. Brekelfuw bought a cheap horn and modified it in another thread. He also turned it into a reversed pipe model using EXACTLY THE SAME PARTS. The outer sleeve of the tuning area was moved to the slide and the inner part was soldered to the leadpipe. Essentially NO change in bore or taper except for that small step. Eclipse and other companies with tuning bell models avoid this discussion by ELIMINATING the step entirely between the mouthpiece and valve block. The step gets moved between the valves and bell where it is acoustically less significant. This is a real design improvement in my opinion. A disadvantage is not having a solid fixed brace going to the front of the bell. __________________ Whenever I feel blue, I start breathing again. Last edited by rowuk; 03-28-2008 at 08:22 AM.