Lead Pipe Optimisation –
A Case Study
Optimising the lead pipe of an existing
German C-trumpet to match intonation
and response of a reference instrument
by Rainer Egger & Wilfried Kausel
The Original Instrument (D3)
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German C-trumpet for a certain orchestra
Usually played with mouthpiece Bach C1½
Originally designed using BIOS
BIOS proposal for lead pipe was not followed
– lead pipe was designed according to
maker‘s experience
• Original instrument was good and accepted
(especially sound!) but exhibited some
weaknesses (response, intonation)
The Reference Instrument
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Different Maker
Different Design
Better intonation
Better response
Timbre less satisfying
Project Goal
Optimise lead pipe of D3 preserving its
timbre but resembling intonation and
response of reference instrument.
Optimise lead pipe for mouthpiece
Breslmair G1
Initial Optimiser View
Final Optimiser View
Modelling deviations
caused by cut-off frequency
Optimisation Targets
• Matching impedance envelope was the main
optimisation target!
• Matching the reference intonation was not
specified explicitly as intonation and
impedance envelope are not independent of
each other.
Evaluation of Optimised
Instrument by Players
• Optimised lead pipe was manufactured
twice with slightly different tolerances
• Blind evaluation was performed by
experienced trumpet players
• Preliminary results are very promising
Judgements about D3
(original state)
– Bad intonation (very flat in middle register)
– Much sound but instable in tone colour
– Too flexible, no pitch centre
– No stiffness
– Muddy (especially when played with G1)
– Slow feedback
Judgements about D3
(optimised lead pipe)
– Good intonation
– Less power but stable tone colour
– Less flexible, pitch very well centred
– Higher register easier (small differences
between both versions of new lead pipe)
– Easy attack / response
– Fast feedback
Summary
• Blind evaluation of new lead pipe by
several players confirms better
intonation as well as better response
• Good match between predicted
characteristics, measured characteristics
and subjective perception
• Project considered a full success by
customers