Lew, "original" or "period" instruments refers to the
instruments that were in use when the particular music was composed and
applies primarily to the music of the Rennaisance and Baroque and, as you
say, the early to mid-Classical period. These may be early, less evolved
versions of instruments that we know today or intruments no longer in use
other than in early-music ensembles and no longer manufactured. By the
late 19th century most orchestral instruments had evolved in design to
essentially what they are today; relatively subtle design improvements
continue until the present. String instruments have evolved with increased
power and volume as a primary goal, brass and ESPECIALLY woodwinds
have evolve with ergonomic improvements as a primary goal in order to
facilitate the higher technical demands of more modern music composition
styles. Early woodwinds were very crude in comparison to modern
versions which have evolved to have much more ergonomic and advanced
key mechanisms and improved tuning. For instance, the chalumeau, the
predecessor of the clarinet used only two or three keys as opposed to the
modern Boehm system clarinet. Clarinet parts found in the modern
orchestral repertoire would be impossible to execute on a chalumeau.
Re vibrato: the instrument does not determine wether vibrato is used or not;
it is a technique that a player chooses to use (or not) depending on wether
the player feels it is musically appropriate or not. You are correct, the
trumpets used by Dizzy and Marsalis, while by different maufacturers, are
not fundamentally different, the instrument has not seen fundamental
design changes for quite some time, although Marsalis' "Monet"
trumpet, a very expensive ultra-high end custom instrument, in theory, has
some subtle design improvements incorporated. In theory, because these
"improvements" are not universally appreciated by musicians.
An interesting parallel between this subject and the audiophile world is that
with the advent of computer programs and analysis used in the design of
modern instruments, in order to "improve" aspects of an
instrument's character, some designers now use less of the old school
method of "if it sounds good, then it must be good" approach
and rely more on technical theory. The end result has been some real
improvements particularly in the area of tuning; but, because
"theory" often conflicts with nature's laws of acoustics and
resonance, attempts to "fool Mother Nature" in the design
process often results in compromises in those hard-to-define aspects of an
instrument's sound and personality. Many modern players prefer
instruments designed before the advent of computer modeling.
