RT (Reverse Taper) Backbores
The RT lead trumpet backbore line was developed with player feedback from professional and non-professional players. The RT design produces a resistance which tends to be more predictable and secure at high volume levels.
Cutaway view of RT backbore
This drawing is exaggerated to better show the converging angles in a reverse taper backbore.
Bernoulli's Principle
When a moving fluid encounters a constriction, the velocity is increased.
Coanda Effect
The tendency of a jet of fluid (or gas) emerging from an orifice to follow an adjacent flat or curved surface.
The RT backbore line is designed with the commercial player in mind. The bore (venturi) size is designated with two numbers. The first number states the bore size at the interface (top) and the second number states the size at the apex.
RT1
The RT1 Lead Trumpet Backbore was inspired by the West Coast “studio” sound. It is small internally. If you are able to play a Schilke A backbore or a Reeves 692sL, you’ll love this one for its firm even resistance across all registers. The bore is #27 at the interface and #30 at the apex. As you overcome the resistance of the RT1 the payoff is in efficiency and projection. Its intense focus makes it ideal for studio recording and mic’d live performances.
RT2
The RT2 Lead Trumpet Backbore is the flagship model of my line. After working with hundreds of lead trumpet players over the years I can say that I have a good idea of what they are looking for in a backbore. That would be a backbore which produces a bright projecting burn in the sound and energizes quickly into the blow. The RT2 is an exceptionally good match with shallow and extra shallow cups, and its high output assists lead players in broadcasting their intentions to the rest of the band. Bore: 27>29
RT3
The RT3 Lead Trumpet Backbore opens quickly and takes advantage of the full length of the backbore to develop a full sound reminiscent of the big band era – acoustically loud for projecting to the back of the hall without the assistance of a microphone. The resistance is comparable to the Warburton #6 or Reeves #2 backbores. The RT3 has a solid core, but will allow you to go “wide” when the music calls for it. Bore: 27>28
RT4
The RT4 Lead Trumpet Backbore is for the lead player who prefers less resistance from the mouthpiece. The large main backbore area is offset and balanced at the venturi, making use of the reverse taper for a quick compress/release. The result is a “fat” sound with the speed and response of an efficient backbore. Bore: 27>29
RT5
The large cavity of the RT5 proves that a backbore doesn’t have to be tight to produce a bright commercial sound. Slotting is not overly tight to allow more room for expression of your lead style. If you need to be facile in the upper register but do most of your work in the “cash” register, this one is for you. Bore: 27>29 (Don’t let the numbers fool you)
GG
The GG backbore has a clean “front” to the attacks and is a little wider in scope coming out of the bell. It produces an exciting lead sound but is also highly regarded by jazz players who use the full range of the trumpet. The resistance falls in between the RT2 & RT3. Bore: 27>29
TKO
With a similar resistance to RT2, the TKO backbore produces a commanding core with a fair amount of “teeth” in the sound. It has become my backbore of choice for loud cover band gigs. Bore: 27>30