Stainless Steel Backbores

I am placing an order for a batch of backbores to be made for us at the end of May.

I expect to have stock on hand ready to send out by the end of June. THANKS!!!

We have had some really great feedback regarding our backbores and are starting the process of having our backbores machined in batches from Stainless Steel! To begin with, we will be producing our #5, #7, #9 & Lead-M backbores.

#5 Backbore - A Orchestral style backbore that will fill comfortable an familiar to most player. A good sound spread, good projection, and designed to balance well with a medium-deep or deep orchestral style cup. Designed also to work well on both C and Bb trumpet. Similar to backbores favoured by orchestral players like John Hagstrom and Thomas Hooten.

#7 Backbore - A Medium, all-rounder backbore that pairs well with any medium, medium-deep and medium-shallow cup. Centred and stable with a solid core sound that projects.

#9 Backbore - A medium tight backbore best suited for medium-shallow and shallow cups. Perfect for classical musicians who are looking for a good option for pops or situations where they switch to a shallower cup. Plenty of core sound with support and stability. When paired with a shallower cup, the sound is fat and full of core and some shimmer.

Lead-M Backbore - The Lead-M relatively open for a commercial backbore. It sits somewhere between a Warburton #5 and #6 backbore. It offers enough resistance to provide support when used with a shallower cup, without being restrictive. As far as lead trumpet sound concepts go, this design has Wayne Bergeron in mind,  once again favouring fatness, core and stability over laser beams. It's a backbore for lead players who care about sounding good in all registers because good lead trumpet players do a lot more than just play loud double As. This backbore is also slightly longer than  a standard backbore which helps with stability and pitch when used with a shallow cup.

Why Stainless Steel?

Stainless steel makes the manufacturing process much more difficult and is avoided by most manufacturers because it seriously increases tool-wear which introduces issues with costs and keeping parts accurate. Our approach to this is to use standard CNC-lathe machining for the external profile, but to have the internals of the mouthpiece produced using sinker-EDM technology. Sinker EDM is a non-contact thermal erosion process that uses extremely hot sparks to remove material. This makes it easier to achieve high-precision accuracy for the internal geometry of our backbores with high repeatability without having to worry about tool wear. The reason other manufacturers don't do this is simply because traditional backbore reaming is cheaper, easier and faster.

While brass has been the historical standard for brass instrument mouthpieces, stainless steel offers distinct, verifiable advantages rooted in materials science and acoustics. For modern mouthpiece production—especially when translating precise CAD geometries directly to finished Phoenix Brass products—stainless steel provides superior structural and acoustic performance.

It costs us more time and money, but the payoff for the player is significant. Here is why stainless steel is worth considering:

1. More Sound, Less Effort

Standard brass is relatively soft, meaning when you push air and sound waves through it, the metal slightly flexes and vibrates. That microscopic flexing steals your acoustic energy. Stainless steel is incredibly rigid. Because it doesn't flex in sympathy with the sound wave, it forces more of the sound energy straight into the horn.

• The Result: Faster response, a boost in core projection, and more bang for buck.

2. Improved Slotting

Because the internal walls of a steel backbore don't yield to air pressure, the acoustic "nodal points" of your sound wave remain locked perfectly in place. Trumpet players feel this as superior slotting. Your targets become more stable, meaning notes lock in securely across extreme dynamics and all registers.

3. Bulletproof Shanks

Every trumpet player has dropped a mouthpiece. With a standard brass backbore, even a minor drop can instantly dent the end of the shank. Even a tiny dent completely ruins the acoustic connection between the mouthpiece and your receiver's gap. Stainless steel is incredibly tough. You can drop it, bang it, and abuse it, and the shank is more likely to hold up. We don't recommend you try to play the back nine of your local golf course with these backbores, but if you treat it like any mouthpiece, it'll last a life time.

4. The Weight Myth

People assume stainless steel is a heavy, sluggish material. It’s actually the opposite—standard brass is denser than stainless steel. If we made the exact same backbore out of both materials, the steel one would be slightly lighter. We use this to our advantage. We intentionally design our stainless backbores with a slightly thicker wall profile (not where it would change the gap though). This gives you some of the benefits of a "heavyweight" piece (stability and and more core sound) without making the horn feel like you're driving a truck.

5.No Plating? No problem

Stainless steel is inherently safe, hypoallergenic, and highly corrosion-resistant. It requires no plating whatsoever. No tarnishing, no wear-and-tear, no compromises.