The Complete Cross-Brand Trumpet Mouthpiece Comparison Guide

If you've ever tried to find the equivalent of your Bach 3C in Schilke, or wanted to know what Yamaha model matches your Warburton setup, you already know the problem: there's no good answer anywhere online.

You get forum threads where five players give five different answers. You get manufacturer charts that only show their own models. You get comparison tables that mix up measurements from different reference points and present them as if they're the same thing.

This guide does it right. We'll explain why cross-brand comparison is genuinely hard, how to do it correctly using actual millimeter measurements, and give you the most complete cross-brand equivalency table available — covering Bach, Schilke, Yamaha, Warburton, Denis Wick, and GR for the most common trumpet mouthpiece sizes.

For any model not covered here, use Equivalent Finder — it ranks similar mouthpieces across brands in our database using measured specs. To compare two specific models side by side, use Compare.

Why Cross-Brand Comparison Is Harder Than It Looks

The obvious answer to "what's the Bach 3C equivalent in Schilke?" seems simple: find the Schilke mouthpiece with the same rim diameter and cup depth. Done.

The problem is that every brand measures differently.

Bach measures rim inner diameter from one reference point on the cup geometry. Schilke measures it from a slightly different point. Yamaha from another. So when you put a Bach spec sheet next to a Schilke spec sheet and compare the millimeter numbers, you're not always comparing the same thing — even when the measurement label says the same words.

This is why popular comparison charts often contradict each other. One chart says Bach 3C = Schilke 14C. Another says Bach 3C = Schilke 13C. Both authors measured carefully. They just measured differently.

There's a second problem: rim diameter and cup depth are not the whole story. Two mouthpieces with identical rim diameter and cup depth can feel and play completely differently if the rim contour, cup shape, or backbore differs. "Equivalent" almost never means "identical in every way." It means "close enough that the transition is manageable."

What this means practically: use cross-brand equivalency tables as a starting point, not a final answer. The table tells you what to try first. Your ears and your embouchure make the final call.

The Brands Covered in This Guide

Before the comparison tables, here's a quick overview of how each brand's naming system works. For an interactive decode of any model code, use the Mouthpiece Name Decoder. For a full playing guide that includes anatomy and choosing strategy, see The Complete Guide to Trumpet Mouthpieces.

Vincent Bach

The reference brand. Every other brand's models are typically described in relation to Bach. Bach uses:

• Number (1, 1.5, 2, 3, 5, 7, 10, 10.5, 12) → rim inner diameter. Lower number = larger diameter.
• Letter (A through F) → cup depth. A = deepest, F = shallowest. C is standard.
• "W" suffix → wider outer rim

So a Bach 3C has a medium-large rim and a standard-depth cup. A Bach 7C has a medium-small rim and a standard-depth cup. A Bach 3E has a medium-large rim and a shallow cup — the classic lead mouthpiece configuration.

Schilke

Schilke numbers run opposite to Bach. This trips up almost every player who switches brands for the first time.

• Number (6 through 21) → cup diameter. Lower number = smaller diameter.
• Letter (A through E) → cup volume. A = small, C = standard, E = large.
• Second number (1–5) → rim contour. 1 = roundest, 5 = flattest.
• Final letter (a through z) → backbore. a = tight, c = standard, d = medium large.

A Schilke 14C is a medium-large rim, standard cup — roughly comparable to a Bach 3C. A Schilke 11 is a medium-small rim, standard cup — roughly comparable to a Bach 7C.

When only a number appears on a Schilke (like "Schilke 14"), all other parameters are standard — it's shorthand for 14C3c.

Yamaha

Yamaha uses an entirely different scale:

• Number (5 through 68) → inner diameter. Higher number = broader rim.
• First letter (A through E) → cup depth. A = shallow, C = standard, E = deep. Note: this is reversed from Bach — in Bach, A is deepest; in Yamaha, A is shallowest.
• Second number (1–5) → rim contour.
• Final letter (a through e) → backbore taper.
• "TR" prefix → trumpet (distinguishes from cornet and flugelhorn models)

So a Yamaha 14D4 has a medium-large rim, medium-deep cup — again roughly comparable to a Bach 3C area.

Warburton

Warburton uses a modular system — you buy a rim and a cup separately and combine them. This is fundamentally different from every other brand.

• Rim number (2 through 13) → rim inner diameter. Lower number = larger diameter, like Bach.
• Cup code → depth and shape variant. M = standard, D = deep, MD = medium-deep, S = shallow, SV = screamer (very shallow).

So a Warburton 4MD is a medium-large rim with a medium-deep cup. A Warburton 7SV is a medium rim with a very shallow cup — one of the most popular lead mouthpieces on the market.

The modular system means you can mix any rim with any cup. Change genres, change the cup. Keep the rim the same so your embouchure doesn't have to adapt. This is why professionals who play multiple styles often use Warburton.

Denis Wick

The dominant brand in the UK and European brass band market. Denis Wick uses a numbering system similar in logic to Bach — lower numbers = larger sizes. Strong presence in orchestral and brass band contexts. Numbers run roughly 1 through 6 for trumpet.

GR (Gary Radtke)

GR uses a numerical system that approximately expresses inner diameter in hundredths of inches:

• GR 64 ≈ 0.640" inner diameter → roughly Bach 7 size
• GR 65 ≈ 0.650" → roughly Bach 5 size
• GR 66 ≈ 0.660" → roughly Bach 3–5 area
• GR 67 ≈ 0.670" → roughly Bach 3 area
• GR 67.4 ≈ 0.674" → roughly Bach 1.5C area

Cup depth follows with a letter: M = medium, L = large, S = small/shallow, XL = extra large.

GR mouthpieces are expensive ($150–$300+) and primarily used by serious players who want precision. Players consistently report excellent slotting and intonation.

The Master Cross-Brand Equivalency Table

This table covers the most common trumpet mouthpiece sizes. Use it to find your starting point when switching brands.

How to read this table:

• Each row represents a size/depth combination
• All equivalencies are approximate — small differences in rim contour, cup shape, and backbore mean "equivalent" is never "identical"
• Similarity is highest within each row for rim diameter and cup depth; other variables may still differ
• For ranked matches from our database, use Equivalent Finder

Standard Cup (C-depth equivalent) — Most Common

Shallow Cup (Lead / Commercial) — D and E depth equivalent

Deep Cup (Orchestral / Dark Tone) — A and B depth equivalent

The Most Common Switching Scenarios

Switching from Bach to Schilke

This is the most common brand switch in the trumpet world. The main trap: Schilke numbers run opposite to Bach. A player moving from Bach 3C who grabs a Schilke 3C will end up on something much smaller than they're used to.

The correct moves:

What to expect: Schilke mouthpieces are machined to tighter tolerances than Bach. Players switching from Bach to Schilke often report the Schilke feels more precise and consistent, with slightly better intonation in the upper register. The tone is often described as a bit cleaner and more focused than Bach — slightly less "spread." Whether that's better for you depends on what you're playing.

Switching from Bach to Yamaha

Yamaha produces some of the most consistent mouthpieces available at any price point. The quality control is excellent — what you get will match the spec sheet closely.

Yamaha cup letter note: In Yamaha's system, cup letters run opposite to Bach. Yamaha A = shallow, Yamaha C = standard, Yamaha E = deep. Bach A = deep, Bach C = standard, Bach F = shallow. Don't assume a Yamaha C matches a Bach C in depth — check the actual mm measurement in the database.

Switching from Bach to Warburton

The biggest adjustment when moving to Warburton isn't the specs — it's the modular system. You're buying a rim and a cup separately. This is unfamiliar at first but becomes an advantage quickly.

The Warburton advantage: Once you have a rim you like, changing your sound profile is cheap — buy a new cup ($40–$60) rather than a whole new mouthpiece. Players who double on different styles often keep one rim and swap between a standard cup for mainstream playing and a shallow cup for lead work.

Switching from Schilke to Bach

Going the other direction — perhaps the most confusing switch because of the inverted numbering.

Finding a Discontinued Mouthpiece Equivalent

Older players returning to the horn often have a mouthpiece they loved that's been discontinued. The most common cases:

Heim / Gustat mouthpieces — these were standard mid-20th century orchestral pieces. Miles Davis famously used a Heim 2. If you're looking for a modern equivalent: Heim 2 → try Bach 3B or Schilke 14D.

Old Conn mouthpieces — frequently found in vintage cases. Generally medium sizes. Try Bach 3C or 5C as a starting point.

Jet-Tone mouthpieces — popular in the 1950s–70s lead/commercial world. Try Warburton lead cups or Schilke A-cup models.

If you have an old mouthpiece with worn-off markings, measure the inner rim diameter with a caliper and use Equivalent Finder or the database to narrow candidates by measurement rather than by model name alone.

Why "Equivalent" Is Never "Identical"

Even when the rim diameter and cup depth match closely, two mouthpieces from different brands can play and feel differently. Here's why.

Rim contour varies independently

A Bach 3C and a Schilke 14C have similar inner diameters and cup depths, but the rim contour — how curved the rim cross-section is — differs. Schilke's standard rim (contour "3") is slightly flatter than Bach's standard rim. Players with sensitive embouchures feel this difference immediately. Players who've been on Bach for years sometimes prefer Bach's rounder rim feel.

Cup shape within the same depth category varies

Two mouthpieces can have the same cup depth in mm but different internal cup profiles. One might have a more pronounced shoulder (the transition from cup wall to throat), creating a slightly different response. This is harder to measure and rarely documented on spec sheets — it's something you feel.

Backbore varies independently

The backbore is rarely matched in cross-brand comparisons. A Bach 3C has its own backbore character. A Schilke 14C has a different one. Both are "standard" — but standard means different things at each company. Players notice this as a difference in resistance feel and upper register response.

What this means for your switch

When you switch brands and the equivalent feels "almost right but not quite," it's almost always one of these three variables — rim contour, cup shoulder, or backbore — that's responsible, not the rim diameter or cup depth. That's the starting point for fine-tuning: stay in the same size range but explore contour and backbore variations within the new brand.

How to Evaluate a New Mouthpiece Fairly

Cross-brand switches fail most often because players evaluate too fast. Here's the right timeline.

Days 1–3: Everything feels different. This is adaptation, not incompatibility. The mouthpiece geometry is different and your embouchure is adjusting. Do not make any judgment.

Week 1: Things start to stabilize. You're getting a feel for the new resistance, the new slot. Still too early to judge tone or range.

Weeks 2–3: This is where real evaluation begins. Your embouchure has largely adapted. Now record yourself playing a range of material — low register, mid register, upper register, soft playing, loud playing. Compare the recording to your playing on your old mouthpiece.

Week 4: Final decision point. If after four weeks of consistent daily playing the new mouthpiece is not serving you as well as your old one, it's not the right fit. Go back.

The blind test: The most reliable evaluation is to have a player or teacher with good ears listen while you alternate between two mouthpieces without telling them which is which. What they hear from the front of the horn is more reliable than what you feel from behind the bell. You are always biased toward whatever you're currently comfortable with.

The Spec Variables That Matter Most — Ranked

When evaluating equivalency, not all spec differences are equal. Here's how much each variable matters for the overall feel and sound:

1. Rim inner diameter — the most important variable. Even a 0.5mm difference is significant. This is what most players adapt to most consciously.

2. Cup depth — the second most important variable for tone character. Deep vs. shallow is audible immediately. Small differences (0.3mm) are subtler.

3. Backbore — has a large effect on resistance feel and upper register. Harder to measure and less documented across brands, but very significant.

4. Rim contour — affects comfort and embouchure efficiency. Round vs. flat rims feel meaningfully different even at the same inner diameter.

5. Cup shape profile — the internal shape of the cup wall. Affects response and articulation more than tone. Hard to quantify.

6. Throat diameter — least variable across standard mouthpieces. Most are within ±0.1mm of standard. Significant only in custom or specialty designs.

A Word on Mouthpiece Marketing

Every mouthpiece manufacturer claims their product will improve your tone, extend your range, increase your endurance, and improve your intonation. Some of these claims are true in specific contexts. None of them are universally true.

Be skeptical of:

• Any claim that a mouthpiece "adds range" — range comes from technique
• Testimonials from professional players — professionals are often sponsored and their results reflect years of development on that mouthpiece, not the mouthpiece itself
• "Revolutionary design" language — most mouthpiece geometry has been understood for over a century
• Comparisons that only show the best-case scenario (bright tone comparison, always showcasing high notes)

The honest reality is this: at comparable quality levels, most standard mouthpieces in the same size range play more similarly than differently. The differences are real but they're measured in degrees, not orders of magnitude. A Schilke 14C and a Bach 3C are not night-and-day different instruments. They're variations within the same size range, each optimized slightly differently.

The biggest differences come from:

1. Significant size changes (going from a 7C to a 3C is a real change you'll feel)
2. Cup depth category changes (moving from C to A depth is a real change you'll hear)
3. Backbore changes (going from tight to open is a real change in resistance)

Small variations within a size category — the difference between a Bach 3C and a Schilke 14C — are real but subtle. Give any switch enough time and you'll adapt.

What to Do Next

You now have a complete framework for cross-brand comparison — how the naming systems work, why equivalency is approximate, and a reference table covering the most common models.

Find your specific equivalent:
→ Use Equivalent Finder — pick your reference mouthpiece and get ranked matches based on measured specs.

Compare two models in detail:
→ Use Compare for side-by-side specs and playing-characteristic notes.

Understand specs and choosing strategy end-to-end:
→ Read The Complete Guide to Trumpet Mouthpieces.

Not sure what direction to go?
→ Use the Mouthpiece Advisor — instrument, genre, goals, and optional current mouthpiece.

Decode a model name:
→ Mouthpiece Name Decoder.

Part of the mouthpiececomparator.com series. Related: Complete Guide to Trumpet Mouthpieces. More articles coming on the blog.