Bach vs Kelly Trombone Mouthpieces
Bach offers 74 trombone mouthpieces (made in United States), while Kelly has 17 models (made in United States). On average, Bach cups measure 25.40mm versus 25.86mm for Kelly. Below we compare both lineups side by side to help you choose the right brand for your playing style.
Bach
Models74
Avg cup25.40mm
Avg throat6.40mm
Common style—
CountryUnited States
vs
Kelly
Models17
Avg cup25.86mm
Avg throat—
Common styleBass
CountryUnited States
Bach vs Kelly — head-to-head comparisons
- Bach 1¼G vs Kelly 12C
- Bach 1¼G vs Kelly 6-1/2AL-LS-SS
- Bach 1¼G vs Kelly BASS-BONE-LS-SS
- Bach 1¼G vs Kelly SKY-SS
- Bach 6½AL (large shank) vs Kelly 12C
- Bach 6½AL (large shank) vs Kelly 6-1/2AL-LS-SS
- Bach 6½AL (large shank) vs Kelly BASS-BONE-LS-SS
- Bach 6½AL (large shank) vs Kelly SKY-SS
- Bach 12C vs Kelly 12C
- Bach 12C vs Kelly 6-1/2AL-LS-SS
- Bach 12C vs Kelly BASS-BONE-LS-SS
- Bach 12C vs Kelly SKY-SS
All models
Bach (74)
1¼G
27.50mm · V.Deep
6½AL (large shank)
25.40mm · Deep
12C
24.50mm · Shallow
12E
24.50mm · Shallow
5GS (large shank)
25.50mm · Deep
6½A (small shank)
25.40mm · Deep
6½AL (small shank)
25.40mm · Deep
15D
24.40mm · Shallow
4G
26.00mm · V.Deep
5G (large shank)
25.50mm · V.Deep
7C
24.75mm · Shallow
Mega Tone Trombone 6½AL
25.40mm · Deep
14½D
24.50mm · Shallow
5GS (small shank)
25.50mm · Deep
6½AM (small shank)
25.40mm · Deep
Mega Tone Trombone 6½A
25.40mm · Deep
1¼GM
27.50mm · V.Deep
11C
24.70mm · Shallow
15E
24.40mm · Shallow
Mega Tone Trombone 5
25.50mm · Medium
Kelly (17)
12C
24.13mm · Shallow · Lead
6-1/2AL-LS-SS
25.15mm · V.Deep · General
BASS-BONE-LS-SS
27.69mm · — · Bass
SKY-SS
24.64mm · Shallow · Lead
BEAST-LS-SS
28.70mm · — · Bass
JAZZ-LS-SS
25.65mm · — · Jazz
SYMPHONY-LS-SS
25.65mm · — · Orchestral
51D
25.40mm · — · Professional
51D-LS-SS
25.40mm · — · Professional
51D-SS
25.40mm · — · Professional
5G
25.40mm · — · Orchestral
5G-LS
25.40mm · — · Orchestral
6-1/2AL
25.15mm · V.Deep · General
6-1/2AL-SS
25.15mm · V.Deep · General
BASS-BONE
27.69mm · — · Bass
BASS-BONE-LS
27.69mm · — · Bass
51D-LS
25.40mm · — · Professional
Frequently asked questions
Which brand makes better trombone mouthpieces — Bach or Kelly?
Neither brand is universally better. Bach has 74 models and Kelly has 17. The best choice depends on your playing style, preferred cup depth, and tonal goals. Compare specific models head-to-head to find the right fit.
How do Bach and Kelly trombone mouthpieces compare in size?
Bach averages 25.40mm cup diameter with 6.40mm throat. Kelly averages 25.86mm cup diameter with N/Amm throat.