Vincent Bach – Trumpet Bell Variations
Bell Construction – Bending
Selmer around 1973 changed the filler material in the bell crook to a frozen soap type filler from the previously used, confidential alloy of pitch type materials that had been developed through the 1950-1960’s.
Bell Construction – Blank
Instead of the traditional funnel shape or fan pattern after 1965 the Selmer Corp. used a newly developed flower “blank” shape that simplified the forming process and required a completely different approach to shaping the bell flair. Photos of the manufacturing process can be found here.
Bell Construction – Bracing
Early Bach trumpets used cast braces to attach the bell to the lead pipe, valve block. Today forged S braces are used instead.
Bell Construction – Logo
Similar to the valve serial number engraving, bells today are etched, where earlier Bach trumpets were roll stamped to get the logo applied. This was switched over around 2000/2002 to a computerized laser based system.
|Serial Number||Bell Model||Logo Method||Approx. Year|
Bell Construction – Logo registered Trademark
After some helpful comments from fellow Bach loyalists (David, Tim), wanted to add some examples in this section. It is unclear when both the registered trademark, and the Corporation was added/removed from the Bach brass related bells. Here is a table which summarizes different examples.
It is important to note the major events during this same time. For example, Vincent Bach Corp. was sold to Selmer in 1961, and was part of the Selmer Musical Instrument company. (That would have been around serial number 21,000.
Another way to look at this is by the bell type. Perhaps the differences were related to the fixturing for stamping the logo on different bell mandrels. Same list as above, but sorted by bell type.
37 Type Bell
43 Type Bell
Bell Construction – Indiana, USA
Similar to the registered trademark/corporation above, there are variations to the State marking from IND. to IN, and also from U.S.A. to USA.
|412786||IND.||U.S.A.||Vertical Serial Numbers
|IN||USA||Bell Font Changed
Vertical Serial Numbers
Please send us your notes on what serial number this changed also on your Bach brass instrument. Help us narrow down the serial number range.
Bell Construction – Model 182
in the U.S.A”
* Please note the serial numbers for the model 182 do NOT follow the traditional BACH Stradivarius serial number list.
Bell Construction – Rim
The Elkhart bells (>1965) have full round bell wire, versus early Bach trumpets which had a more traditional French half round bead.
Bell Construction – Seam
Early Elkhart, Mt. Vernon bells have the seam running towards the valve section.
Bell Seam Example 
Serial Number 48765
There have been different variations through the serial numbers. Some other examples include
(looking into the bell).
|Serial Number||Seam Position|
|117XX (NY 37ML)||6 o’clock|
|188XX (MtV M Bore)||7 o’clock|
 Thanks to Chris Kase for these additional examples.
Bell Construction – Thickness
On older Bach trumpets the bell thickness is tapered as the bell flares out. Today, through modern manufacturing techniques, the bell thickness is much more uniform, allowing for similar sound vs. daily manufacturing variations. This is one reason why older Bach trumpets often have a different sound to them.