This Bach 42BOF is a Stradivarius model .547" large bore trombone (42) with the Meinlschmidt Open-Flow rotor and new F-attachment wrap (BOF). The hand slide includes interchangeable leadpipes (LP).
The 42BOF has a rotor design and bell bracing similar to a Greenhoe. It has the compact F-wrap from the Artisan model, and Bach borrows the leadpipe fitting from the Conn 88H Gen II. Included leadpipes are Bach standard, open and long open, plus two additional pipes made by Kanstul.
The Open-Flow rotor brings the response of the Bach 42 to another level. The traditional Bach rotor gives some resistance, and this new rotor design lets you breathe more through the instrument and not push as much. It takes a little practice to get into the larger feel, but it's much more captivating.
Over the years we've sold many stock model Bach 42 trombones, and also worked through many, many custom Bach slides for client requests. A few trombones were ordered as components and assembled from available parts in-store. One of the very last 42 trombones here, this 42BOF didn't blow as easily as I liked. Turns out, it was easily fixed with a small wooden brace. Back story: Years ago, a new Shires model trombone had a bell which would ring when you played marcato. The ring was loud and unsettling. Shires figured out that his brace-free 2-point bell mounting system let his bells vibrate like a tuning fork, and some combinations went a bit crazy. He first solved it by fitting a small block of wood dowel between the tuning slide ferrule and the F slide tube. Later production models had a small metal brace that was adjustable for a tight fit.
When I look at a Bach 42B trombone like David Rejano plays, it has four places of connection between the F-attachment and the body of the horn. That bracing adds some rigidity which also means projection, and it's the standard way to build the classic Bach design.
Compare to the 42BO Open Wrap, which has only three points of attachment and also shorter F-slide sleeves. Less rigidity, less weight, making 42B vs. 42BO not just about the shape of the F-attachment loop, but also about the mass and the bracing.
And now this 42BOF. It has zero connection points between the F-attachment and the horn's body. Nothing touches the neckpipe or the bell. The F-loop is attached only from the center of each main brace, far from the air-wave. It's not just the rotor, but the bracing is far different here than on other Bach models. And somehow this particular one didn't project or pop in the high range like I wanted. It reminded me of Greenhoe trombones...
Greenhoe trombones are lightly braced this way and we went through several Greenhoe trombones that just did not play. Dull, no oomph, no gas. So I got out my bag of Shires wood braces and installed some, and those Greenhoes all became spectacular players, just by adding a little more rigidity than the mantra of the makers would allow. Lesson: Bracing is important and very light horns may need a few more. Look at trombones by the Thein brothers: they add small weights all over their horns, ostensibly for the same reason.
After those other successes, this Bach 42BOF was easy. After adding a small piece of dowel behind the tuning slide, it's a new horn. Now it projects, it centers, it wants to play higher even. I know, hard to believe, trust me. This is a nice trombone, and you can choose one of the leadpipes to perfect the relationship between player and instrument.
You can also try this yourself at home and add a small brace to your lightly braced trombone if it doesn't play like you want. You may hit nirvana, and your horn becomes friend rather than foe.
There are other ways to add mass and rigidity to accomplish this, each with their own quirks or expense:
But this Bach now seems to work well as is, it's a nice trombone. The brace adds no weight or expense, just efficiency. The Bach 42OF includes a new Bach hard case which is neither light nor tiny but it's tough and it flies well as checked baggage because it's made to fit the horn exactly. Includes Bach 341 5G mouthpiece or your choice.