Keith McNicholl, Bass and Contrabass trombone of the Royal Opera House Covent Garden London, approached me, originally, to customise a lovely old Alexander "Cimbasso" model F contrabass trombone. We discussed, back and forth, for a good 2 years, before Keith asked if I could make the bell section shorter, like the Alex Opera model. At this point I suggested it might be a better and cheaper idea to build a new instrument from scratch. And so it started...

Along the way, it was agreed to make the slide interchangeable with Keith's Conn 73H bass trombone slide, this works with an alternate tuning slide, to go with the the shorter bass slide. Because of this, the slide on this instrument uses Conn barrels. This, not only enabled us to swap slides, but makes the contra slide very light and agile. Effectively, a Conn style slide that's long enough for a full seven positions on an F instrument! If it was good enough for the late, great Larry Minick to use Conn parts then I'm in good company!

For me as a maker, one of the big challenges was weight distribution and finding room for nearly 2 meters (6'6") of tubing for the Bb valve. The layout I came up with keeps plenty of weight at the back of the instrument and keeps the wrap close to the centre axis, so the weight doesn't put torque on the players left wrist. So what we end up with is a fairly open wrap that drains to one point with a water key (same for the D valve)

We chose a dual bore slide configuration much smaller than most F Contras. 562 upper and 578 lower. This gives us an almost infinite choice of leadpipes. Currently it has 2 from O'Malley Brass in Chicago. Their 50B Mount Vernon and their Larry Minick pipe. Both in unseamed yellow brass.

The bell section is of 0.7mm/.028" thick Rose brass. The complete rest of it is all Nickel Silver (except the Denis Wedgwood Saturn Water Keys.

My design idea is based on what I do with the Cimbassi I build. The valves are 650 bore. Very large, but balances with the smaller bore slide beautifully, giving the instrument a voice more in keeping with the rest of the trombone section and not a huge gap, as with many contras, between bass and contrabass voices.