See a description at The Horn Guys web site.

The Ferguson 2 is a bit of an odd design. It's unusually deep and open for a mouthpiece in that size range. Personally, I couldn't make it work on tenor, it was just too deep a cup and too open a throat for me and gave me a dull sound with weird intonation on my 42 (although I'm sure it would work great for some people), took more air to get a decent sound, and I found it very tiring to play (more even than playing on a larger rim size than I usually did). But I later found that for me it was an absolutely fabulous mouthpiece to use on bass when I wanted a lighter and compact sound on repertoire that doesn't need the weight or low register of a normal big set-up, for example classical rep with alto, especially when 2nd stayed on large bore, repertoire written for three tenors, or light repertoire with only one trombone playing a bass part (Chopin piano concertos, for example).

It's deep and open enough to work in a bass and not sound mismatched to the horn (I suspect the extra weight probably also contributed to making it work).

For doublers who use something in the 6.5AL–5G range on tenor, this is something worth trying.

I have used a Ferguson 2 on my Holton 156 and 159 (.547".559" slide/.562" bell section) with good results.

I’m selling a Ferguson 2 in good condition if anyone is looking!

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