Roger,

Against my better judgement, I'll bite: okay, what WAS the one that Jimmy Durante found?

Richard,

I'm not sure what makes a diminished 7th chord a diminished 7th. I was hoping another more enlightened individual would have jumped in here by now to edify us all. The "7th" of a chord is made by lowering the "root" (e.g. the "root" of a C chord is C) one whole step (two frets on a guitar). For the chord of D# that would mean lowering D# to C# to get the 7th. Now to diminish the 7th.....there's the rub. Possibly lower the 7th another half step (one fret)???? I don't know.