Today I thought what is the 7th chord in the key of C on B that is and I get so confused,,first I thought it was a minor chord but that could'nt be 'cos of the F# note in it and F# is'nt in the scale,,than I thought is it a B ,,well no way,,also an F# in it.. the wheels in my head said it must be something with an F but B with an F,,i could'nt get it,,SO I searched what it must be in the genius lesson and now well I think I never forget it again,,it must be a DIMINISHED chord B-D-F.. It was a great lesson on triads.. it costed me a little hour to get it but now never forget it...
willem