A C7 Chord means a normal chord + a seventh degree to the root, which is actually:
On the white keys of a keyboard the 'seventh' from C is visually a B, thats +11 semis.Code:0+4+3+(10)
But for some reason a C7 chord has a fourth degree of Bb, thats only +10 semis.
Is this only true for the C chord, or why is that?
Why is the seventh degree of a C7 chord a B-flat and not a B?
I really have a very hard time to integrate that.
Please give me the most simple, illuminating answer!