WTC1 C-minor fugue - articulation??

[flaxys112]

Hello, fellow pianists

I've come to realise that I am a quite alot worse pianist, than i thought. I'm selftaught, and untill recently I thought being able to play pieces was a great part of playing the classical piano. But after an audition at which i got some aweful grades, I realised how much articulation and legato etc. means.
   Because I didn't know this before, I've played pieces which are probably way above my level (Chopin Nocturnes etc.).

Anyway - I've been playing the C-minor fugue from WTC1 (BWV 847) and I've always thought that making the theme stand out clearly whenever it appeared was the most important part of playing a fugue. But I got some really bad criticism about it at the audition I went to.

So how do you really articulate in a fugue? I find it very difficult to play it "mechanically" enough to make all the voices come out clearly.

A more concrete question is; in the fugue (ex. bar 10) whenever I end a scale run and I have to start another one, there's like an 1½ octave jump. I CAN'T make this jump come out nice - it always sound all bumpy with a huge change in sound level et cetera... How do I do this? Or how do I at least practice it?

Thanks !