Please I need help to calculate resistance?

[FriedMule]

If you should find the most neutral way to adjust the volume and balance, what technique / component would you take a look at?

[Ian.M]

First define 'neutral'!  If you are looking for an audiophile grade solution, I'd consider a pair of R-2R multiplying DACs built from gold plated contact reed relays and precision non-inductive resistors, controlled by a MCU that returns to a clock stopped deep sleep mode (to avoid it contributing any digital noise) once it has made any attenuation change until it is woken up again by further user input.  For audiophools,ditch the MCU and control the relays from pair of concentric rotary switches  via a diode matrix that 'programs' the attenuation steps.  For the rest of us, the best digitally controlled volume/balance chip we can afford is probably a better choice!

[FriedMule]

LOL sounds interesting, but it sounds to me like you didn't write English in 90% of the text:-)
Or in short, have no idea on what it means:-)

EDIT: my original idea was also to separate the control unit from the audio, so I could use cheap standard parts while only a single component did touch the sound.