Calculate ratio and DX7 matrix

Hi
i started to learn FM synthesis since few days, and i have 2 questions please :

I want to know how to calculate the ratio when he is not integers : example (ramdom) : op 1 : 0.6845 op 2 : 1.3255
someone can explains me what this parameters does with the offset ? i have readed manual but it's not understood for me ...

2nd problem, i am not able to distinguish the factory algorithm od the DX7 and the factory algorithm
of native instrument's FM 8.

Thank you

 

These links should be helpful:

• http://www.adsrsounds.com/fm8-tutorials/understanding-fm8-ratios-and-pitch-offset-parameters/
  
• www.youtube.com/watch?v=1d2fY5q8yOE

What exactly do you mean with 'distinguish the factory algorithm'?
Can you please give more details which algorithms, patches, etc. you are trying to compare ...

 

wow ! thank you for the link i have found the answer.