Struggling with nested IF formula

Hi

I posted here on Tuesday, but have been away. Thought it better to post again.

I am writing a calculation sheet which simply compares values:

* If the difference between L2 and B2 is >=10, then the value is L2.
* If the difference between L2 and B2 is >=6 AND <10, then the value is the logarithmic equation
* If the difference between L2 and B2 is <6, then there is a simple subtraction of 1.3 from L2

Here's the formula I am using: =IF(L2-B2>=10,L2,IF(L2-B2<6,L2-1.3,IF(AND(L2-B2>6,L2-B2<10),10*LOG((10^(L2/10))-(10^(B2/10))))))

When I use real data, the above corrections do not seem to work. So, I am sure I have done something fundamentally wrong. I'm just not experienced enough to figure it out. Can any of you experts help?

Many thanks, for what must seem ultra-trivial.

Raz