(iii) One solution ; find an online Lpad calculator / and use it to calculate the resistor values for a simple fixed 8 ohm Lpad that's set to attenuate anywhere from 3 to 6 db . I'd try 3 db of extra padding first to see if that returns enough play ( in the variable Lpads ) .
- Once you have the values build this fixed ( two resistor type ) Lpad into the circuit just before the driver ( after R6 ). At this point you'll notice that you have two inline resistors connected to each other ( R6 & Rwhatever). Blend the two into one ( add the values directly ) and replace the two resistors with the single blended value ..