increase power amp sensitivity

Hi and thanks for reading this post.

I have 2 power amps driving a pair of speakers via an active crossover.

The first amp drives the bass mid unit, the second amp drives the tweeters.

What i am finding is there is not enough treble on the music, probably because of the amp design, the sensitivity of both amps is different leading to one amp sounding louder than the other.

I have been fiddling around with it for the past few days and perhaps have come up with a solution. I want to raise the sensitivity of the amp driving the tweeters, there is a 200k ohm resistor across the phono input (screened cable input) of the amp driving the tweeters:

1. What if i were to remove this resistor all together?

2. there is a 20k ohm resistor and 500 nano farad capacitor in series with the phono input, which then goes to the op-amp, what if i were to reduce this resistor by 50 percent. Would i have to change the capacitor value as well.

3. The input impedance of the power amp needs to be high, but i read about impedance matching where i can match up the output impedance of the pre amp with the input impedance of the power amp and get good results. The output impedance of the pre amp is 100 ohms, so would it be okay to replace the 20k ohm resistor with one of 100 ohms value.

Many thanks.