PreAmp Gain and Impact on Amp

It has nothing to do with load. If you feel that it's not enough gain(usualy you'd have to use the most of your volume control dial), you can either adjust it if possible or purchase different preamp.

Sufficient gain is as important as fuel delivery from fuel tank to the engine: poor fuel delivery will lack pressure and acceleration while rich fuel delivery will increase fuel consumtion but increase high-speed and high-rpm performance.

You need to 'fill up' the input of your amp with preamp making sure that output voltage with gain set to zero will deliver sufficient voltage for the full power output of your amp.

It's all usually written in specs tested at 1kHz: Output Voltage, Input Sensitivity, etc...

If you have the volume max'd, you don't have enough gain. If the volume control sits near the bottom, you have too much gain. The idea is to have just enough gain for adequate listening levels and a bit extra for that party and your son to blow the speakers. For less than adequate speakers, volume control and distortion control are fairly synonomous.

Some sources have an internal switch to raise output voltage, which is the same as more gain.

You should have full power on average at about 1 o'clock position to leave reserves of gain for soft sources or soft recorded CDs.

Full power is around 4pm on my volume control. The control has 2db increments so maybe I should remove the 6db gain reduction resistor?

4PM seems far but it is OK if you don't have much softer recorded CDs. I have level control jumpers on my Benchmark DAC1 in -10dB increments (0dB, -10dB, -20dB, -30dB). I found that 0dB (loudest) position gives me the best sound (vivid). I normally listen in 10-11 o'clock. Full power is at about 1-2 o'clock. If removing gain reduction resistors gives you better sound and you still have enough resolution when you listen at low volume then why not.