These audio examples accompany Mike Senior's 'Picking Out' Reaper technique article from Sound On Sound May 2012.
Here's an example of an acoustic phrase which, despite the appropriateness of percussive picking noise to the musical style, goes a little bit overboard in this department, especially at 0:12-0:13.
Here's the same audio as you heard in the PickNoiseReduction_ReaXcompOut file, but with Reaper's ReaXcomp applied to smooth off the excessive pick noise. As described in this month's Reaper article, I used a two-band configuration, limiting the higher frequencies at a 100:1 ratio, setting the band's attack and release times to 1ms and 3ms respectively and the RMS size to zero. The band's Threshold was adjusted under automation control.
Another section of guitar recording that features some moments of overbearing fret noise — at 0:01-0:02 in this example file.
The same super-fast high-frequency limiting I used to combat pick noise in the PickNoiseReduction_ReaXcompIn file also has the potential to soften the fret noise heard in FretNoiseReduction_ReaXcompOut. Exactly the same settings were used, with the obvious exception of the high band's Threshold automation.
This audio example demonstrates how soundhole resonance can make a few of the guitar's low notes dominate in the balance, booming out in a way that makes the musical lines feel uneven. In this particular case, it's the low G and F# notes you need to listen for at 0:03, 0:06-0:07, 0:13, 0:17-0:18, 0:22-0:23, and 0:28-0:39. (To listen to the final mix of this piece, check out the track 'Sea Shapes' from the David Youngs album 'Transience' — www.davidyoungs.net.)
Reaper's ReaXcomp provides one means of dealing with low resonances such as those you can hear in the BoomReduction_ReaXcompOut file. In this audio example I've set it up along the lines described in the article, processing only the low-frequency region. The ratio is set at 8:1, with attack and release times at 6ms and 45ms and the Threshold parameter under automation control. I also refined the crossover point between the bands after some critical listening (again as suggested in the text), raising it to 213Hz so that it reined in the unwanted 'boom' a bit more effectively.
This compressed, chordal guitar part features one of the imbalanced midrange harmonics mentioned in the main article — a ringing high 'D' at 1188Hz that ducks in and out of the guitar texture throughout this excerpt, becoming particularly loud from around 0:08.
A single band of peaking cut from Reaper's ReaEQ was able to straighten out the imbalanced 1188Hz harmonic you heard in HarmonicZapping_ReaEQOut, even though its bandwidth was only set to 0.07 of an octave. The gain of the band was automated so that it was only applying as much cut as required from moment to moment. You can still hear the harmonic in the mix, but it's much more in keeping with the rest of the sound.