100 watts enough?

@tarheelneil51,
The listening distance (4 meters) factor was accounted for in kijanki’s calculations. See his post above.


’Based upon the information supplied by the OP, I would go with quality over quantity.’, Per @onhwy61.

Yep, this is my point. A very (Perhaps ultra) high quality solid state amplifier driving speakers that for the most part have a speaker impedance of 10 ohm or above. Dip no lower than 4 ohm in the lower bass. This is not a challenging load for the very robust designed CH Precision A1 amplifier (Substantial power supply and capacitance reserve). Quality indeed. 
Charles

@unsound I hear you. I’m just basing it the OP suggesting his listening levels are modest. "I don’t ever crank it up". OP hasn’t chimed in to say what exactly those listening levels are in db for a better understanding. Modest levels to me would be mid 60s to mid 70s db C-weighted. In which case he’d be using only small fractions of a single watt.  10 watts gets him 92 db SPL. Well an interesting topic nonetheless. @unsound I appreciate your thoughts.
Charles

@unsound,
Not petty. However given what we know,  kijankii’s calculations and Stereophile measurement/testing, why would one conclude "merely adequate "?
Charles

Hi @tomic601,
I bet Casa Pacifica sounds absolutely gorgeous!
Based on Atkinson’s description of the  Eggleston Andra speaker impedance characteristics I believe that your  Music Reference RM-9 would a good match.
Charles

From John Atkinson/Stereophile,

"The EgglestonWorks Andra is moderately sensitive, my estimated 87dB/2.83V/m (B-weighted) reading agreeing with the specified figure. Its impedance plot (fig.1) suggests that the speaker appears to be an easy load for an amplifier to drive, the magnitude dropping below 10 ohms only in the high treble and below 130Hz, and the phase angle generally remaining low. However, it does reach 4 ohms in the low bass, around the tuning of the twin ports. There is a very slight wrinkle in the impedance traces between 300 and 400Hz, this generally indicative of a cabinet resonance of some kind. However, as might be expected from its massively constructed cabinet, the Andra is impressively inert. About the only resonant mode I could find was on the woofer enclosure wall (fig.2) at 350Hz. This is well down in level, however."

Given this assessment coupled with the OP's stated  "neighbors"  situation it seems that the CH Precision 100 watt amplifier is far more than adequate . I guess I'm missing the rationale of why a more powerful amplifier is advantageous.  It appears that this amplifier would coast driving the  "easy load"  (Atkinson's words) Andras to suit the OP's circumstances. 
Charles 

Hi @unsound,
I get your point about loud volume levels and certainly it is subjective amongst respective listeners and their perception of such. Given the OP’s stated condo listening limitations/situation I’m guessing (And could be wrong) that 92 db SPL would be pretty loud relatively speaking.
Charles

@unsound wrote,
’Many amp designers suggest that amplifiers are typically at their most linear when operating at about 20% of their output and further suggest having about 80% headroom.’
This seems very logical. 20% = 20 watts from the CH Precision amplifier.

Kijanki calculated based on robal’s seating distance from his speakers (Accurately in my opinion) 1 watt will provide 82 db SPL and 10 watts will provide 92 db SPL So definitely not exceeding the range of desired amplifier output linearity. 92 db is loud (Assuming no hearing deficits) and probably well above robal’s listening levels in his condo environment (Achieved with only 10 watts).

CH Precision amplifier is providing 100 watts of very high quality.
I don’t see the rationale for recommending higher power amplifiers for robal’s stated needs and circumstances. His speakers are 6 ohm impedance (Minimal) so they are not demanding of high current capability amplifiers. 
Charles