if the Denon in question is actually the AVR X1100w then here is the specs from web manual-
o Audio section
0 Power amplifier Rated output:
Front:
80 W + 80 W (8 Ω/ohms, 20 Hz – 20 kHz with 0.08 % T.H.D.)
120 W + 120 W (6 Ω/ohms, 1 kHz with 0.7 % T.H.D.)
Center:
80 W (8 Ω/ohms, 20 Hz – 20 kHz with 0.08 % T.H.D.)
120 W (6 Ω/ohms, 1 kHz with 0.7 % T.H.D.)
Surround:
80 W + 80 W (8 Ω/ohms, 20 Hz – 20 kHz with 0.08 % T.H.D.)
120 W + 120 W (6 Ω/ohms, 1 kHz with 0.7 % T.H.D.)
Surround back:
80 W + 80 W (8 Ω/ohms, 20 Hz – 20 kHz with 0.08 % T.H.D.)
120 W + 120 W (6 Ω/ohms, 1 kHz with 0.7 % T.H.D.)
Output connectors: 4 – 16 Ω/ohms
Thiel CS1.2
https://www.stereophile.com/content/thiel-cs12-loudspeaker-measurements
Link from Stereophile review measurements show what looks to be a fairly balanced impedance load. If the Denon is not asked to play in excess it would appear that it would and could work at reasonable SPL. Problems arise quickly when clipping of the amp is introduced, ie- blown tweeters usually happen first. Again, given a safe dynamic range to work within the Denon looks like it will work, just not up to the optimal level the Thiels would prefer or shine in.
o Audio section
0 Power amplifier Rated output:
Front:
80 W + 80 W (8 Ω/ohms, 20 Hz – 20 kHz with 0.08 % T.H.D.)
120 W + 120 W (6 Ω/ohms, 1 kHz with 0.7 % T.H.D.)
Center:
80 W (8 Ω/ohms, 20 Hz – 20 kHz with 0.08 % T.H.D.)
120 W (6 Ω/ohms, 1 kHz with 0.7 % T.H.D.)
Surround:
80 W + 80 W (8 Ω/ohms, 20 Hz – 20 kHz with 0.08 % T.H.D.)
120 W + 120 W (6 Ω/ohms, 1 kHz with 0.7 % T.H.D.)
Surround back:
80 W + 80 W (8 Ω/ohms, 20 Hz – 20 kHz with 0.08 % T.H.D.)
120 W + 120 W (6 Ω/ohms, 1 kHz with 0.7 % T.H.D.)
Output connectors: 4 – 16 Ω/ohms
Thiel CS1.2
https://www.stereophile.com/content/thiel-cs12-loudspeaker-measurements
Link from Stereophile review measurements show what looks to be a fairly balanced impedance load. If the Denon is not asked to play in excess it would appear that it would and could work at reasonable SPL. Problems arise quickly when clipping of the amp is introduced, ie- blown tweeters usually happen first. Again, given a safe dynamic range to work within the Denon looks like it will work, just not up to the optimal level the Thiels would prefer or shine in.