Dick Olsher has posted a review of the Atma-Sphere S-30 MK 3.3 OTL power amplifier ($4300) at The Absolute Sound. His conclusions:
“Although the S-30 is guilty of slight timbre alterations, and presents a somewhat dark tonal balance, these acts of commission, most likely due to load interactions, did not generally interfere with the music, but point out the need to mate the amp with a compatible loudspeaker and front-end electronics.”
You can read the full review here.
