i am using YBA Passion Integre to drive the Micros. my amp is rated 50W at 8ohms which is not considered as powerful as SS amp but it has no problem driving the Micros. the quality of the amp matters much more because Micros is very revealing. the YBA amp has two kinda output: high damping factor output and low damping output (tube like). the low damping factor output has fuller sound and especailly fuller (or uncontrolled if you wanna call it in this way) bass with a bit loss of transparency and bass extension (as mentioned in YBA manual) but so far i feel it gives much better result for Micros for jazz music. it compensate the lean bass of Micros.
now comes back to the bass issues of Micros. maybe i rephrase my previous statement a little bit. the bass of Micros is OK for a bookshelf speakers. however comparing to the PERFECT tweeter and PERFECT midrange, it's obvious less perfect. but of course that's why there are high range models like Diva/Alto/Grand Utopia. the bass of Micros rolls out quite sharply from around 50hz. however above 50hz, the bass has tons of textures, details, speed, pace, with a warm touch. all i can say is, it does a good job within its limitations (50hz -3db) but not beyond that. i assume anyone who adopt Utopia series has the objective of pursuing perfect sounding without compromise. thus i feel a good subwoofer is still necesary in this sense.
now comes back to the bass issues of Micros. maybe i rephrase my previous statement a little bit. the bass of Micros is OK for a bookshelf speakers. however comparing to the PERFECT tweeter and PERFECT midrange, it's obvious less perfect. but of course that's why there are high range models like Diva/Alto/Grand Utopia. the bass of Micros rolls out quite sharply from around 50hz. however above 50hz, the bass has tons of textures, details, speed, pace, with a warm touch. all i can say is, it does a good job within its limitations (50hz -3db) but not beyond that. i assume anyone who adopt Utopia series has the objective of pursuing perfect sounding without compromise. thus i feel a good subwoofer is still necesary in this sense.