I recently owned Merlin TSM Milleniums. I have not heard the Revel M20s but currently own a pair of F-30s. For me the biggest difference besides limited bass (TSM) is the signature personality that the tweeters possess. The Merlin uses one of the finest soft dome tweeters that I have ever listened to. It gets the midrange right, in fact super right. The metal dome tweeter on the Revel F-30 is distinctly metallic but still eminently listenable. My biggest complaint with my TSMs was the serious lack of a bottom end. I have no regrets overall in moving over to the Revels but to go back to the orignal question the comparison is between 2 speakers that have limited bass and of those 2 I would be attracted to the TSM Midrange enough to go with the Merlins. In the long run I realized that for my listening preferences, I needed a more full range speaker despite the superb micro quality the TSMs were capable of. Not a direct comparison but family characteristics that can be compared somewhat. Hope this helps a little.
Oh yeah, forgot to include the fact that when you buy a pair of Merlins you also get a piece of their designer; Bobby Palkovic. This in itself is worth big bucks because Bobby will become your best friend and expert when you have questions regarding his speakers. He is a musician (so is Bill Hooper his right hand man)and he has been incredibly helpful over the years when I have had system issues. I have owned 3 different pairs of Merlins over the years. I value designers that are also musicians because that brings an entirely different spin to the design process for stereo equipment, Bobby and Bills sensitivities to music become apparent when you listen to their products. Merlin speakers are nothing if they are not musical.
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Oh yeah, forgot to include the fact that when you buy a pair of Merlins you also get a piece of their designer; Bobby Palkovic. This in itself is worth big bucks because Bobby will become your best friend and expert when you have questions regarding his speakers. He is a musician (so is Bill Hooper his right hand man)and he has been incredibly helpful over the years when I have had system issues. I have owned 3 different pairs of Merlins over the years. I value designers that are also musicians because that brings an entirely different spin to the design process for stereo equipment, Bobby and Bills sensitivities to music become apparent when you listen to their products. Merlin speakers are nothing if they are not musical.
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