John Doyle is — to my ear — about the best rhythm player in roots music today.  Ever since first hearing him as the original guitarist with the Irish super-band Solas, I’ve been taken with the mixture of power and musicianship in his playing. In recent years, Doyle has been playing in a duo with Fiddler Liz Carroll, and they just released a new CD in March on Compass Records.   As promised last week, I’m highlighting several new releases from Compass in the hopes of encouraging others to take a look at this label’s varied offerings from a talented group of artists. Double Play is the second release from the Carroll/Doyle duo.  The CD begins with a medley of two Carroll tunes, The Chandelier and Anne Lacey’s.  Liz Carroll is not content to simply play traditional tunes, but she’s quite a composer of new Irish music.  The interplay between the major key of The Chandelier and the minor tones of Anne Lacey’s makes for a great pairing. Doyle’s singing is strong on tunes such as …