Critical Mass finally marked a period of stability for the U.K.

progressive metal group Threshold.

For once, the band released a new studio album within two years of the previous one, with the same lineup and on the same label.

How did it translate into the music? By a growth in the group's musical strengths and maybe just a step backward in the writing.

Lead vocalist Mac sounds more assured, if possible, delivering a performance that should inspire others to follow his example.

Ditching overly theatrical clichés, he focuses on staying on the note and keeping a pleasant tone instead of faking emotion by screaming at the top of his lungs.

The rhythm section of Jon Jeary and Johanne James is rock-solid and efficient, if not sometimes a bit too fancy-free.

As for the writing, a few songs sound a little too catchy for their own good, with the seams of the solos and bridge sections showing.

Two noteworthy exceptions are "Echoes of Life," an impressive take on the soft-hard-soft epic, and the closing 14-minute title track (which includes the only acoustic guitar segment of the whole album).

"Phenomenon" and "Fragmentation" are supported by their catchy melodies and crunchy riffs, but they remain rather plain.

On the other hand, "Round and Round" features a very ingenious chorus.

Critical Mass will not rewrite the laws of progressive metal, but it sure caters to the fans.

A limited deluxe edition includes an extra CD single (with two non-album tracks) and multimedia goods.