Many, many summers ago, I used to mow my folks' lawn with a Walkman cassette player strapped around my head. Three tapes kept my mid-teen limbs moving briskly through what felt like absolute drudgery back then: the self-titled MONTROSE album, VAN HALEN's "5150" and DEEP PURPLE's "Machine Head". In retrospect, I find a strange symbiosis in this anecdote considering Sammy Hagar filled my ears in MONTROSE and VAN HALEN back then while these days he fronts CHICKENFOOT, who appears on a tribute album to "Machine Head". Maybe you get my wonderment at this synergy or maybe you don't. All I know is the rock gods act in benevolent ways, praise be to them.

While I would much rather see DEEP PURPLE's "In Rock" given tribute from their contemporaries and descendants just to see who has the mettle to take on some of the loudest and heaviest music ever conceived, there's no question why "Machine Head" deserves a ten song salute. The album is iconic. "Smoke On the Water" is a foundation block of rock and metal, as is "Space Truckin'" and "Highway Star". These three songs embody a common language of lexicon between heavy music mongers, as much as BLACK SABBATH's "War Pigs" and IRON BUTTERFLY's "In-A-Gadda-Da-Vida".

"Re-Machined: A Tribute to Deep Purple's Machine Head" on the surface unfurls one hell of a guest list. METALLICA, IRON MAIDEN, CHICKENFOOT, SANTANA, BLACK LABEL SOCIETY and THE FLAMING LIPS are some of the major players on tap here. In a classy gesture of solidarity, MKIII- and MKIV-era DEEP PURPLE bassist/vocalist Glenn Hughes gets a deuce to kick up a storm with. RED HOT CHILI PEPPERS and CHICKENFOOT drummer Chad Smith lends Hughes a hand, as does Steve Vai. Then there's a fledgling supergroup reportedly born for the occasion: KINGS OF CHAOS, which consists of Joe Elliott, Steve Stevens, Matt Sorum and Duff McKagan.

This project in honor of "Machine Head"'s fortieth anniversary purports "re-interpretations", albeit there are only a few moments that could be actually quantified as a true "re-interpretation". By and large the groups called into action for "Re-Machined" play things straight and as a result, this tribute album sparkles at times but merely settles as a whole.

The finest moments on "Re-Machined" belong to Glenn Hughes, which is fitting when you consider DEEP PURPLE beyond the halcyon MKII period has been criminally brushed away from the minds of many. Hughes' take on "Maybe I'm a Leo" is spot-on and it carries an extra jive courtesy of his funky bass work and grooving vocals. On the flipside, his scorching version of "Highway Star" is a pure shot of adrenaline. Steve Vai's ripped-up soloing dusts Joe Satriani and CHICKENFOOT's live version of "Highway Star" appearing earlier on the album. By comparison, CHICKENFOOT's rendition rings conservative, though "Highway Star" has been an obligatory part of their live itinerary it's no surprise they appear on "Re-Machined". Yet Hughes goes right to the edge with his "Highway Star" and it becomes the album's moment of climax, even as a closing bonus track.

Perhaps the biggest surprise of "Re-Machined" is METALLICA's "When a Blind Man Cries". The song doesn't appear on "Machine Head", of course, but it comes straight out of the same recording sessions and kudos to them, METALLICA makes the moment count. James Hetfield might have turned in the vocal performance of his career on "When a Blind Man Cries", a somber ode that only escalates into layers of intensity incrementally. You question for a long time into the song whether that smooth, non-rock crooning is actually Hetfield, but hell if isn't. There's a full-on appreciation for DEEP PURPLE that METALLICA shares with their listeners on "When a Blind Man Cries" it supersedes wherever you might stand with them. You almost want to forgive them for "Lulu". Almost.

The biggest moment of weird on "Re-Machined" goes to, you guessed it, THE FLAMING LIPS, who bring the BUTTHOLE SURFERS' Gibby Haynes along for a hilarious strip-down of "Smoke On the Water". In direct contrast to SANTANA and Jacoby Shaddix's mostly straightforward, calypso-spiced take, THE FLAMING LIPS do to "Smoke On the Water" what DEVO did to THE ROLLING STONES' "Satisfaction". THE FLAMING LIPS tweak the main organ and guitar riffs to sound like actual fire alarm pleats with a nutty sense of minimalism that includes Haynes reciting the lyrics in deadpan moodiness instead of actually singing them. While rock purists will probably cry foul against THE FLAMING LIPS, their moxy is well-met and "Re-Machined" benefits from their tongue-in-cheek discernment.

The other moments of goodness come from the tag team of Jimmy Barnes and Joe Bonamassa who throw themselves a joyous freestyle blues party on "Lazy", while IRON MAIDEN goes bonkers themselves with a giddy hike of "Space Truckin'". Bruce Dickinson states that DEEP PURPLE was his wake-up music as a kid and for sure, he sounds every bit of that kid here. For a band of IRON MAIDEN's rich talents, they opt to pump their cover at a full throb instead of decorate and interchange rhythms as the original did. At the bare bones, it does kick some serious ass. It's MAIDEN, so come on.

BLACK LABEL SOCIETY does an admirable job with "Pictures of Home" while the KINGS OF CHAOS conglomerate dials into a pop-friendly furrow on the already catchy "Never Before". Neither covers are superlative, but like PAPA ROACH's Jacoby Shaddix pleating cleanly alongside Carlos Santana, there's a strange oddity to it all that draws you in, even if the final payouts are merely breakeven.

"Machine Head" did and didn't need this tribute. Only Glenn Hughes and the Barnes/Bonamassa duo replicate the piston-popping spark of Ian Gillan, Jon Lord, Ritchie Blackmore, Ian Paice and Roger Glover. When sampling "Re-Machined" and "Machine Head" in succession, the biggest message the former conveys is how influential DEEP PURPLE has been upon the rock scene. The latter is proof positive. If you haven't learned that Ian Paice is one of the most underrated skin smashers in history, then you're invited to go beyond "Machine Head" and get schooled. Not a drummer on "Re-Machined" matches the intensity level of the fill-happy Paice, but this is all homage. We should take comfort the inspiration shines above the inspired.

DEEP PURPLE went down to Montreux in late 1971 for a recharge and came out of the ashes smoldering before them with a classic in the making. The legend behind "Smoke On the Water" is rudimentary knowledge, but you had to have been a part of the experience or at least within its proximity to truly recapture the agitated essence of "Machine Head". Perhaps that's the fundamental reason "Re-Machined" is only good and not great.