This album has an interesting history. According to Zappa, the material on it was supposed to be part of a four-disc set called Läther, which was split into individual albums when Warner Brothers refused to release it in its original format, fearing lack of sales due to the high price of a quadruple-album. This may or may not be true, as when Läther finally was released after Frank's death, it didn't exactly match the four discs that supposedly came from it (Zappa in New York, Studio Tan, Sleep Dirt and Orchestral Favorites). But regardless of how the album came about, Sleep Dirt remains one of Zappa's better works.
The original vinyl release was entirely instrumental, with styles ranging from the howling feedback of "Filthy Habits" to the lounge jazz of "Flam Bay" to the pomp of "Regyptian Strut" to the mellow acoustic guitars of the title track to the lengthy avant power trio of "Ocean". With the first CD reissue, Zappa added a female vocalist to three tracks ("Flam Bay", "Spider of Destiny" and "Time is Money") who sings lyrics taken from Frank's unrealized sci-fi opera Hunchentoot. Fans have been griping ever since about the lost instrumentals, but the release of Läther made them available again (although in shorter versions).
All in all, this disc (along with the related albums) are prime Zappa and are definitely worth picking up. Or you could just buy the three-CD release of Läther, but if you do you may end up going back and buying the individual albums anyway. Why? Läther doesn't include the song "Sleep Dirt", which gives a rare view of Zappa's mellower side, and the version of "Ocean" on this CD is five minutes longer than the one on Läther. In New York and Orchestral Favorites also include extra material not found on Läther. Ah, hell with it, just buy 'em all.
In my youthful Zappa explorations, I became increasingly wary of later releases, and glossed this one over, among a few others. A few years ago, I read a review of this slab, which touted it as holding true to some of Zappa's greatest instrumental work. Since I don't remember where I read that, I'll repeat it here for others who were unaware:
This is a great Zappa album.
As became the norm for his late '70s work, Zappa compiled this album from recordings of various line-ups, set to tape over the course of years; in this case 1974-76. If you find the vocals in Zappa's work often annoying and obtrusive, you won't be surprised by Harris' work here. Her voice and style are right in line with Frank's and Ray's and Ike's, although a tad less goofy. The four tracks featuring her vocals aren't completely forgettable, and are certainly not out of place. Sometimes operatic, sometimes loungey, she provides some of the best vocals ever set to Zappa's work. However, the true gems here are the first and last tracks.
"Filthy Habits" teams Zappa and Bozzio with Dave Parlato on bass. Parlato comes in with a dark and haunting bass line, which shifts key and cadence occasionally, but is basically repeated throughout the song. As the other half of the rhythm section, Bozzio is given carte blanche by this repetition to go absolutely ape-shit on drums. And he does. Over all that, Frank sets up some keyboards for filler and then goes to town with multiple guitar tracks. He combines a Hot Rats like style with some distorted feedback, and pollutes the bass line with astounding grace. This easily could've been on one of the Guitar comps.
"The Ocean is the Ultimate Solution" is also driven by Bozzio's drums, but Patrick O'Hearn is brought in to add an explosive dynamic to the bass. These three present an instrumental orgy with sonic climaxes happening all over the place, leaving you to either clean up or sleep in the wet spot afterward. Bozzio shuffles along, conducting percussive experiments with bonus snare work and a flashy kick drum pattern in 5/8 that resolves the chaos from time to time. For the first half of the song, Frank's comping and strumming only ceases momentarily to let O'Hearn bust out some super fancy bass riffage. The liners only credit him with bass, but it sounds like an acoustic double bass and brings Mingus to mind. After O'Hearn's explosions, Zappa gains a partner in another double guitar track, and adds an extensive solo throughout the second half of the song. With a few changes in pace and energy, this song ebbs and flows all the way to the disc's delta, where it quietly fades out, leaving resonance in your head and your hand reaching toward the play button to repeat the whole thing again.
I may be biased toward his instrumental compositions, but I wouldn't hesitate to call these two of my favorite Zappa songs ever.
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