Entertainment editor Jon Niccum

In the 1980s, a tape surfaced that featured Linda McCartney singing with husband Paul in the band Wings.

Paul had decided to add his wife to the touring lineup of his popular post-Beatles project, subsequently teaching her how to play keyboards and sing backing vocals.

The tape was culled from a board mix of a concert version of “Hey Jude” in which the engineer had decided to isolate Linda’s vocals. The motive was because they were so excruciatingly bad.

Inconsistent, out of tune, constantly changing register to suit a limited range – her vocals were like listening to a performance art piece parodying the classic Beatles anthem. The results were unintentionally hilarious.

(The complete audio of this and other recordings cited in this article can be found here.)

This tape became less funny when humanitarian Linda died of breast cancer in 1998. Afterward people tended to forgive and forget this sidebar of her admirable career.

However, a new crop of isolated vocal tracks are available on the Web.

Want to hear how the more musically gifted of the McCartney clan fared? Then check out the studio version of “Sgt. Pepper’s Lonely Hearts Club Band.” Since recording techniques were more limited in the 1960s, the lead and background vocals are performed together with no overdubs. One can hear Beatles members snapping their fingers to keep time within the reverb-heavy recording.

The nakedness of the cut only magnifies how stellar the performances remain.

But the piece de resistance in this solo vocal frenzy hails from Van Halen. The band’s 1978 eponymous debut album opens with the radio staple “Runnin’ with the Devil.” Now the lead track featuring flamboyant singer David Lee Roth is available by its lonesome.

Considering the song isn’t exactly brimming with melody, Roth fills the tape with an endless stream of yeahs, woos, grunts, profanities and primal screams. It’s the sonic equivalent of Tourette’s syndrome.

Always entertaining are “Diamond” Dave’s “ease the seat back”-style ad libs. No one is more comfortable taking first-person lyrics and throwing in second-person impromptus. (“Baby, you know I ain’t lyin’ to ya!”)

Yet on the few occasions when Roth actually “sings,” he’s pretty good. “Devil” is a tad out of his husky range, but he manages to climb for the notes.

Here’s hoping Roth survives so the joke never gets old.