You might expect the first studio leak from this group of well-established indie rockers to be one part aggro-daydream (Helium frontwoman Mary Timony) to two parts rocket thrust (Sleater-Kinney's Carrie Brownstein and Janet Weiss) with a taste of garage-pop sugar (the Minders' keyboardist Rebecca Cole). Actually, "Glass Tambourine" — half of a seven-inch vinyl single due out on Record Store Day, April 16th — sounds like some wicked 1960s acid-rock yard-sale discovery, with Timony urging, "Listen to the music . . . before it passes you by." Then, Wild Flag launch into a ferocious closing guitar jam that's two parts Stooges, one part early Pink Floyd. Psych!

Listen to "Glass Tambourine":

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“Is It True”

As the British Invasion reached its peak in 1964, Brenda Lee went from Nashville to London to record one of her hardest-rocking hits, her perky vocal backed by a stuttering, squalling guitar. That guitar was played by session musician Jimmy Page, yet to skyrocket to fame with first the Yardbirds and then Led Zeppelin. "She said to me, 'I've come here to make a record with the British sound,'" remembered producer Mickie Most. "She felt she wouldn't get the same sound in Nashville because they're only just catching up on the British beat group sound of about six months ago."