Great songs spring from the minds of musicians, but they’re polished into hits in the recording studio. After working at Abbey Road Studios and Olympic Studios, British audio engineer Dick Swettenham went into business for himself in 1969, building recording consoles to order. Audiophiles in the know still speak of his Helios units with reverence. Bonhams offered a unique Helios machine in December with a remarkable history.

Dubbed the HeliosCentric Helios console, it unites two Helios machines. The center comprises parts of both, but the left side consists of the Island Records Basing Street Studio 2 Helios Console, used by Led Zeppelin to record songs for Album IV, including Stairway to Heaven, and by Bob Marley & The Wailers for their albums Burnin’ and Catch a Fire. The right side first belonged to Alvin Lee’s Space Studios, and served the needs of George Harrison, Mick Fleetwood, Ron Wood, and many others.

In 1996, Elvis Costello and Chris Difford of Squeeze retrieved the consoles from storage and combined them into a 38-channel behemoth with the help of Swettenham. Modern users of the HeliosCentric Helios include Sia, Dido, Supergrass, and the Pet Shop Boys. The winning bidder of the analog treasure, who paid the U.S. dollar equivalent of $141,321, must forge ahead without the guidance of Swettenham, who died in 2000. But even if it never yields another legendary song, its owner can still point to the console, decorated in its exquisitely 1970s-era mahogany veneer and leatherette, and say, “See that? Led Zeppelin recorded Stairway to Heaven on that,” and bask in its inherent coolness.

When you look at it, it doesn’t seem like much. It lacks the word “Playboy” and the famous bunny logo, and it’s relatively small, at one and a half inches by four inches. But those who know the Playboy universe know this plate. It greeted visitors to the Chicago Playboy mansion during the 1960s and 1970s with the Latin phrase, “Si Non Oscillas Noli Tintinnare,” which translates to “If You Don’t Swing, Don’t Ring.”

Officials at Julien’s who prepared the sale of Playboy founder Hugh Hefner’s effects estimated the plate at $400 to $600. To their shock and delight, they watched it soar to $51,200, with the saleroom crowd cheering on the bidding after it passed $10,000. Hefner took the sign down after he moved out of the mansion in 1974, and he installed a replica in the Los Angeles Playboy mansion. The Los Angeles sign was in the auction, too, and sold for $1,600 against an estimate of $50 to $100.

Wendell Castle gleefully and deliberately blurred the line between furniture and sculpture for six decades, and carried on innovating until he died in January 2018. The American artist’s fourteen adopted rules of thumb, which appear at the tail of his biography page on the website of the Friedman Benda gallery, which represented him, includes this edict: “If it’s offbeat or surprising, it’s probably useful.” His In God We Trust chair reflects all three of those qualities. Fashioned by Castle in 1964, the unique oak and leather chair features the phrase on its crossbar, inscribed in a suitably sober font.

The chair displays the mastery of a young-ish (he was 32 in 1964) artisan in full command of his powers. It’s a magnificent collection of lines and curves that converge in the peak of the chair’s back, forming a silhouette that calls to mind the famous Dürer drawing of praying hands. And, befitting a man who emphatically embraced change, it looks fresh enough to have been finished last week. Estimated at $60,000 to $80,000, the chair sold for $75,000.