Jimi Hen­drix arrived on the Lon­don scene like a ton of bricks in 1966, smash­ing every British blues gui­tarist to pieces the instant they saw him play. As vocal­ist Ter­ry Reid tells it, when Hen­drix played his first show­case at the Bag O’Nails, arranged by Ani­mals’ bassist Chas Chan­dler, “there were gui­tar play­ers weep­ing. They had to mop the floor up. He was pil­ing it on, solo after solo. I could see everyone’s fill­ings falling out. When he fin­ished, it was silence. Nobody knew what to do. Every­body was dumb­struck, com­plete­ly in shock.”

He only exag­ger­ates a lit­tle, by all accounts, and when Reid says “every­body,” he means every­body: Kei­th Richards, Mick Jag­ger, Bri­an Jones, Jeff Beck, Paul McCart­ney, The Who, Eric Bur­don, John May­all, and maybe Jim­my Page, though he denies it. May­all recalls, “the buzz was out before Jimi had even been seen here, so peo­ple were antic­i­pat­ing his per­for­mance, and he more than lived up to what we were expect­ing.” In fact, even before this leg­endary event sent near­ly every star clas­sic rock gui­tarist back to the wood­shed, Jimi had arrived unan­nounced at the Regent Street Poly­tech­nic, and asked to sit in and jam with Cream, where he pro­ceed­ed to dethrone the reign­ing British gui­tar god, Eric Clap­ton.

Nobody knew who he was, but “in those days any­body could get up with any­body,” Clap­ton says in a recent inter­view, “if you were con­vinc­ing enough that you could play. He got up and blew everyone’s mind.” As Hen­drix biog­ra­ph­er Charles Cross tells it, “no one had ever asked to jam” with Cream before. “Most would have been too intim­i­dat­ed by their rep­u­ta­tion as the best band in Britain.” To hear the sto­ry as it’s told in the clip above from the BBC doc­u­men­tary Sev­en Ages of Rock, no one else would have ever dared to get onstage with Eric Clap­ton. Clap­ton, as the famed graf­fi­ti in Lon­don announced, was God. “It was a very brave per­son who would do that,” says Jack Bruce.

Actu­al­ly, it was Chan­dler who asked the band, and who also tried to pre­pare Clap­ton. Jimi got onstage, plugged into Bruce’s bass amp, and played a ver­sion of Howl­in’ Wolf’s “Killin’ Floor.” Every­one was “com­plete­ly gob­s­macked,” Clap­ton writes in his auto­bi­og­ra­phy. “I remem­ber think­ing that here was a force to be reck­oned with. It scared me, because he was clear­ly going to be a huge star, and just as we are find­ing our own speed, here was the real thing.” Fear, envy, awe… all rea­son­able emo­tions when stand­ing next to Jimi Hen­drix as he tears through “Killin’ Floor” three times faster than any­one else played it (as you can see him play it in Stock­holm above)—while doing the splits, lying on the floor, play­ing with his teeth and behind his head…

“It was amaz­ing,” writes Clap­ton, “and it was musi­cal­ly great, too, not just pyrotech­nics.” There’s no telling how Jimi might have remem­bered the event had he lived to write his mem­oirs, but he would have been pret­ty mod­est, as was his way. No one else who saw him felt any need to hold back. “It must have been dif­fi­cult for Eric to han­dle,” says Bruce, “because [Eric] was ‘God,’” and this unknown per­son comes along, and burns.” He puts it slight­ly dif­fer­ent­ly at the top: “Eric was a gui­tar play­er. Jimi was some sort of force of nature.”

Rock jour­nal­ist Kei­th Altham has yet a third account, as Ed Vul­liamy writes at The Guardian. He remem­bers “Chan­dler going back­stage after Clap­ton left in the mid­dle of the song ‘which he had yet to mas­ter him­self’; Clap­ton was furi­ous­ly puff­ing on a cig­a­rette and telling Chas: ‘You nev­er told me he was that fuck­ing good.’” Who knows if Hen­drix knew Clap­ton had strug­gled with “Killin’ Floor” and decid­ed not to try it live. But as blues gui­tarist Stephen Dale Petit notes, “when Chas invit­ed Jimi to Lon­don, Jimi did not ask about mon­ey or con­tracts. He asked if Chas would intro­duce him to Beck and Clap­ton.”

He had come to meet, and blow away, his rock heroes. “Two weeks after The Bag O’Nails,” writes Clas­sic Rock’s John­ny Black, “when Cream appeared at The Mar­quee Club, Clap­ton was sport­ing a frizzy perm and he left his gui­tar feed­ing back against the amp, just as he’d seen Jimi do.”

Relat­ed Con­tent:

Jimi Hen­drix Unplugged: Two Great Record­ings of Hen­drix Play­ing Acoustic Gui­tar

23-Year-Old Eric Clap­ton Demon­strates the Ele­ments of His Gui­tar Sound (1968)

Jimi Hen­drix Opens for The Mon­kees on a 1967 Tour; Then Flips Off the Crowd and Quits

Jimi Hendrix’s Final Inter­view Ani­mat­ed (1970)

Josh Jones is a writer and musi­cian based in Durham, NC. Fol­low him at @jdmagness

You know the sound of the theremin, that weird, war­bly whine that sig­nals mys­tery, dan­ger, and oth­er­world­ly por­tent in many clas­sic sci-fi films. It has the dis­tinc­tion of being not only the very first elec­tron­ic instru­ment but also the only instru­ment in his­to­ry one plays with­out ever touch­ing any part of it. Instead, the theremin play­er makes hand motions, like the con­duc­tor of an invis­i­ble choir, and the device sings. You can see this your­self above, as the instrument’s inven­tor, Leon Theremin, demon­strates his therem­invox, as he called it at the time, in 1954. Speak­ing in Russ­ian, with Eng­lish sub­ti­tles, Theremin describes how the “instru­ment of a singing-voice kind” works “by means of influ­enc­ing an elec­tro­mag­net­ic field.”

Theremin orig­i­nal­ly invent­ed the instru­ment in 1919 and called it the Aether­phone. He demon­strat­ed it for Vladimir Lenin in 1922, and its futur­is­tic sound and design made quite an impres­sion on the ail­ing com­mu­nist leader. Theremin then brought the device to Europe (see a silent news­reel demon­stra­tion here) and to the U.S. in 1927, where he debuted it at the Plaza Hotel and where clas­si­cal vio­lin­ist Clara Rock­more, soon to become the most devot­ed pro­po­nent and play­er of the theremin, first heard it.

Although many peo­ple thought of Theremin’s inven­tion as a nov­el­ty, Rock­more insist­ed that it would be tak­en seri­ous­ly. She appren­ticed her­self to Theremin, mas­tered the instru­ment, and adapt­ed and record­ed many a clas­si­cal com­po­si­tion, like Tchaikovsky’s “Berceuse,” above. More than any­one else, Rock­more made the theremin sing as its inven­tor intend­ed.

The ori­gin sto­ry of the theremin, like so many inven­tion sto­ries, involves a hap­py acci­dent in the lab­o­ra­to­ry. Just above, Albert Glin­sky, author of the his­to­ry Theremin: Ether Music and Espi­onage, describes how Theremin inad­ver­tent­ly cre­at­ed his new instru­ment while devis­ing an audi­ble tech­nique for mea­sur­ing the den­si­ty of gas­es in a chem­istry lab. The first iter­a­tion of the instru­ment had a foot ped­al, but Theremin wise­ly decid­ed, Glin­sky says, that “it would be so much more intrigu­ing to have the hands pure­ly in the air,” manip­u­lat­ing the sound from seem­ing­ly nowhere. Although there are no frets or strings or keys, no bow, slide, or oth­er phys­i­cal means of chang­ing the theremin’s pitch, its oper­a­tion nonethe­less requires train­ing and pre­ci­sion just like any oth­er musi­cal instru­ment. If you’re inter­est­ed in learn­ing the basics, check out the tuto­r­i­al below with therem­i­nist Lydia Kav­ina, play­ing a ‘there­ami­ni’ designed by syn­the­siz­er pio­neer Moog.

In his day, Theremin lived on the cut­ting edge of sci­en­tif­ic and musi­cal inno­va­tion, and he hoped to see his instru­ment inte­grat­ed into the world of dance. While work­ing with the Amer­i­can Negro Bal­let Com­pa­ny in the 1930s, the inven­tor fell in love with and mar­ried a young African-Amer­i­can dancer named Lavinia Williams. He was sub­se­quent­ly ostra­cized from his social cir­cle, then he either abrupt­ly picked up and left the U.S. for the Sovi­et Union in 1938 or, more like­ly, as Lavinia alleged, he was kid­napped from his stu­dio and whisked away. What­ev­er the case, Theremin end­ed up in a Gulag lab­o­ra­to­ry called a sha­ras­ka, design­ing lis­ten­ing devices for the Sovi­et Union. There­after, he worked for the KGB, then became a pro­fes­sor of physics at Moscow State Uni­ver­si­ty.

Theremin nev­er gave up on his elec­tron­ic instru­ments, invent­ing an elec­tron­ic cel­lo and vari­a­tions on his theremin dur­ing a 10-year stint at the Moscow Con­ser­va­to­ry of Music. He gave his final theremin demon­stra­tion in the year of his death, 1993, at age 97. (See him play­ing above in 1987 with his third wife Natalia.) To learn much more about the inventor’s fas­ci­nat­ing life sto­ry, be sure to see Steven M. Martin’s 1993 doc­u­men­tary Theremin: An Elec­tron­ic Odyssey.

And if you’re intrigued enough, you can buy your very own Theremin made by Moog.

Relat­ed Con­tent:

Learn How to Play the Theremin: A Free Short Video Course

Watch Jim­my Page Rock the Theremin, the Ear­ly Sovi­et Elec­tron­ic Instru­ment, in Some Hyp­not­ic Live Per­for­mances

Meet Clara Rock­more, the Pio­neer­ing Elec­tron­ic Musi­cian Who First Rocked the Theremin in the Ear­ly 1920s

Leon Theremin Adver­tis­es the First Com­mer­cial Pro­duc­tion Run of His Rev­o­lu­tion­ary Elec­tron­ic Instru­ment (1930)

Josh Jones is a writer and musi­cian based in Durham, NC. Fol­low him at @jdmagness