{"product_id":"free-john-sinclair-poster","title":"Detroit Grande Ballroom – Free John Sinclair Concert Poster","description":"\u003cp\u003eAn original Free John Sinclair concert poster promoting a landmark benefit weekend at Detroit’s legendary Grande Ballroom, featuring an extraordinary line-up including MC5, The Stooges, SRC, Scorpion and UP. Held on 24–25 January 1970, the concerts formed part of the growing campaign to secure the release of poet, activist and MC5 manager John Sinclair, who had been sentenced to ten years in prison for possession of two marijuana joints.\u003c\/p\u003e\u003cp\u003eDesigned in the bold psychedelic style synonymous with Detroit’s underground scene, the poster captures one of the defining moments where music, politics and counterculture collided. The campaign to free Sinclair drew widespread support from artists and activists, culminating in the famous Free John Now Rally later that year featuring John Lennon, Yoko Ono and Stevie Wonder.\u003c\/p\u003e\u003cp\u003ePosters from the Grande Ballroom remain among the most sought-after pieces of American rock ephemera, documenting the venue that helped launch Detroit’s influential garage and proto-punk scene.\u003c\/p\u003e\u003cp\u003eThis example comes directly from the personal collection of Mary Cobra (Mary Ramirez), founding guitarist of The Detroit Cobras, whose archive reflects a lifelong connection to Detroit’s rich musical heritage.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eKey Details \u0026amp; Collectability\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eOriginal Free John Sinclair Grande Ballroom concert poster.\u003c\/li\u003e\n\u003cli\u003ePromotes performances by MC5, The Stooges, SRC, Scorpion and UP.\u003c\/li\u003e\n\u003cli\u003eDocuments a pivotal moment in Detroit’s counterculture and rock history.\u003c\/li\u003e\n\u003cli\u003eFrom the personal collection of Mary Cobra (Mary Ramirez) of The Detroit Cobras.\u003c\/li\u003e\n\u003cli\u003eA highly collectible piece of Detroit rock memorabilia with strong appeal to fans of MC5, The Stooges and the Grande Ballroom.\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Mary Cobra","offers":[{"title":"Default Title","offer_id":54998481666377,"sku":"NYC_MC_014","price":600.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0064\/9992\/files\/Untitled-04August2026at11.27.14-6.png?v=1785926753","url":"https:\/\/waxpoetics.com\/products\/free-john-sinclair-poster","provider":"Wax Poetics","version":"1.0","type":"link"}