Gelder made particular adjustments to the sound of John Coltrane's tenor saxophone sound when engineering Coltrane's Impulse Records sessions: "I know the difference between the sound of someone in person and the recorded sound of an engineer. Coltrane's tone was much darker and thicker than the sound on those Impulse! records engineered by Rudy Van Gelder. But maybe Van Gelder chose that sound because he could hear that Coltrane was an alto player first before switching to tenor." Reputation Within a few years of opening his studio, Van Gelder was in demand by many other independent labels based around New York City, such as Prestige Records. Bob Weinstock, owner of Prestige, recalled the following in 1999: "Rudy was very much an asset. His rates were fair and he didn't waste time. When you arrived at his studio he was prepared. His equipment was always ahead of its time and he was a genius when it came to recording". According to a JazzTimes article in August 2016, "jazz lore has formed the brands into a yin and yang of sorts: The Blue Note albums involved more original music, with rehearsal and the stringent, consistent oversight of Lion; Weinstock was more nonchalant, organizing what were essentially blowing sessions for some of the best musicians in jazz history". Van Gelder said in 2012, "Alfred was rigid about how he wanted Blue Note records to sound. But Bob Weinstock of Prestige was more easygoing, so I'd experiment on his dates and use what I learned on the Blue Note sessions". He also worked for Savoy Records in this period, among others. "To accommodate everyone, I assigned different days of the week to different labels". Writer Fred Kaplan has argued that Van Gelder's reputation with the record-buying public was aided by Blue Note Records' conspicuous mentions of Van Gelder on their album covers: "Van Gelder was hardly the only great jazz engineer on the scene in those days; he may not even have been the best. Other stellar figures included Fred Plaut at Columbia, Roy DuNann at Contemporary, Val Valentin at Verve, Roy Goodman at RCA. But the other labels didn't play up their engineers (Columbia covers never so much as mentioned Plaut), while Alfred Lion, Blue Note's proprietor, promoted Van Gelder's sound as a boutique blend—something of a mystique—and the other labels who hired him followed suit, as if to boast that they too