If album sales, longevity of career, position on the leading edge of audio technology, reputation in the music business, and involvement in many of the most important albums in history are the measurements, Bob Ludwig is the GOAT (Greatest Of All Time) of music mastering.

"I'm an old goat, anyway," he joked during our multiday, many-hours conversation, centered around his recent retirement announcement and his five-plus decades as a mastering engineer.

If Bob Ludwig is the Michael Jordan of music mastering—and the case can definitely be made—then this is big news. I'll repeat it for emphasis: Bob Ludwig is retiring. Ludwig stopped taking new work on June 30, 2023.

If music reflects the life of the person who created it—if, for example, we can hear Mozart's inner turmoil in his operas—then Warren Zevon's song catalog is uncommonly revealing. Headless mercenaries, killer rapists, and yes, impeccably dressed werewolves with a taste for pina coladas are all part of the colorful world of WZ's twisted imagination and especially of his masterpiece, 1978's Excitable Boy, recently reissued by Mobile Fidelity on two 180gm LPs cut at 45rpm.

The first true high-end component I owned was an Audio Research SP-10. I reviewed this two-box, tubed preamplifier in the May 1984 issue of the English magazine Hi-Fi News & Record Review. "The SP-10 presented [recorded] information in a more coherent, less distorted manner than any preamp I've tried," I wrote in the review, concluding that "the SP-10 made me realize how many good records I owned." I purchased the SP-10 and brought the preamplifier with me when I moved to the US. Four decades later, I still have that SP-10. "Every now and again, when I want to be reminded of the magic it brings to my music, I set it up, plug in the tubes, and spend an evening spoiling my ears," I wrote for an article in Ken Kessler's 2020 book on the history of Audio Research.

I was planning to review the latest product from Audio Research, the I/50 integrated amplifier, which costs $5500, earlier this year. However, with the uncertainty back then about the company's ownership, I postponed the review. When the news broke in June that Audio Research had been acquired by AR Tube Audio Corporation, a privately owned corporation that includes Valerio Cora of Canadian loudspeaker manufacturer Acora Acoustics as a director—see Industry Update in this issue—I unboxed the I/50 and set it up in my listening room.