For several months, my wife and I had been living in a cozy studio apartment in New York's Financial District while our apartment underwent substantial renovations. All the old furniture was sold or donated, and decades of accumulated stuff was subjected to triage (sell, donate, or store). All my audio equipment, parts, and tools suffered the same fate. Downtown, my listening was via pretty decent headphones (B&W Px8, Audeze LCD-XC) connected to a Mytek Brooklyn+ DAC and my PC. Meanwhile, we were very busy shopping to equip the "new" apartment.

An all-in-one streamer-DAC-preamp would not have held much appeal for me if my old system was up and running. This, however, was a different time, and I was offered the Grimm MU2 for review with ideal timing.

"Hybrid" technology—specifically, mixing tubed and solid state in the same amplification device—stirs a deep desire for many enthusiasts. It has the potential to embody a perfect blend: the tonal liquidity, presence, and spaciousness of tubes coupled with the power and dependability of solid state. It's potentially an end-game technology.

Still, I have long remained skeptical. I am, I confess, a certain kind of audiophile, a blend of purist and traditionalist. I favor older technologies and simpler circuits. Amplifiers—including integrated amplifiers—should be tubed, input to output. Rectification? Tubes of course. I've even entertained OTL designs—the idea of them at least, though my experiences have been mixed.