Analog or digital? MP3 or CD? Home computer with stock -10db RCA audio inputs or professional modular digital multitrack recorder with +4db balanced inputs?

Steve Carr could easily settle these and other music-nerd debates himself. But the 46-year-old engineer, who operates Rockville’s Hit and Run Recording studio, wants listeners to discern the differences on their own, by comparing the examples on The A/B CD.

The studio proprietor, who did his first professional session in 1979, spent five years recording the CD, which arrays not only analog vs. digital but also tubes vs. solid state, guitar amplifiers vs. computer-modeling emulators, and a Stradivarius vs. a violin that is not a museum piece. There are even contrasting hits of a triangle, “because some people say digital doesn’t capture high-end clarity on the decay,” he says.

Carr expected sound-engineer trade journals and studio-recording schools to be interested in the results. Since the project was completed in 2001, however, he’s mostly gotten the runaround.

“Initially, they say, ‘That sounds great. Send us a CD,’” Carr says. “And then we hear nothing back from them.”

Perhaps some studio professionals are put off by Carr’s own estimation of his project. “Every audio engineering student should have it,” he says of

The A/B CD. “It should be required material for their education.”

Carr is aware that he can come on a little strong. After announcing that “there’s no CD like this on the planet—there’s nowhere else you can hear this,” he chuckles at his own ardor. “Am I too emotional?”

One possible reason the industry has reacted warily to The A/B CD is that its 153 audio snippets don’t necessarily demonstrate the superiority of analog sound or high-ceilinged, high-priced studios. Analog, Carr says, “doesn’t do what it’s purported to do: make the sound bigger, wider, blah blah blah.” A series of comparisons pits Carr’s basement studio against a “professional” one in Atlanta; recordings from the latter sound noticeably flatter and more muffled.

Carr, who has a platinum disc on his wall for his work remastering classic-rock compilations for Time-Life, doesn’t argue that his $50-an-hour studio is better than higher-priced places. Rather, he suggests that the sound of a finished recording has more to do with skills and preferences than with the innate advantage of analog or digital.

“The way these systems record sound is so different. You [might] think it would sound different,” he says. Yet “it’s more a function of what they were doing when they made those original CDs that changed the sound.”

What does matter, Carr contends, is musicianship. That’s why he’s decided to publicize the instructional disc—available online at—to players as well as producers. In a series of comparisons featuring such local musicians as Lisa Cerbone, Billy Kemp, Ruth Logsdon, Bobby Manriquez, and Mark Noone—and Carr himself as “Bassist B”—The A/B CD demonstrates that the snappiness of a recording comes mainly from the performances themselves.

“I had a band,” Carr recalls. “Great female vocalist, great songs. But they couldn’t play. I said, ‘I’ll give you a free recording if you let me use it on The A/B CD.’” So he recorded the untutored group, then did another session after he’d provided some instrumental coaching. The musicians must have noticed the difference, because they refused to allow the tracks to appear on the disc.

Carr still regularly faces musicians who think he—or an analog mixer—can transform their sound. “I record so many ‘Band B’s,” he says. “And it’s out of my control.”

—Mark Jenkins