There's a reason why David Letterman is the only network talk-show host with a best-selling music-compilation CD out: artists seem to want to go on that show more than any of the other late-night talkfests. Harvey Goldberg, who started working with the show 12 years ago and has mixed the music for the show exclusively for the last five years, thinks he knows why.

“I think music artists believe that this show takes more care with the music than any other television show,” opines Goldberg, who says his background in recording studios as a mixer helps set him apart from engineers who specialize in broadcast audio, and that that sort of distinction is pervasive on the Late Show sound crew. “Think about it – Dave's sidekick, Paul Shaffer, is a musician. He's like Doc Severinson and Ed McMahon rolled into one. And Dave genuinely likes music. It's not just part of the show – it's part of his life.”

Letterman has been known to discover an artist or two on his own and have them on the show, and in a city that has had no country music station since the turn of the century, the talk show host has been a champion of the genre, bringing on artists like Faith Hill and George Jones.

That, says Goldberg, is why acts that have historically shied away from television will do Letterman. Pearl Jam not only played the show several times but also once stayed and did a 45-minute live concert performance from Ed Sullivan Theater, where the show is taped, that was streamed over the Internet. Classic blues, R&B and rock musicians, such as Solomon Burke and Allan Toussaint, regularly sit in with the house band. “Plus, Dave is from Indiana – the Midwest – where you get all kinds of music. I think that's another reason the show's music is so eclectic.”

It also sounds good. Goldberg has an 80-input SSL G Series console. That's significantly larger than you'll find on most other variety shows, and with good reason: he has to mix two bands a night: the featured music act and the eight-piece CBS Late Show Orchestra. He splits the console down the middle between the two, 40 inputs each, and the analog console largely defines how he approaches the music mixes. He records each show to two 24-track, 24-bit/96-kHz RADAR units because, he says, “it's the closest thing there is digitally to the warmth of an analog tape deck. I don't need all the editing and other features that would come with Pro Tools, and as a result I also have a much more stable recording platform, which I like for broadcast. Plus they sound good, they're easy to use and the they go up to 192 kHz, which is good for archiving.”

Goldberg also prefers analog processing for the show's music, using the console's dynamics, EQ and mic-pre's. These are augmented with the kind of outboard processing more common to recording studios than broadcast booths, including a pair of (reissue) LA-2A compressors, and Neve 43609C and 33609J compressors. “I like these better than plug-ins, and I think bands feel more comfortable around gear like this.”

Not that Goldberg gets that many visitors to the music mixing control room, located in the basement of the theater. The show's second audio control room, around the corner from Goldberg's studio, is the production mixing room, which takes his stereo music feed and sends it on to the main CBS uplink for broadcast. Underscoring the show's commitment to music, Goldberg says he has the equivalent of a “gentlemen's agreement” between his control room and the other one. “They don't add any additional compression to the music mix,” he says. “What happens once it reaches the broadcast transmission point, I don't know, but I do know that the music leaves here with a lot of the dynamics intact.”

It's also has little in the way of post production. Monitoring over a newly installed pair of Klein+Hummel 0300D speakers, Goldberg also tracks the feature music performances with the console automation. Since the music almost always closes the program, he'll play it back from the automation immediately after the close, listening for any problems or working from notes he makes during the performance. Most of the musical acts' hardware is modularized during their 45-minute soundcheck/rehearsal slot, with amplifiers, drums and microphones ganged into mults on the movable risers and plugging into snakes leading to the control room. (The fact that the music mixing control room is almost directly underneath the stage keeps the signal runs short, as well.) Despite how it looks on television, the stage is actually quite small, and the musical acts' sets are struck after rehearsal and wheeled together during the long last commercial break. (By contrast, Late Night With Conan O'Brien on NBC incorporates the music set into the show's look, placing it behind a mesh curtain.)

Mixing music on a variety show has its peculiarities. While the equipment in the control room is top shelf, Goldberg will almost always resort to the workhorse Shure Beta 58 dynamic microphone for lead vocals. “In an environment like this you're going to get an insane amount of bleed,” he explains. “The 58 is not a particularly sensitive or bright-sounding mic, so what gets in there from the rest of the band isn't as problematic.” He also always does sound checks with the lead vocal channel open. “It's always open during the performance, and as a result what comes through there from the rest of the band has a big effect on the overall sound,” he says. “If you were to mute the vocal [channel] during a playback you'd definitely hear a difference in the overall sound. I also tend to keep the individual EQ less bright than you would otherwise, because the open vocal microphone is going to brighten the sound up.”

If there is a problem with a performance, Goldberg reports it immediately to either Sheila Rogers or Sheryl Zelikson, the music segment producers, who are holding up striking the set for just that reason. The rest of the audio staff, including production mixer Kevin Rogers, front-of-house mixer Tom Hermann, monitor mixer Larry Zinn and A2 Pete Pelland, also hold position. (This especially crucial on Monday nights, when the show does a double taping.) Small problems, like a disconnected cable that cuts off a guitar solo or a direct box on the fritz, can be fixed with a quick overdub in the control room. “If the band doesn't panic, we can usually fix it,” he says. If the problem is more extensive, or particularly if there's a problem with the vocal performance, the band is given a chance to perform the song again, sans audience. “But the whole point is to make it sound not posted,” he says. “So much of the music on television sounds too perfect. The musical performances on this show are meant to be live performances.”

Goldberg may not need to the fix the performances of the crack house band, but he finds that mixing the same band he works with every night is often more of a challenge than the band he met 20 minutes ago. “When Paul's band is on, all the microphones are on – Dave's lavalier, the audience mics, there's microphones all over the place. When the featured musical act is on, everything else is off, so it's a lot more controlled of an audio environment. Plus, I never know which mics are on at any given time during the show. The production audio is opening and closing channels as the show moves along. As they open and close, I have to constantly change my balances. And there are little things you discover, like the fact that the trumpet often shows up in Dave's lavalier microphone because of its volume and the way the bandstand is oriented. It's a roller coaster.”

It might become more so when CBS decides to take the show completely digital. Late Show now uses Dolby Surround, a matrixed LCRS format, with the surrounds created from manipulated phase information from the two-mix, and which is applied upstream from the taping prior to transmission. Goldberg says he's researching consoles now, even though there's no specific timetable for the transition. “What I know for sure is that I'll want to use a console with dedicated channels, just as I do now,” he says. “It's broadcast and it's live music, so I can't be paging through layers of a console. I need my channels and my mic-pre's and processing right in front of me at all times.

“I'm on old-school record guy,” says Goldberg, whose record credits include Kool & the Gang, the Ramones and Marianne Faithful. “We're doing music on television not much differently than we did it in recording studios 20 years ago. But that's why the music on this show is so real.”