One to One, March 1999, Issue 104, by Phil De Lancie

Now that DVD-Audio is one step closer to becoming a reality and set to bring back quadraphonic to the home, One to One talks to DTS exponent Robert Margouleff and partner Brant Biles about the 5.1 mastering experience for music.

The field of mastering has seen numerous changes over recent decades, with digital recording bringing both an explosion in the variety of source format brought in for mastering, as wen as a shift in output formats from master lacquers and 2-track cassette masters over to PCM-1630s, CD-Rs and Exabyte tapes. But the basic purpose of the job has remained steady throughout: to optimize the sound of the program and create a master that offers the best possible translation of that program into the listening environment of the end user.

Even as these goals of mastering continue, the years ahead promise further changes as consumers gradually adopt formats that support the delivery of multichannel sound into the home and car. That fact will force reassessment of every aspect of the mastering process, from input and output formats, tools, and the very environment in which the work is done. And because optimization for the home theatre listening environment applies not just to music product but also to sound-for-picture, the opportunity exists for mastering facilities to expand from their core client base in the record industry, into serving the home video industry as well.

A number of leading US mastering houses - from Bob Ludwig's Gateway in Maine to MasterMix in Nashville and Bernie Grundman Mastering in Hollywood - have recognized this opportunity and incorporated multi-channel applications into their definitions of the services a complete mastering facility should be able to provide. At the same time, a passion for surround has gripped others in the recording community, drawing them into a mastering role specifically for 5.1 channel projects.

Among the most prominent of these is Robert Margouleff, whose extensive credits range from co-producing and coengineering two Grammy-winning classics from Stevie Wonder (Innervisions and-Fulfillingness), to more recent work with Wonder and other successful artists such as Boyz II Men (11) and Seal (Prayer For The Dyin').

In recent years Margouleff 's association with 5.1 projects, particularly in the Digital Theater Systems (DTS) format, has brought, him center stage in the budding surround sound scene. Explaining the appeal of surround sound, and why he now devotes most of his energies to it, Margouleff says, "In stereo, we could record amplitude and pitch and duration, but we couldn't record vector information. Now that we have vector back, we have restored a very emotional aspect of the music. I think that's what 5.1 brings to the table."

A collaborative team

For the past 12 years, Margouleff has worked collaboratively on audio production with engineer Brant Biles. As DTS's system brought 5.1 channel music delivery on CD to home theatre owners (who need to use either a DTS-equipped CD player or a CD player with digital outs and a DTS-equipped receiver or separate decoder), the pair began working for DTS and others to create encoded CDs for the format.

"Seventy five to 80% of everything Brant and I have been involved in recently has been in 5. 1," Margouleff says. "We've done some 40 titles in 5.1 over the last three years."

Margouleff and Biles have built up a broad array of surround credits in both popular and classical genres. "One project which we spent a year and a half working on was a 17 CD series of 11 classical titles," Margouleff says. "That was a restoration project of material that had been recorded in quadraphonic in the seventies by Angel/EMI. They were released in stereo, and the quad masters were relegated to the back of the tape library in London."

The recordings, including works by Holst, Mozart, Tchaikovsky and Debussy, were released as DTS 5.1 CDs. "We also did a restoration of the opera Aida, recorded in the seventies with a very young Placido Domingo, conducted by Ricardo Mutti," explains Margouleff. "It was recorded in multitrack, and there are portions that were recorded in the rear of the hall. The 5.1 version really makes you feel like you are inside the performance, carrying a spear and walking around on stage. It's a marvelous experience."

Also released in DTS 5.1 have been contemporary albums including the afore-mentioned Eagles, Boyz II Men and Seal, as well as works by Marvin Gaye (Forever Yours), Paul McCartney & Wings (Band On the Run), Alan Parsons (On Air) and Pavarotti And Friends (Concert For War Child).

"In the Boyz II Men CD we did for DTS," Margouleff says, "there is an accapella version of the Beatles song Yesterday where we put one singer in each speaker, so the blend happens in the room, not in the speaker. And now I want to do some of the Beethoven string quartets using that same approach."

"We originally concentrated on music only," Margouleff continues, "but now we are moving very heavily into sound for picture. We've done six or seven features, music videos and industrial applications for DVD-Video, some in DTS and some in Dolby AC3." Their most recent and highest profile DVD work is on Pleasantville, a feature film DVD-Video for New Line Cinema. "We rechanneled the theatrical mix, which is really a mix designed for viewing a movie in a large hall, into a 5.1 mix that works well for DVD," he says.

Margouleff and Biles have also worked on other DVD projects including a promotional disc touting Columbia Tri Star's DVDVideo releases, a home video release of the film Zig Zag, and Shadoan. Shadoan is an award-winning children's CD-ROM game that was reprogrammed for DVD-Video and released as the first video game with a soundtrack in DTS 5.1 surround.

"What we do for DVD-Video releases is similar to mastering a record," Margouleff says. "A record comes out of the studio all finished, but it still goes to Bernie Grundman or someone for mastering. This is very like dealing with the soundtrack for DVD. We don't fool with the intent of the producer, the director or the original mixer, but we have to be able to enhance it and make sure that it yields its full power in the new format. DVD has three to five times the visual acuity of VHS, so the soundtrack really has to perform and be equally powerful and emotional."

Out of the studio

Initially, Margouleff and Biles did their surround sound work in regular recording studios, which were set up - unlike mastering rooms - to handle the multi-track requirements of working with 5. 1. But that arrangement soon began to strike them as less than ideal, both technically and in terms of the way they like to work. "We spent so much time working in everyone else's facilities," Margouleff says. "And it was always under the gun and under the clock. But we prefer to be more project oriented than hourly oriented."

For his part, Biles points out that size isn't everything. "Everything we are doing in surround is pretty much in the digital domain, so there is no real reason in mastering 5.1 material to have a giant recording console in front of you. We figured that using toady's technology in digital consoles and outboard gear we could put together a really nice facility that would be project effective and cost effective."

Out of this realization was born Mi Casa Studio in Los Angeles, which the two opened as co-proprietors in early 1998. "In the last year we have done all our post-production here, about 80% of our work," Margouleff says. "This way, we can take as much time as we want to work with the project until we feel it's right. Having our own place gives us the liberty to do that. And the room is specifically set up for 5.1, though of course we can do stereo when we need to, for instance for a fold-down mix from 5.1."

Comparing their roles in the operation of the studio, Margouleff says, "We are both creative, both musicians. But Brant does more of the hands-on stuff, the technical work in the studio. I handle more of the strategic, long term planning, and I am the one for the most part who goes out and finds the gigs. So my orientation has been more on the producing side and Brant more toward the engineering. But we both cross over, and we argue with each other constantly about aesthetic judgements, so we have a good time doing the projects."

Biles defines the three main markets for Mi Casa to work, "It is DTS on CD, DTS audio for DVD-Video, and Dolby AC3 audio for DVD-Video." Margouleff adds that MLP for DVD-Audio and/or DSD for Super Audio CD are, "...soon to come, if either of those formats takes off. They all use 5.1 material."

Home surroundings

The common thread linking Mi Casa's target markets is the delivery platform: a surround sound system in the home. "Our work here is only for home theatre," Margouleff says.

So perhaps it is appropriate that not only does the name "Mi Casa" mean "my home" in Spanish, but that the studio is, in fact, literally in Margouleff's house - his living room, to be precise. He says he doesn't mind the imposition on his living space since, "The only reason I have people over is to make music."

"It just makes too much sense to master for home theatre in a living room," Biles offers, "and not in a giant studio which has no bearing on the real world where the material will be heard. Otherwise, it's not going to sound right when you get it into your living room." But while Mi Casa is closer to the intended listening environment than the typical studio, it's not your average living room. The main room is 24 feet long, and 20 feet across at its widest point. There is also a large alcove that Margouleff uses as an office.

Rather than traditional studio wall treatment, the room's furnishings are those of a comfortable house. "There are some tapestries on the wall," Margouleff says, "and a giant open cabinet full of blue china porcelain, which acts as a fantastic diffuser for a whole wall. There is also a lot of overstuffed furniture in the room, which is set up for really good listening. We used the JBL SMAART measurement tool, and the room measured flat, every bit as flat as any major studio would be. It really has a very good feel, and it's large enough that we can get full wave dispersion."

The room's monitoring setup is anchored on the low end with a JBL 4645 subwoofer, a JBL MPX 600 subamp and a JBL DX-1 custom crossover. "There has been much discussion about subwoofer levels" Margouleff says. "I strongly advocate the Tom Holman approach, using in-band alignment of the subwoofer, which emulates the theatrical subwoofer alignment."

Speakers for the five main channels are Genelec 1032A monitors. "The five speakers are all equidistant from a central listening point," Biles says. "The front left and right are 30 degrees off the center line. For the rears, most people use 110 degrees off the center, but we prefer 150 degrees."

The use of the fall size Genelecs for all five main channels, rather than using smaller speakers for the rears as are found in some home theatre systems, reflects the distaste both Margouleff and Biles feel toward the unequal systems that have been marketed to consumers as a way to get into surround.

"It's a transitory approach," Margouleff says, "and we don't advocate it. If the sound is serving the picture and you are oriented in one direction, then the little speakers are fine because you just want to have diffusion of the ambience. And generally the smaller systems utilize a technology called Bass Management, in which the low frequency information that would otherwise be coming out of those channels is directed to the subwoofer instead. So it adapts OK, but it's not ideal. If you want to listen to music, we advocate five equal loudspeakers plus the subwoofer."

As an example of how the unequal systems can limit the use of the rear channels, Biles recalls that he, "recently worked on a 5.1 dance recording with drums in the front and a drum loop in the rear, each equally valuable in their rhythmic contribution to the mix. If you were to stick these drum loops through those little surround speakers, you wouldn't get the volume and fidelity from them."

The same sorts of considerations will likely govern the pair's approach to fidelity allocation in DVD-Audio, which will include the capacity to use higher sample rates and bit resolutions in some channels than in others. "I want equality throughout the space," Margouleff says, "so when I move an instrument through the listening environment it moves accurately from one area to the other. That means the same speakers and the same bit rates all around"

Tools of the trade

While Margouleff and Biles are largely focused on premastering for surround, some of their projects reach further upstream, involving surround mixing as well. The same gear is used for both. Mi Casa's equipment is a hybrid between a pure workstation and a pure console approach. Margouleff and Biles use both a Yamaha 02R II digital console and a SADiE 24.96 hard disc editor, as well as a set of three Finalizer Plus digital outboard processors from TC Electronic.

"We used to do our editing on a Sonic Solutions system at an outside facility," Margouleff recalls. "But when we saw the new 24-bit/96 kHz SADiE at the AES convention in San Francisco we bought it right off the floor. We use it for editing and mixing, and it does everything that we could possibly need it to do. And their technical support is absolutely awesome. You can call them at 3:00 am if you are having a problem, and someone will call you right back and walk you through it."

As for the new system's support for high sample rates and bit resolutions, for the time being Biles does not see that capability as a crucial factor in their everyday work. "24-bit is great," he says "but right now you can~t go out and buy a 24-bit CD. So somewhere along the line you are going to have to dither or use UV22 to get your bit depth down. When 96/24 becomes an accepted consumer playback standard, then it will be crucial to get all the material sent to us at 24-bit and to work at that resolution. But for now, some stuff comes in at 16, some at 20 and some at 24."

Because the bulk of the work is for the 20-bit DTS system, a 20-bit D-to-A converter is normally used for monitoring. For the EQ and dynamics processes that are at the heart of a mastering job, Margouleff & Biles use both on-board and outboard processing." We use the DSP inside the SADiE, which is quite good," he says.

"We also have the three TC Electronic Finalizer Plus units, which have band-sensitive compression, limiting and gating, and also de-essing and parametric EQ."

The studio also recently purchased a Studio Com Model 69 - an outboard monitoring system for use at the output of the SADiE or the Yamaha O2R II when mixing or mastering.

"One thing that's particularly great for us about the SADiE," Biles notes, "is that it's really set up for multitrack editing, so you can edit across all six tracks at once. Also, we have the CEDAR DeNoise and DeClick options for the SADiE, and the DeNoise is awesome. We can plug it into a dialogue channel that might be a little noisy or rumbly, and it just cleans it up. And SADiE does some of its DSP processes like the DeNoise much faster than the other digital audio workstations I've seen." As enthusiastic as Biles is about the SADiE, however, he refers to it as "just one of our tools."

"The piece of gear used to achieve the required result depends what's on the table, and what needs to be done," he says. "We decide which specific tool to use on a per-project basis, or a per-song or per-scene basis. If we want to do something with our hands on a console, we have the 02R here. If we want to work virtually, we use the SADiE. They both offer 5.1 surround busses. It's nice to have that flexibility."

Prepping a 5.1 master

The main tasks associated with surround mastering are overall program level adjustments, level balancing between channels, and enhancement such as EQ and compression. Biles describes the formats of jobs that come to Mi Casa mixed from other facilities. "We usually get the mix at 16-bits, but sometimes at 20-bit using a bit splitter. Then we transfer it either through the 02R digitally, or directly into the SADiE. Then we put the material into the SADiE and use it to automate the levels, which is certainly a lot easier to do in the SADiE than on the 02R."

If the project is a DTS release on CD, the enhanced 5.1 channel mastered program is sent back to DTS for encoding. "We send them a 20-bit DA-88 tape," Biles says, "and they send us back another Tascam tape with the 16-bit DTS-encoded bitstream, or they send us a check CD. We then check the encoded program through our decoder. If everything sounds right, we lay it back into the SADiE and do the PQ coding. Then we send DTS back a DDP tape for manufacturing."

Biles, who used to do encoding for DTS on a Sonic System in his living room (a practice which has since been discontinued in the interests of domestic tranquillity), is very familiar with the DTS codec and has high confidence in its fidelity. "DTS stores the 20-bit signal on a 16-bit CD," he says, "and through the decoding process it comes back out at a full 20 bits. I have actually done experiments where I take a 5.1 mix that has been DTS encoded and unencoded, and I sample-align it and put it 180 degrees out of phase with the original mix that has never been encoded. And with the exception of some phase differences in the subwoofer channel, everything is cancelled out. So the five main channels of DTS give you back pretty much what you put in."

Margouleff is equally enthusiastic about DTS. "DTS is the only one out there doing 20-bit," he says, "and it is wonderful. I have also heard 24-bit DTS, which can be delivered on the DVD-Video format, and it is very comparable with 24/96. We will soon have our own software DTS encoder that will run at 44.1 kHz for DTS CDs and 48 kHz to do audio for DVDVideo. We are going to be the beta test site for it."

Technically, the main difference between a DTS job destined for CD and one destined for the audio tracks of a DVD-Video is the sample rate. The DVD-Video jobs generally come in as DA-88 masters made from the 'mag' of a film's theatrical mix. "Films are all originally mixed for theatrical release" Margouleff explains, "which means for a large hall where the person in the last row of the movie house needs to be able to hear the dialogue. The surround aspect is not emphasized as much as for home theatre. They don't like to put a lot of stuff in the rears. They call it the 'exit light' effect, because people always face where the sound is coming from, and if there's something coming at them from behind they will turn over their shoulders to see it."

The purpose of the mastering job for DVD is to translate the theatrical mix into the home environment. "When you take that soundtrack and you want to put it into a home theatre," Margouleff says, "To serve the film best, the soundtrack must be rebalanced. In a home theatre you are only going to be playing for a few people, so you can work the rears up more and define the space. DVD is its own animal, and requires that the content be designed to fit the format."

As excited as Margouleff is about the future of surround in the home, he is concerned about the impact that competition between rival formats could have on consumer acceptance of the whole notion of music in surround. "The thing that bothers me," he says, "is that every company has its own formula for 5.1, whether it's DTS or Dolby Digital or Sony DSD. And in the process they are diluting everyone's ability to focus on one format and get that format out to the public. I'd like to see 24-bit DTS at 48 kHz, because at least it will be adaptable to the existing DVD players out there, whereas DVD-Audio involves a whole new player. I don't think the public is ready to buy another player to listen to music only surround, and creating all this confusion is really not helping the cause.