YOU ARE SURROUNDED

Surround Sound Explained - Part 8

Published in SOS March 2002
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Technique : Recording/Mixing

We hear from more surround producers working at very different ends of the music business to see how they've created working surround systems, and how they make use of 5.1 at the mixing stage.

Matt Bell

As promised in the last instalment of this series, this month we continue our surround case studies and hear from two more producers about their experiences recording and mixing in 5.1. It would be hard to find two more contrasting setups than those of the people we've been talking to this month. On the one hand, there's veteran US producer Elliot Scheiner, who's been producing 5.1 mixes for DVD release for several years now, amongst them Van Morrison's Moondance, The Eagles' Hotel California and live reunion concert Hell Freezes Over, Sting's Brand New Day, REM's Reveal, and Steely Dan's Gaucho and recent album Two Against Nature. Elliot has also recently finished work on a 5.1 remix of Queen's A Night At The Opera album, which includes the classic 'Bohemian Rhapsody', and this project will be the subject of a dedicated SOS feature very soon.

Arguably at the polar opposite end of the spectrum is the 5.1-capable setup that has been created in a far-flung corner of rural Scotland at a project studio which is mainly used for recording folk music, Arc. Producer Gavin Sutherland (originally one half of the '60s folk duo The Sutherland Brothers, and co-author of Rod Stewart's '70s hit 'Sailing' among many other records) and studio engineer Jim Hunter realised that without too much expense and effort, they could upgrade Arc's existing multitrack digital recording studio and make it surround compatible (see the 'Surround At Arc' box on the next page). By April last year, they had the surround aspects of the studio up and running and were making 5.1 recordings, including a demo piece for guitars, piano and bass composed especially to test the surround facilities. They plan to begin giving classes on 5.1 production later this year.

So how do these very different producers go about the process of recording for surround? As with stereo recording, naturally, everything begins with microphones, and as explained in previous parts of this series, anyone planning to record in surround has a choice. Just as in stereo recording, where you can either use a stereo pair of mics to create a true stereo recording of something, or record in mono with one mic and then create a convincing soundstage with panning at the mixing stage, so too with surround. You can either employ dedicated surround microphones such as the Soundfield mic mentioned in part three of this series, or a five-mic surround array as explained in part four, or alternatively you can use ordinary mics and sort out the panning to the appropriate speakers at the mixing stage.

Gavin Sutherland (left) and Jim Hunter (right) in the control room at Arc Studios.

Perhaps unsurprisingly, given that dedicated surround mics and mic arrays are expensive, Gavin Sutherland and Jim Hunter at Arc opt for the latter option, and use their standard Electrovoice RE20s and Neumann U87s. Separate stereo and surround mixes can then be made from the same multitrack recordings. "Most of what we do, we mike up the same, whether we're recording for stereo or 5.1... and then it's just a question of where it's all routed at the mix", explains Gavin. They achieve this by close-miking players and also using a couple of ambient mics which can be placed in the surround channels at the mixing stage to give a greater sense of the environment in which the recording was made — more on this at the end of this article.

Despite frequently having large budgets at his disposal for his recording and mixing projects, Elliot Scheiner takes the same approach. "I still pretty much mike everything the way I always have, although I have experimented with multi-mic recording on certain instruments, like drums and percussion. I can't imagine trying to do that with all instruments, though. Most of the technique comes about in the mix; I still love to have mono signals pocketed around the field."

Rather like Peter Cobbin, the Senior Engineer at Abbey Road interviewed in the last two instalments of this series (see www.soundonsound.com/sos/jan02/articles/surround6.asp and www.soundonsound.com/sos/feb02/articles/surround7.asp), Elliot Scheiner has been working with 5.1 surround for a relatively long time, and remembers well the early days of the mid-'90s, before anyone had started seriously manufacturing gear suitable for surround production. His first few surround projects were mixed from analogue multitracks on a Neve analogue desk which had sufficient auxiliary busses to produce a six-channel surround mix, and he has mostly managed with analogue consoles such as the Neve VR and various SSL desks since, avoiding computer-based systems such as Pro Tools completely. Recently he has started to use a Sony DMX R100 digital desk to more easily achieve effects requiring very complex automation, such as rotational panning effects. In his most recent work for Queen, he has done some editing on Steinberg's Nuendo computer-based digital workstation (as this was the medium on which the multitrack recordings were supplied), and he intends to use Nuendo throughout his next, as-yet-unrevealed project — but this will be the first time he has worked entirely within the digital domain.

"I'm for the most part an analogue geek, and I have used both Neve and SSL desks to do surround mixes. Steely Dan's Gaucho and Two Against Nature were mixed on a Neve 8078. It's a tough way to go about mixing surround, but it does work. That particular console had a quad buss, so it was easy to take care of the Left, Right and Surrounds. The Centre and Sub channels were a little more tricky; I used two aux busses, but they were always fed by a fader so I could control the signal to those sends. It left me with less auxes for effects, but those records were fairly minimal in that area anyway.

Surround At Arc     Arc Studios is located at the North East Folklore Archive (above), a resource centre established by Aberdeenshire County Council to preserve Scotland's spoken history, folk music and heritage. Part of this task involved setting up a music recording facility so that the traditional melodies and songs of the region could be recorded for posterity. As a well-known local musician and producer, Gavin Sutherland was approached in 1997 by the director of the centre to choose the gear needed for the studio, and has remained closely associated with it since. The studio was eventually based around two Soundscape digital recording systems and a Soundcraft Ghost mixing desk, with a couple of Neumann U87 and Electrovoice RE20 mics. Early last year, Arc's engineer Jim Hunter was invited to an AES 5.1 surround demo at Abbey Road in London. Enthused by what he saw, Jim spent the long drive back up to Scotland mentally disassembling Arc in his head and working out what extra equipment would be needed to enable it to make and mix 5.1 recordings, and by the time he arrived, he had it all worked out! Fortunately, with the exception of some extra monitors, not much outlay was required, as the more complex bussing requirements needed to route several channels to six master busses instead of two could all be taken care of in the Soundscape system, as explained in the main part of this article.

"I prefer using analogue consoles because of the sound, but I make use of everything available to accomplish what I need for a surround mix; I added the Sony R100 console so that I can implement surround panning fairly easily. Some of the newer consoles do have surround panning, but it's still not as easy as it is on the Sony. The one thing I really keep away from is the larger-format digital consoles."

At Arc, Gavin Sutherland and Jim Hunter have ingeniously stretched the capabilities of the studio's 24-track PC-based Soundscape setup and Soundcraft Ghost mixer to give themselves the required number of busses for 5.1 production. The studio's two Soundscape hardware I/O units each offer two stereo outputs (four individual outs), making for a total of four available stereo output pairs. The Soundscape system's recording tracks 1 to 4 are assigned to the first output pair, tracks 5 to 8 to the second, and so on, up to 16 tracks. The first of the Soundscape system's output pairs is patched into the Ghost and is routed to its Aux busses 1 and 2. The second Soundscape output pair drives Ghost Aux busses 5 and 6. Auxes 1 and 2 are then used to drive the Left and Right channels of a surround mix, while auxes 5 and 6 drive the Left Surround and Right Surround channels. The third output is assigned to Ghost auxes 1 and 5, and the fourth to auxes 2 and 6, so that the third output handles anything that is to be panned front to back on the left side while the fourth output handles anything that is to be panned front to back on the right. "Essentially", explains Jim Hunter, "each of the stereo Soundscape outputs drives a left-right pair in a different plane: Front Left and Right, Rear Left and Right, Front Left and Rear Left, and Front Right and Rear Right." The faders on the Ghost can therefore be left unchanged, and all level and panning can be handled from the Soundscape (the left-right panning on the tracks assigned to the third and fourth outputs determines the front-rear balance of those channels, with left equalling front and right the rear).

The output of Ghost auxes 1 and 2 is then recorded to tracks 1 and 2 of a Fostex DMT8VL hard disk recorder sync'ed via timecode, and auxes 5 and 6 are recorded to tracks 5 and 6 of the Fostex. Any lead instruments or vocals destined for the Centre channel are recorded separately, directly from the Soundscape to Track 3 of the Fostex. Low-frequency material destined for the Sub (LFE) channel also goes directly from the Soundscape to Track 4 in a separate pass. The result is a six-channel surround master on the Fostex. As this piece was being written, Gavin and Jim were planning to replace the Fostex with an ADAT, so that the six-channel master can be recorded to removable ADAT tape.

Elliot Scheiner has more options at his disposal for mastering, and makes full use of them. "I record all of my multi-channel mixes to multiple formats. I always use a Studer two-inch analogue machine with an eight-track head stack on it, in conjunction with Dolby SR. That is my main format, but I also record to an Alesis HD24 with Swissonic 24-bit, 96kHz A-D converters. Lately, I have tried recording back to separate tracks in the Nuendo system with the same Swissonic converters, but my preference so far has been the analogue mixes. I think most people are in agreement as far as digital is concerned that 24-bit is superior, but as far as the sampling frequency goes, the jury is still out. DVD-A is 96kHz and if that's what is needed to market the new technology, then I'm for it."

Just as with surround mics and techniques, prospective surround producers can either use stereo effects units and place them in the surround soundstage at the mixing stage, or make use of the growing number of multi-channel effects units, such as Lexicon's 960L and TC Electronic's System 6000. At Arc studio, however, Gavin and Jim make do with a Digitech Studio Quad and Yamaha REV500, plus plug-ins within their Soundscape system, and these suffice for the folk recordings that make up most of their work.

Unsurprisingly, Elliot Scheiner has tried various bespoke surround effects solutions, although he also continues to use stereo effects such as TC Electronic's M3000. At the moment he favours two particular units, Eventide's Orville and Yamaha's new SREV1. Both of these can be used in stereo but also offer a four-channel mode for easier surround compatibility.

The control room at Arc, with (left-right) Tannoy monitors (and temporary Technics SB3130 speaker for the Centre speaker, on an equally temporary stand!), Soundcraft Ghost desk, Soundscape system and host PC, Tascam DA20 MkII DAT, Yamaha REV500 multi-effects, and Fostex DMT8VL digital multitracker.

As detailed in part six of this series, surround monitoring is more involved than simply adding three more speakers and a subwoofer to your stereo monitoring system — driving them from your existing system can prove a real headache, due to the lack of built-in means to connect multi-speaker arrays to most mixers and the consequent lack of a suitable overall level control. Third-party surround monitor control boxes are available, but not at particularly project studio-friendly prices. Once again, Gavin Sutherland and Jim Hunter at Arc have found an ingenious (and inexpensive) solution. Arc already had two Tannoy System 800 and two Wharfedale speakers for stereo monitoring, so by supplementing these with a cheap Technics SB3130 for the Centre speaker from an old hi-fi setup of Jim's, they at least had the right number of speakers. Solving the problem of how to connect them was harder, but salvation came in the form of an affordable Denon surround amp, the AVR2801. This has individual inputs to connect all the individual track feeds from the Fostex DMT8VL, plus discrete connections for a complete array of surround speakers and one master level control, so that the overall monitoring level can be easily adjusted independently of the individual track levels on the Fostex. Jim: "That's invaluable. We got it from a music shop in Edinburgh, and it wasn't even that expensive — about 300 quid. There was a more expensive one higher up the range, but we didn't need it!"

As part of the refit for surround, Gavin and Jim purchased five KEF Q55.2 monitors and a Velodyne CT100 subwoofer, and arranged them in a surround configuration in the live room at Arc. The Denon amp is connected between the outputs of the Fostex DMT8VL and the temporary Tannoy/Wharfedale/ Technics surround monitor setup in the control room when Gavin and Jim are mixing from the Soundscape through the Ghost to the Fostex. Then, after the Centre and Sub channels have been added to tracks three and four of the Fostex, the amp is connected to the KEF monitors so that the completed 5.1 mix can be played out into the recording room.

Once again, Elliot Scheiner is fortunate enough not to have to employ such workarounds; most of the studios at which he mixes have proper facilities to connect surround monitor arrays directly to the mixing console, and when he works in places that don't, he employs a Studio Technologies 68A/69A monitor control unit (which, at a UK price of £1699 including VAT, costs more than Gavin and Jim's entire range of control-room monitors!). However, Elliot's monitors of choice for surround work may surprise some readers: "I have been a Yamaha NS10 user for 15 years, and I still believe it is the most honest speaker there is. I mixed The Eagles' Hell Freezes Over and Steely Dan's Gaucho into 5.1 with NS10s and two M&K subs. After that, I moved over to using KRK E8s and their Rok Bottom sub, but in the past year, I've switched to Yamaha MSP10s with the matching sub. I feel that the MSP10 is pretty honest, and I'm getting great work done on them!"

Last month's instalment of this series detailed how producers Rik Ede and Peter Cobbin were approaching 5.1 mixing, as well as some of the difficulties they had to contend with. Like them, Gavin Sutherland, Jim Hunter and Elliot Scheiner are all enthused by the new technology, and the sense of freedom it affords them. Elliot has gone on record saying that music takes on "an entirely new life" in surround, and although he concedes that there are still a few matters to iron out, such as a standardised sampling rate for surround mixes, he also plays down these remaining issues. "The most important thing is to let the consumer hear how wonderful surround is!" Gavin Sutherland is similarly positive: "I think this is easily as big a move as it was from mono to stereo. When you get thinking about surround production and arrangement, you're no longer just thinking about when certain instruments should come in, but also where! In stereo, you're much more limited in that respect, because there are so many conventions about where you're supposed to put things... if you put, say, your drums all off to the left in a stereo mix, most people would think you were really daft."

DVD Authoring     Due to the current high cost of DVD writers and authoring software, Arc studios has steered clear of DVD authoring, but Gavin and Jim are currently holding talks with a nearby record company, Grampian, which does have the necessary hardware and software. When they replace the Fostex DMT8VL with an ADAT, the pair hope to use Grampian as their mastering house, and thus begin offering a complete surround production service, completing the 5.1 mixes to ADAT at Arc, and then sending the tape on to Grampian so that the finished DVD can be burned there. Elliot Scheiner also has little to do with the final stage of DVD production, nor with whether AC3 or DTS compression is used to fit his mixes onto DVD-Video discs with visual material, as he is satisfied that either method is acceptable (see last month's instalment for more on why this is necessary). "I agree with Peter Cobbin at Abbey Road that you just have to deliver the best 5.1 mix you can with at the highest resolution. I don't concern myself with the encoding process except to approve it when it's done, although I do still believe that DTS is the superior method."

So what are they doing in their mixes, and what do they avoid? Elliot started mixing for surround with several live projects, and often attempted to recreate a live soundstage on these, placing the principal musicians across the Left, Centre and Right channels, and putting supporting musicians in the Surround channels to give the listener a stage-based perspective. Since moving to mixing more studio-based projects, where there is no need to place instruments 'realistically', he admits that "anything goes. Studio recordings are usually the most fun and the most creative. Having said that, in most cases, I will put the drums and bass and lead vocals in the front. I do put drums in the rear on occasion; one of the cuts on Van Morrison's Moondance is like that." The only problem he notes with use of the Surround channels is when placing overdubs there, such as horns. Unlike in the narrower stereo soundstage, it's occasionally possible to spot the changes in the ambience of a 5.1 mix when overdub channels punch in and out on the surrounds. Elliot gets around this by assigning more tracks to the surround channels, such as backing vocals.

Even more strongly than Peter Cobbin, Elliot prefers not to feel constrained by how well his 5.1 mixes will fold down into stereo, feeling that a separate stereo mix should be included on DVDs for those who don't wish to or cannot listen in surround. "I would try to fight for no fold-down being allowed; I'm very opinionated on this issue. A fold-down is extremely dependent on how you've arranged your 5.1, and if you've done your job properly, it'll never come close to the original stereo mix — an enormous amount of time and care usually goes into that. Just put in the original stereo mix!"

On use of the Centre and Sub speakers, Elliot has been advising caution since his first surround projects. "You don't know how people's home systems are configured or if they're using full-range speakers all around or not, so I just use the Centre to accent vocals, kick, bass, snare and any other instruments that need emphasis." The same goes for the LFE channel, which Elliot only uses for occasional accent on low-frequency instruments which he's also placed elsewhere in the mix.

Aside from the odd bit of wild experimentation in their surround test compositions (see the 'Surround Panning' box), Gavin and Jim's foray into surround has thus far been deliberately low-key, as Jim explains. "Most of the people we've recorded here, being traditional musicians, like everything to be set up as it would be on the stage, and left there." And the sparseness of the material doesn't usually lend itself to dramatic surround treatments either, as Gavin explains: "Obviously, in the movies, you can see the bomber swoop down over there and see the dam blow up over here, and try to set up the sound accordingly, but if you've got a singer/songwriter with a harmonica and an acoustic guitar, what are you going to do with that?

Arc studio's Soundscape hardware units (left), with the stereo power amps on the right. The all-important Denon AVR2801 surround amp is in the centre.

"If there's just one folk player and a guitar and his harmonica, we'll use one mic on him, and put that centre forward in the surround mix. We'll also use two other mics to capture the ambience of the studio, and put the signals from those in the rear Surround channels. That way, it's quite subtle, but you do get a nice enveloping effect, and it's definitely not as good when you turn the surround channels off.

"If, on the other hand, you've got enough players that you can place each of them in different positions around a 360-degree soundscape, then you can make it sound as though you're sitting in the middle of a folk club and the players are all around you. Say you've got a mandolin, fiddle, a bodhrain player or a percussionist, and maybe an accordion player. We'd just put a mic on each of them, and put up a couple of ambient mics as well, and then route everything to the appropriate channels for placement — you more or less copy where they sit when they're playing. It's pretty straightforward really."

And what of the Centre channel? Again, Jim and Gavin's use for these channels is logical given the type of material they work with. Gavin: "Obviously, if you've got a vocalist or lead instrument, the thing to do is put them in the Centre channel." Jim: "Sometimes, I do put a little of it into the Surrounds as well. That really seems to bring it out of the speakers. It sounds really flat when you take it out of the rears after that."

As for the sub, it hasn't seen much use yet — hardly surprising, given the amount of sub-bass emanating from the average folk ensemble. Jim: "In the Surround demo pieces we've done here, we fed the sub with the bass, the bass drum, and the low end of a piano. But the commercial music we're recording here, from traditional instruments like fiddles and accordions, doesn't really have that much in the way of low frequencies. Put it this way — we have the facility if it's required."

One of the benefits of the Arc approach is that the signals Gavin and Jim record can be used to make a standard stereo mix too, though Jim treats this as an entirely separate mixing process. Sometimes, he finds that including the signals from the ambient mics causes phase problems when mixed with the direct signals for a stereo mix, in which case he simply doesn't include the signals from the ambient mics in the stereo version. Stereo mixes can be burned directly to CD-R from Soundscape via Arc's HHB CDR800, so that groups can take away a finished stereo CD straight away, and no further mastering out-of-house is necessary.

Gavin cheerfully admits, "If that surround setup Jim saw down at Abbey Road is a top-of-the-range BMW, what we have here is more like a Morris 1000 — but it does work!"

Next month, we'll take a look at some of the software you can use for surround work on computer-based systems.

Surround Panning     One of the trickiest effects to achieve manually in 5.1 mixes is surround panning. Performing the level changes required to achieve the illusion of a smooth rotation around the speakers is virtually impossible in real time — the human body simply doesn't have enough arms — so most people resort to technology. Surround panners exist for Digidesign's Pro Tools (such as Kind Of Loud's Smart Pan Pro plug-in) and MOTU's Digital Performer, and Elliot Scheiner, as already explained elsewhere in this article, resorts to using the automatic surround panning facilities in his digital Sony DMX R100 desk, but how do the Arc team go about it? As Jim Hunter explains, most of the music recorded at Arc isn't suitable for that kind of treatment, but they certainly can achieve the effect if they want to, and have done on the surround demo pieces he and Gavin have been experimenting with. "On one of our demos, we had a keyboard line move around the room for a few bars. We copied the keyboard onto several tracks in Soundscape, assigned them to the different master busses and put fades on in the right places so that you got an illusion of movement from one speaker to another. So you might start it on one track assigned to the front left speaker, then fade that one off as the track assigned to the rear left faded up, then fade that off and fade up the rear right... and so on. It seemed to work fine, though it had to be done in Soundscape; you couldn't do that on the Ghost, it'd be a nightmare! So if someone came to us with a piece of experimental electronic music and said 'I want it full of panning', we could do it. It'd be a bit fiddly, but we could do it."