One potential problem with recording room ambience is that of achieving the correct character — after all, real rooms don't come with the adjustable parameters you find on digital reverberators. Craig Leon puts it succinctly: "If you're trying to get an organic [drum] sound, the room means so much more than which specific mic you're using."
For this reason, those people who like their reverb real tend to be pretty proactive in capitalising on all the different acoustic spaces available to them, seeking out the best sound to suit each track. Here's Ben Hillier talking about recording Blur's album Think Tank, for example: "[The reverb in the main live room] was mental and we wanted to get a much drier sound. The only place to do that was outside, which is about as dry as you can get. Those were the options — either completely dry or completely roomy. There were some smaller rooms there as well, including a derelict bathroom that was great for vocals."
A tried and trusted technique is to record close mics in one space while simultaneously recording ambient mics in a more acoustically reflective adjacent area. Corridors are a firm favourite, with Rich Costey, Simon Dawson and Ben Hillier all taking advantage. In the last case, this trick enabled Hillier to record the drums for a Tom McRae album in his small programming room: "If I needed more ambience, I'd just open the door to the corridor and stick a mic down the end. It makes for a more colourful sound." Stairwells have also served faithfully on hit albums from engineers such as Bob Clearmountain (Roxy Music's Avalon), Jason Corsaro (Madonna's Like A Virgin), Don Smith (The Rolling Stones' Voodoo Lounge), and Al Stone (Jamiroquai's Supersonic).
Bathrooms are a similarly frequent choice, the unique live character imparted by the typical hard tiled surfaces getting the thumbs up from people like Joe Barresi, Jason Corsaro, Jack Douglas and Ben Hillier. A recurring refrain here is that they're particularly good for vocal recording, a finding corroborated by Steve Bush's experiences recording the Stereophonics' Kelly Jones in the small stone room at Real World studios: "The vocals had a really rich enhanced sound... All the best singing went down in this particular room, because of its sound... The ambience helped the vocals sit in the mix well, because the tone of the space is just right."
Even if the right ambience isn't immediately on hand, though, that doesn't stand between real professionals and the sound they're after — they just roll their sleeves up and set about altering acoustics with whatever comes to hand. For example, Bob Clearmountain got creative to achieve the rock drum sound of Brian Adams' Reckless despite a dead-sounding live room: "I walked around and found a door off to the side of the studio that led into a loading bay [which] had this incredible sound... We decided it would be kind of awkward to have Mickey the drummer in a whole different room, so I set up the kit right in front of the door, got these gobos on which one side was a real hard wood surface, and made a big funnel-shaped device that focused the sound through the door into the loading bay. I put a couple of room mics in there, and that's how we got our big rock drum sound. Then I found these big 4' x 8' pieces of sheet metal [which we put up] on the walls around where the drums were set up, just to try to get some ambience... It was interesting, to say the least, and was further proof that you can pretty much achieve anything anywhere."
This is by no means an isolated example. Chris Tsangarides was using screens to simulate a bass bin when he came up with his 'vortex' technique for guitar recording, while Hugh Padgham turned to a variety of impromptu and commercial acoustic treatments when keeping reverb under control for The Police: "Apart from the old thing of closing curtains, putting rugs on the floor, and gaffer-taping bits of carpet onto the walls, we also used studio screens, as well as things called Tube Traps. If, for instance, someone is playing an acoustic guitar in a quite reverberant room, you can surround the microphone, the player, and the instrument with some of these Tube Traps and they'll radically change the reverberant characteristic of the sound."
The search facility on the SOS web site is an easy way to access a huge archive of interviews with many of the world's top producers. Mike Senior's research for this article was based on published interviews with 70 of the world's top producers, and if his article leaves you wanting to read more about their recording and mixing techniques, you can find the interviews either in Howard Massey's Behind The Glass (details elsewhere in this article) or in the Sound On Sound online article archive at www.soundonsound.com. Just enter the producer's name in the search box and click on the link to the relevant interview, as indicated in the screen below.
There are lots of examples of engineers using electrical means to tailor the room sound as well. For example, when Chris Kimsey had decided to record The Rolling Stones all together in one room for their hit 'Start Me Up', he used a PA fed from the close mics to boost the level of ambience on Charlie Watts' snare drum, helping it match the ambience from several cranked guitar amps. And this technique is used by a number of different producers, even when there are no other instruments set up: Steve Churchyard fed some snare signal through a small Yamaha PA when engineering the Pretenders, while Chris Fogel and Jack Douglas both describe using powered subwoofers to fill out the bottom end of the kick.
Dynamics processing can mould the recorded ambience by adjusting its decay characteristics. "Nine out of 10 times, the room sound will be compressed to some extent," says Joe Barresi. "Sometimes it may be severely compressed on what I call 'Full Canadian' setting, with all buttons pressed in and to the right. I like the EMI compressor for its fast attack. I often use the room mics for reverb, rather than adding reverb from a digital box."
The other time-honoured dynamics process here is gating, typically with the gate's side-chain keyed from one of the close-miked tracks in the arrangement. Few SOS readers will be unaware of the most famous example of this, created by Hugh Padgham for Phil Collins' 'In The Air Tonight', but this kind of processing can be found on many other albums in a less upfront role. Bill Price used the drum close mics to key different sets of ambience mics for the Sex Pistols' Never Mind The Bollocks, for instance, while the amplified synths on Depeche Mode's Some Great Reward were treated in similar ways by their engineer Gareth Jones: "I was enjoying how omni mics and boundary-layer mics captured the rooms, and that was so much a part of moving on from the '80s gated snare to having ambiences layered onto all the synths... There were also lots of gates, of course, because we were obsessed with getting rid of tape hiss, as well as closing down the rooms, even if they weren't gated abruptly along the lines of that classic gated reverb sound. All of the ambiences were tailored, so when the instruments or vocals stopped, the ambience would have a controlled shut-down."
If you're still reluctant to try using real room sounds on your own recordings because you feel that your acoustics aren't up to scratch, bear in mind Jack Douglas' insistence that this is actually a good reason to go for it. "Try to find some kind of analogue reverb in your house. Just the characteristics of that will make it stand out in your mix, simply because it's not going to sound like anything else... If you go down to your garage and you set up in a corner that has cement walls, there's going to be a very interesting standing wave there. Any place that has a strange standing wave is a good place to do a vocal, because it has such a different sound."
This great book of interviews is, in my opinion, one of only a handful of truly essential record-production books, and is packed with down-to-earth recording advice as well as discussions of the art of production. In addition to the interviews I've referred to in this article, the book also features such greats as Brian Wilson, George Martin, and Geoff Emerick, and one of the strengths of Massey's approach is that he often asks them similar questions, which makes for interesting comparisons. There are also two interesting panel discussions where several of the featured producers discuss their trade head to head.
£ Behind The Glass by Howard Massey (ISBN 0879306149), £16.95.
Before we leave the idea of recorded reverb to look more closely at mix-room tricks, it's as well to touch on one other fairly common situation where reverb is captured during tracking, and that's when a unique reverb device is vital to the sound of the track, but may be unavailable to the mix engineer. Analogue reverb devices such as chambers, plates and springs are all frequently recorded by the pros for exactly this reason. Our recent interview with Tom Elmhirst about his mixing for Amy Winehouse gives a good practical demonstration: Mark Ronson's recordings of different collectable springs and plates during tracking on both sides of the Atlantic gave Elmhirst a range of retro reverb sounds to supplement his own in-house effects options.
A tricky situation arises, though, when an instrument's built-in spring reverb turns out to be an indispensable ingredient of the sound, and it's not possible to record the spring separately. While Jim Abbiss used compression to pull up the tail of an undercooked recorded spring reverb while recording guitars for The Arctic Monkeys, dealing with too much printed reverb of any kind is usually nigh on impossible.
Fortunately, though, there's an ingenious workaround, which Ken Nelson used to great effect while recording Coldplay's guitarist Johnny Buckland: "Johnny has a Fender Twin Reverb, and he has all these [effects] going into it... I was thinking 'How am I going to get around that?' I just wanted to have the option of a bit more dryness. They had another Twin Reverb, a slightly different version, and I said 'What would be great would be if you could use both amps, one having all your [effects] going into it, and one that's completely dry.' All his effected sounds would come out of one amp, so we'd mic that up, and mic the dry one as well, so every time, we'd record both amps. I think that worked really well — both were used in the mix, and we just balanced it."
Although most SOS readers associate capturing real reverb with the tracking stage, in reality a surprising number of high-profile practitioners continue to reap the benefits of this kind of organic ambience by miking up rooms and then sending sounds from the mixer to them via some kind of loudspeaker. "I like to use the [live] rooms while I'm mixing," says S Husky Hoskulds. "I'll usually have two small PAs going and usually a couple of speakers as well, so I often have all three rooms at the [studio] miked up. All that stuff will come back into the mix through a small submixer at the side of the main console so I have a choice of different sounds: [a stereo mic] in the main room, or a couple of close mics, or a couple of stranger mics on another PA in another room... People will ask me how I get my room sound, and the simple answer is: by using the room! There's a lot more character to real rooms, and they don't have that flag on them that shouts 'Reverb!'. Room sound has dimension to it, because a real room has real dimensions."
Tony Visconti used room sound at the mix when working on David Bowie's Reality, to recreate some of the ambient sound from the artist's previous album, recorded at a different studio: "We put the monitors exactly where we'd put the drum kit two years ago and we pointed them slightly upwards at a 45-degree angle so that they were shooting upwards and outwards. We also had a pair of Earthworks mics hanging from the rafters, about 25 feet above the monitors, which is exactly where they were above Matt Chamberlain's drum kit during the Heathen sessions. We put them through the same preamp and the sound was there automatically. We then recorded this on a pair of tracks in Logic and brought it back to Looking Glass [Studios] to use in the mix. The result is that there might be a slight difference, but overall it sounds as if the drum kit was [in that room]... It's got a nice one-second decay in there, which is ideal for drums."
For engineers who regularly mix using real room sounds (people like Bob Clearmountain, Jason Corsaro, Simon Dawson and John Fry) it clearly makes sense to set up dedicated reverb chambers, thereby saving on setup time and allowing them to tweak the acoustic characteristics of the sound without endlessly moving soft furnishings around their recording spaces! Of course, this is exactly what the top recording studios did before the advent of decent artificial reverb devices, and some of the most celebrated studio reverb chambers still draw the punters to these establishments even today.
All the same techniques that producers use while tracking to tailor the sound of ambience mics are equally applicable in the context of chamber reverb. John Fry, for example, talks about shortening the reverb time of one of his reverb chambers with rolls of fibreglass, while Tony Platt gated the sound of the massive recording room at Galaxy Studios to alter its apparent size for different tracks when working with industrial band Die Krupps. While there are those who argue that convolution processing can now perfectly replicate chamber sounds, reproducing these kinds of real-world tactics is a lot more complex, so I don't expect the concept of using PAs and mics at mixdown to start pushing up the daisies for a good few years yet.