Tony Rigg's control area before the Studio SOS, with reflective walls and no acoustic treatment.
The SOS team are confronted by a confusion of speakers this month, and opt for a cost‑effective DIY approach to sorting out Tony Rigg's studio acoustics.
Tony Rigg has had more than the usual share of success with his music, and has integrated an impressive number of classic 1980s keyboard instruments into his Cubase 4 setup, but having moved to a new house he found himself in an untreated room, unsure as to the best way to approach acoustic treatment.
While needing the room to sound good for monitoring, Tony always wanted the acoustic to be lively enough to record acoustic guitars and other instruments. His studio room is a little under 2.5m high, around 3m wide and 5m long, and he'd already set up his gear with the monitors firing down the length of the room towards the bay window at the far end. The bay window had been fitted with slatted blinds which, when set at 45 degrees, helped scatter the sound.
Diagnostics
Our solution was to put DIY broadband absorbers in place at the mirror points (to the left and right of, and above the listening position).
The first thing we noticed on entering the room was that Tony had six (yes, six!) different sets of monitors, with provision to switch between them. Although there are sometimes good reasons to have more than one set of speakers, having that many makes it virtually impossible to get them all in the right position, and it can cause other problems too — which will be discussed later...
Three of the four walls were of plasterboard‑on‑timber construction, with smooth, plastered, painted surfaces throughout. In combination with a laminate floor, this produced a predictably lively sound that was too reflective for accurate monitoring. One up‑side of the construction was that the plasterboard walls would provide some natural bass‑trapping; the room would almost certainly have sounded quite different if all of the walls had been made of solid brick or concrete. Also, because the room was reasonably long, we reckoned that we could leave the back part of it untreated to get a nice live sound, but still have a well‑controlled area in the monitoring position.
You've Been Framed!
Rather than use only acoustic foam, we'd suggested to Tony that we make up some acoustic panels using mineral-wool slabs, fixed into wooden frames and covered with fabric. Our initial suggestion was that we use a four‑inch deep (100mm) frame to leave an air gap behind the 30mm high‑density mineral-wool slab we'd be using (1200 x 600mm in packs of five from Wickes), and to employ cheap black weed‑screening garden fabric to cover the backs, so as to prevent any mineral-wool fibres escaping. (This weed‑screening material seems to sit somewhere between fabric and paper, rather like some disposable cleaning cloths.) The fronts could then be covered with any porous fabric with the required colour and finish, such as cotton bedsheet or more exotic furnishing fabrics.
We arrived to find that Tony had already made up some wooden frames that were essentially the same depth as the mineral‑wool slabs, and he'd also bought a large roll of weed fabric, but he had no additional covering for the fronts, because he thought the weed fabric would look OK. As it was all we had, we tried covering one panel to see what it would be like — and it turned out that as well as being suitably porous, the fabric looked surprisingly good for the panel fronts. However, it isn't as strong as normal woven fabric, so it tears and snags easily, which mean it wouldn't really be suitable for high‑traffic areas. In this room, though, the panels would be fixed to the walls behind the keyboard racks, so they should be largely out of harm's way.
The main problem we faced was that as Tony had made the frames so shallow, we wouldn't have an air gap behind the frames unless we used spacers to mount them above the wall, which we decided to do. Once we'd built and covered the frames we screwed two wooden battens across the back, which would double as spacers and hanging points.
To assemble the frames, we first pushed each slab into its frame, then stapled fabric over what would become the back of the panel, trimming it to size after fixing using a Stanley knife. With that in place, we covered the front, folding the fabric around the frame and stapling it on the back, stretching it slightly and evenly as we went, to avoid wrinkling. With most DIY staplers, whether manual or electric, the staples rarely go into the wood as far as they should, and so we went around with a hammer to tap all the staples firmly into place. All that remained then was to dust off any mineral-wool fragments and sawdust that the fabric had picked up. If you're planning to do this yourself, a sticky pet-hair roller would probably be more effective for this job.
Hugh and Paul used 30mm‑thick mineral-wool insulation slabs to create the broadband absorbers, and these are available from most large DIY stores.
In all, we made up five panels, with a view to putting two on each side wall (to cover the first-reflection mirror points), and one on the ceiling, to cut down reflections from that quarter. The panels hung on the wall were each put up 'picture style', suspended on a single screw to minimise damage to the walls. For the ceiling, we used metal plasterboard fixings, of the type that screw directly into the plasterboard using a very coarse thread. Ordinary brass hooks were then screwed into the fittings, on which we hung loops of nylon line that we fixed to the cross battens on the back of the panel. This worked beautifully, leaving the panel hanging parallel to the ceiling, and suspended around 50mm below it.
A pair of 600 x 600mm foam panels (courtesy of Universal Acoustics) were fixed behind the monitors, again using wooden spacers glued behind them, just to leave a 20mm air gap and to provide a hanging point so we could use single woodscrews. These were mainly intended to reduce any mid-/high‑frequency reflections from the large area of blank front wall.
After placing a slab in a wooden frame, Paul staples some lightweight weed‑matting in place to secure any stray mineral‑wool fibres.Listening tests confirmed that the sound was now much drier at the listening position, with predictably better stereo imaging. We'd also been lucky with the low end, because there were no obvious hot spots, largely thanks to the room's large size and construction, and the location of the monitoring position within the room (well away from the centre).
Monitor Mayhem
Finally, wooden battens were screwed to the panels to space them from the walls and allow them to be hung .
Tony's setup had all his speakers facing directly forward, but what was really needed was to get them aimed at the listening position. As Hugh quickly discovered, the Mackie 824s in particular sounded noticeably dull, and he even checked the rear-panel switch positions to make sure the HF response hadn't been attenuated by accident. In fact, most of the speakers were being heard some way off‑axis, and although we couldn't do much about the large B&W or JBL speakers that were placed on the floor, we felt we could do better with the four sets of monitors that were at meter‑bridge height.
A pair of active Quested monitors was outermost, and we had to move some kit around to give us room to angle these inwards, which we achieved by putting the NS10s (the innermost pair of monitors, which were sitting on Auralex MoPads) vertically rather than horizontally. They are often seen on their sides in professional studios, but this is usually either because someone has seen others use them that way, or simply to maximise sightlines through the live-room window. Vertical mounting is better from a sonic point of view, as this gives a wider sweet spot and much less coloration.
A pair of Mackie HR824s positioned between the Questeds and NS10s was also angled inwards, so now all three pairs were aimed more or less in the right direction. The Mackies were set for 'half space' operation, with the low-frequency filter set to 47Hz. A small pair of KEF domestic hi-fi speakers were placed upside down on top of the Mackies, so their tweeters were at the bottom, closer to ear height (tweeters should be heard on axis, and placing them the other way up would mean they'd have to be mounted rather precariously!). Auralex foam wedges were placed beneath them to aim the tweeters at the listening position.
Hugh's stalwart BBC acoustics test CD helped us confirm that the sound was now much more focused, with a better high end, due to the tweeters now being aimed at the engineer's head, and the Mackies now sounded much more accurate and balanced. There was still a little low‑mid muddiness evident on some material, though, and we attributed this to the number of monitors in the room — because every unused pair essentially acted as a resonator, returning energy to the room; placing a finger lightly on their woofer cones revealed that they were all vibrating slightly in sympathy! Active speakers with the amp powered up are slightly less problematic in this respect than passive speakers, as the amp provides a bit of electrical damping, but the only way to improve on this for passive speakers is to arrange to short out the woofer when the speaker isn't being used — which isn't a trivial matter, and may only bring about a small improvement anyway.
Tony had six separate sets of speakers set up in his control room — but they were arranged in such a way that he couldn't get the best sound from any of them.In reality, the number of speakers Tony had in his room meant that he would have to live with the effects of these clouding the lower mids (which wasn't really too serious) or cut down on the number of speakers in the room. Although being able to check a mix on a variety of different speakers is useful, two or three pairs in one location are usually enough: typically an accurate pro monitor, a reasonable hi‑fi, and a 'grot box' such as a ghetto blaster. Really, any further additional monitoring should take place in different environments, as this will remove any room‑acoustics issues from the equation and enable you to check how well the mix 'travels': listening in other rooms, on other hi‑fis, and in cars or on portable systems would give a far more representative and balanced impression of the qualities of a mix than listening in the same room, in the same place, on six different systems all piled up next to each other. And Tony's current set up did look more like a Richer Sounds hi‑fi shop showroom than a well-sorted mix room!
Vocal Recording
The Studio SOS team focused on getting a few sets of speakers working well, angled in to fire at the listening position, and with the KEF hi‑fi speakers turned upside down so that the tweeters were level with Tony's ears.
Having sorted out the monitoring as well as we could, we turned our attention to the subject of vocal recording. Tony was using an SE Electronics Gemini mic while we were there, fitted to an SE Reflexion filter on an SE stand. Unfortunately, the Reflexion Filter had previously suffered some damage after his mic stand became unstable and toppled over, denting and bending the Filter and forcing a return visit to Neumann for one of Tony's expensive studio mics. We were able to partially disassemble the Reflexion Filter, straighten a few things out and rebuild it to restore the aesthetics and performance. Our standard SOS mounting arrangement (/sos/may09/articles/qa0509_2.htm) would provide a more stable configuration in future.
The recording end of the studio was left very live, as it seemed to work well for acoustic instruments, and there was sufficient length in the room that this didn't interfere with the acoustics at the listening position.However, we also felt that the recording quality could be further improved if some form of absorber were placed behind the singer. The reasoning behind this is that in a reflective room such as this, some of the vocal sound bounces around the room and ends up being reflected from the wall behind the singer, back into the hot side of the mic. Placing an absorber behind the singer reduces this quite considerably, and in conjunction with a Reflexion Filter, can produce better results than many vocal booths. A simple way to achieve this is to set up a boom mic stand in a T-shape, then drape a heavy polyester duvet over it, setting the stand height to centre the folded duvet behind the singer's head. Alternatively, you can hang panels of acoustic foam behind the singer, or use movable mineral-wool screens — but the duvet has the attraction of being simple, cheap and easy to store when not in use! It's also important to make sure that the mic isn't buried too far back into the Reflexion Filter: the mic's diaphragm should be roughly level with the front edges of the Filter. Pushing it further back will reduce some ambient pickup, but at the expense of a much more coloured sound.
Taking The Biscuit
Tony was pleased with the significant improvement in the listening conditions at his monitoring position, and was also relieved that he hadn't had to compromise the recording area at the back of the room to achieve this. He also took on board the duvet suggestion for vocal recording, and seemed very keen to get back to making some music. Finally, having inflicted some serious damage on his luxury biscuit selection, we set the SatNav for home and left him to it.
Reader Reaction
"Following some remote diagnostics over the phone, Paul and Hugh came in and had it figured out straight away. The very cost‑effective acoustic panels and additional foam on the walls completely changed the characteristics of half of the room, while still preserving ambience in the live section of the room. In fact, at this point I thought it was 'job done', because of the dramatic transformation!
"You see things done, such as Yamaha NS10's being placed on their sides, and assume it's the best way, but put in the upright position they sounded much tighter. A bit more tweaking of the other monitors and my confidence to mix in the space was restored.
"Since the alterations, I've put the setup through its paces and it's comparable to, if not better than, any decent compact pro studio I've been in. As I'm hearing my monitors more accurately, I spend less time switching between different speakers, and get the mix right quicker. I'm getting a great sound recording acoustic instruments with microphones too, and Paul's suggestion of placing a duvet behind vocalists is giving me great results.
"We have a purpose‑made studio with an amazing-sounding live room in which we track, but I think we'll be doing more and more in this home facility. I really feel that we can now go on from strength to strength. Even Pash (my very fussy Executive Producer) thought the improvement was amazing. Thanks to the Sound On Sound team: I'm over the moon with the result!”
Sending Out An SOS
Tony Rigg.Tony Rigg has worked in and around the music business for the last 20 years or so in a variety of different roles, including Operations Director at Ministry of Sound. As an artist, as well as a remixer for other labels, he has been featured on chart-topping albums, and has been a major player in the late‑night music entertainment industry. His latest venture is a musical enterprise called 'The Laboratory Project', which he describes as "a response to the homogeneous rubbish that we are force fed by the dominant institutions in the music industry”. He's interested in helping artists realise their full commercial and artistic potential, so if you make brilliant music in any genre, and would like to find out more, check out www.thelaboratoryproject.com or email info@thelaboratoryproject.com