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My requirements

Whether for fun or profit, turning that spare room into a workable recording space requires some forethought and a little knowledge of sound physics, along with time, patience and all the money you can possibly throw into the project. Such is the position in which I found myself a short while ago. I’d just become engaged to a great gal who owned a townhouse in a busy, crowded and noisy area of Los Angeles. Neither of us wanted to move, but I needed a place to work, and I didn’t want to pay rent for a commercial facility (been there, done that).

But a townhouse? Faced with a homeowner’s association code longer and more complex than the Geneva Convention, and various sets of elderly neighbors with remarkably keen hearing, the sensible alternative would have been to seek another option.

However, the sort of recording I had in mind—electronic music production, guitars through amp simulators, occasional live vocals, horns and drums—wouldn’t be impossible in a properly set-up small room. Having previously owned and operated a commercial studio in a business park, I was used to a certain quality level and had learned a few things about attracting and keeping clients as well.

I knew a home studio would involve some compromise, but there were a few key requirements. I wanted to be able to monitor at a reasonable volume, and to be able to work most days and a few nights and weekends. I wanted the best and most accurate monitoring environment I could afford, knowing that this is the primary factor in achieving mixes that compare favorably with today’s hit records. I wanted a sonic environment good enough that voices and instruments would sound great naturally, so that EQ and effects would be used as enhancements rather than salvage measures.

I also knew that the room would have to be kept cool and comfortable for clients in our hot California summers, a detail many home studios neglect or gloss over. Finally, I wanted the place to be reasonably organized and orderly, and to look good enough to bring in the occasional corporate client.

My laundry list of demands turned out to be a pretty tall order when I realized what we had to work with. Our best and most isolated site for this purpose was the garage, but it would require a fair amount of work. The first necessity would be to erect a wall separating the garage into two rooms: an exterior area for cars, and a framed, finished interior room that would become the studio. This room measures approximately 11 by 12 square feet with a seven-foot ceiling: clearly not a studio designer’s dream.

 

Wow, I never heard those trucks before…

One of the biggest pitfalls home studio builders encounter is underestimating the harsh realities of acoustic principles. The home environment, unfortunately, is not kind to the would-be sound recordist. Wallboard is often only 1/2″ thick, which does little to contain sound and will actually flex and vibrate with loud sounds, producing resonance. Room surfaces are also generally parallel, which will enhance resonance of certain frequencies at the expense of others. Wood floorboards transmit sound from one room to another whether or not this is desired. Ceilings easily transmit sound from the floor above. Windows, welcome for their light and views, allow sound in and out with frustrating ease, and provide the neighbors with a full view of your setup whenever the curtains are open. Finally, electrical power and lighting, often an afterthought, are frequently insufficient and too noisy for serious studio use.

Add to the mix possible noise from refrigerators, dishwashers, water pipes, pets, passing traffic, and it’s easy to see the problems plaguing the home recording environment, before you even worry about the neighbors. Unfortunately, the superb specs of today’s recording equipment virtually guarantee you’ll hear everything, too. The perils of progress….

Professional studios solve these problems in various ways, all of which cost money. The most common building scheme is to create a room within a room, isolating each from the other by means of insulating foam, soundproof materials and as much empty space as available real estate permits. (I’ve worked on TV sound stages where the distance from the outer to inner walls was nearly six feet.) Walls use double layers of 5/8″ wallboard and are typically lined with a barrier material such as lead or Auralex Sheetblok (more on this later). The wood floor is usually floated above the concrete sub-floor via heavy springs or rubber hockey-puck-like materials. Ceilings are high and sloping, separated from the walls and usually packed with insulating mineral fiber. Furthermore, wall treatments act to enhance sound in the room, not just contain it.

I knew I couldn’t afford all this in my humble facility, but there were actually a few pluses in my garage location. The floor was not wood, but sheet vinyl over bare concrete foundation. The walls were 5/8″ wallboard, and doubled on the side connecting with the neighbor’s unit. The ceiling featured a generous 10″ cavity between it and the floor above. It also did not “join” any other units in the building, and most likely nobody would be walking on the floor overhead during recording times. Also, a thick brick wall sat at the rear of the room, facing into the solid earth beneath our patio. Clearly, this older building had been designed with some idea of sound retention in mind, if for no other reason than just to prevent neighbors from killing each other. Things were looking up.

 

Beginning work

My first step was to contact two professionals: Bob Sagaert, the contractor who would do most of the heavy construction; and Rusty Sulzmann of Auralex Corporation, who would provide advice on soundproofing and acoustical treatment. (Note: this is a free service that Auralex provides, and you don’t have to be rich or famous to qualify—click here for details.) After hearing of my plans for a townhouse studio, both of them suggested I build elsewhere, and I suspect my sanity was questioned. Bob Sagaert reviewed the list of work, which would include:

a) Building a wall with a solid door, fitting it with Sheetblok and various light and electrical outlets, including remote headphone jacks.

b) Building a drywall “closet” around the water heater and soundproofing it adequately.

c) Providing adequate, silent overhead lighting and clean, grounded power for my equipment.

d) Perhaps the biggest challenge: provide an affordable air-conditioning system quiet enough to use during sessions.

His estimate for this work came to $5000, including the A/C and hardware. We agreed and the construction began in earnest.

The first step was to build the isolating wall. This was made with 5/8″ wallboard, stuffed with insulating foam and a layer of Auralex Sheetblok. Two four-way AC outlets were added to provide power for musicians and their toys, and 1/4″ headphone jacks were built into the wall for cue sends. These were wired with shielded cable, so they can be used in reverse as well to send signals into the console.

Sagaert added in two additional circuits on 20-amp breakers, as well as replacing some of the existing 14-gauge wire with 12-gauge. He also informed me of a new power trend for recording studios: balanced power systems in which a transformer provides plus and minus 60 volt lines referenced to a middle ground. Although it did not turn out to be necessary in my case given the relatively clean power here, it would have been a lifesaver at some of the industrial park locations I’ve worked in.

 

Light and air

Lighting was a special problem given the low ceiling. Track lighting was out of the question, as one of my clients is 6’7″ and can only fit here if he removes his cowboy boots. Fluorescents, while easy on the power bill, are always a studio no-no due to the inevitable hum, and anything halogen would likely be way too hot for this small area. Recessed ceiling cans seemed the way to go, but these would compromise the ceiling’s sonic integrity; furthermore, most types are designed primarily for new construction and will not work in a remodelling project.

After some searching, my fiancée found an online source for remodel-friendly ceiling cans, and three were mounted right into the ceiling, making maximum use of the available space. Insulating mineral fiber was packed around the canisters in order to lessen the obvious compromise in sound retention. (Note: not all canister lighting is insulation tolerant.) These have worked out well, although necessary spot lighting was added later. There’s something about a room covered in gray foam and black carpet that makes it difficult to illuminate!

Sagaert’s work with the air conditioner proved to be pure genius. He mounted a window unit in the garage exterior, above the car, suspended in a plywood frame. A customized ducting system leads to a vent in the ceiling; this is encased in plywood and packed with insulating foam to preserve cool air and prevent sound transmission. It’s virtually noiseless and provides a pleasant cool atmosphere for people and gear.

Sagaert’s work took roughly a week, during which time we tried our best to hide the project from curious neighbors. A word to the wise: any construction taking place in a townhouse complex is considered an open invitation for impromptu discussion. If someone does ask or decides to complain, please make sure ahead of time that you’re not violating any zoning laws, building codes, or housing development covenants with your building plans!

With the heavy construction finished, we moved on to the sound treatment phase.

 

Tuning the room

Rusty Sulzmann of Auralex recommended a variety of his company’s products to make the room work. During the construction process, we began with Sheetblok, a thick vinyl sheet which inhibits 6 dB more sound transmission than lead. This material is normally nailed onto wall framing and then covered with drywall or wallboard. We purchased two rolls of Sheetblok Plus, which features an adhesive backing to temporarily hold the product in place while fastening (a welcome innovation, believe me).

We also purchased a kit containing quite a number of 2″ Studiofoam panels. These are the corrugated foam wall treatments typically seen on studio or radio station walls. According to Sulzmann, we would need to treat roughly half the wall surface area with this product, with special consideration given to the mix position. Placement would not be critical, but no two non-treated wall surfaces should face each other. Corners, notorious for producing bass resonance, were treated with LENRD bass traps—thick, heavy corner foam pieces designed to eliminate bass buildup.

At the critical mix position, Sulzmann suggested placing nearfield monitors on isolating MoPADs to prevent them from vibrating everything underneath them; this inexpensive product makes a huge difference in getting accurate sound from a console- or table-top nearfield monitor system. (Nowadays I would give serious consideration to IsoAcoustics isolators, but they weren’t available when this project was going forward.) Behind the listener, plastic T’Fusor panels gently disperse sound waves (while giving the studio a cool Star Wars set look).

When the products first arrived, my first thought was that we’d bought enough foam to encase the entire building; this would prove to be wrong. Sulzmann’s estimate was pretty much on the money, and a few leftover pieces were easily resold to musician friends. It was a substantial investment, but I knew from prior experience that plain foam rubber, no matter how attractively cut and painted, did nothing to enhance sound, and cheap audio treatment foam had a tendency to decompose over several years, not to mention the potential fire hazard.

Mounting the Auralex foam products was relatively straightforward. For the most part, the material cuts easily with a razor blade knife. The company makes two different adhesive products, one permanent and one removable, for securing the foam pieces to the walls. We chose the latter (Foamtak) out of concern for possible permanent wall damage, and it’s held up well so far, even on the ceiling.

 

Installing gear and furniture

With the construction aspect finished, it was time to install the gear. I didn’t have a ton of stuff, just a modest operation built around a Mac running Logic and a Roland VS-1680 which was both mixing console and occasional field recorder. I had a small portable rack containing MIDI modules that accompanied me to outside sessions and gigs, as well as a large floor rack housing two HHB Radius 40 tube mic preamps, a Grace Design solid-state preamp and a TC Electronic M-One XL effects processor. I also had a custom-built studio console desk with a 20-space rack below containing a Panasonic SV-3700 DAT recorder, an 8×8 MIDI interface, a Sony CD recorder, a TASCAM cassette deck, an old BGW power amp for the nearfields, and various hard drives.

To this setup I made a few additions: two Furman RP-8D rack-mounted power conditioners, a Behringer headphone amp, and a Neutrik 1/4″ balanced patch bay. More would come later, of course, but I had enough to work with for now.

Wiring the entire thing together was difficult in the small space. I like neat cable-tied wiring, and I usually label every cable end; if a device has to be removed for service, it will be much easier to hook back up later if you know where everything goes. I generally choose medium- to high-price cables, but balk at paying top dollar for esoteric designer cables as I have not found their claims to be substantiated.

Two areas where quality is critical are mic cables and digital audio cables; skimp on these at your own peril. I can’t remember how many episodes of “gee, this mic suddenly sounds like crap,” or “hmm, there’s this strange digital noise and the signal suddenly drops out” have been fixed by a cable upgrade.

To the greatest extent possible, audio lines—especially unbalanced—should be run away from AC power, digital audio, and other computer cables. Try to separate noisy wall-wart transformers from audio lines as well. Also, it’s best to keep all cables as short as possible. Soldering your own harnesses to the exact needed length is a great option, but can force you into major rewiring projects for the slightest gear change. I elected to custom-solder a few critical harnesses, and just buy quality cables for the rest.

One thing that greatly reduces noise in electronic sound transmission is the use of balanced lines. Once unavailable except in the highest-end audio products, these days even budget-priced audio devices from keyboards to rack processors feature balanced connections, either on XLR jacks or 1/4″ three-conductor tip-ring-sleeve (TRS) jacks. With this in mind, I set up my patch bay running balanced lines wherever possible; this required some custom cable soldering.

I configured the patch bay in a half-normalled arrangement; this means that each jack on the upper row is normally connected to the one below it without any cable inserted. Inserting a cable in the lower jack breaks the connection, allowing you to change the default routing. I noted with some irritation that the normalling feature on this particular bay requires you to reverse the common studio practice of placing inputs on the top row and outputs on the bottom, but I’ve gotten used to it.

Mounting gear into racks takes a bit of forethought as well. Generally, you want anything you need to “tweak” on a regular basis to be up close to your working level. Also, give some consideration to which devices generate significant heat; you don’t want your 1800 watt subwoofer power amp cooking your delicate boutique mic preamp. For longer gear life and reliability, consider a rack fan if you have a lot of tube devices or power amps.

Grounding is another issue with rack gear. Very slight differences in chassis ground voltage have a way of becoming magnified through the audio chain, producing terrible hum. Pro studios often use a “star” grounding scheme in which a large steel spike is driven deep into the earth through the studio subfloor, and every device’s chassis is grounded to this by a wire of equal length, thereby insuring identical ground potential for everything in the studio.

Home studios can’t usually take such drastic measures. If you have a small amount of gear, simply placing everything on the same circuit may eliminate grounding problems. Usually, though, a single typical 15-amp home AC circuit is likely to be inadequate for studio needs. The breaker may not trip, but the line voltage can drop to the point where a $3000 tube EQ sounds like a toy, and the master keyboard changes patches for no particular reason.

In my case, I had to distribute gear over three different circuits. A few hums and buzzes cropped up, but I was able to eliminate them using nylon insulating washers which separate the gears’ chassis from physical contact with the rack rails. This is one of the cheapest hum fixes available!

 

Evaluation and last minute changes

At the time I finished the studio, I had been working on a huge corporate project out of my apartment. I had hoped to get the whole studio wired and running within a couple of days, and allow another few days for “test recording” before digging into client projects. Instead, I found myself facing the mixed blessing of having to get back to work before the project was 100% complete. I’d wanted to cover the side wall facing the neighbor’s unit with Sheetblok and additional wallboard. To this day, this remains half finished—but sound transmission appears minimal and the neighbors claim they don’t hear much (whew!). The heavy curtain I’d wanted to hang in front of the laundry machines remains unhung. The ugly ceiling pipes remain unpainted. Life, and studio work, goes on.

Nevertheless, a few things had to be addressed in short order. I was satisfied, but not blown away, by the sound at the mix position. There were no ringing resonances or peculiar peaks, but the mix sounded a bit lifeless and thin, as though the sound had come out of the monitors and just dropped dead directly in front. I reassessed my work: had I gone overboard with room treatment? Were my monitors (Event 20/20) not up to snuff? These were speakers I’d chosen for their ability to sound flat and even at a variety of monitoring levels, but they seemed to be letting me down.

I had a gut feeling that the monitors, which were sitting on speaker stands behind the console, were simply too far away to be effective nearfields. I took an afternoon, made a trip to Home Depot and spent some time making a shelf over the console to hold the audio and video monitors. Bingo. My monitoring environment improved miraculously, and I can now mix with confidence.

Of course, this improvement in listening environment brought about new gear lust. I was basically happy with my audio chain, but I longed for one really high-end, solid-state “clean” mic preamp. After some research, I ended up with a Focusrite ISA 430, which has really raised the quality level of my work.

Shortly thereafter, I began to wonder if my audio hardware was up to snuff, and whether some top-flight converters might be worth the considerable price tag. I ended up replacing the computer with a new Mac, using the RME Hammerfall HDSP 192 PCI audio card. This enabled me to have an entirely balanced recording chain, with a significant improvement in sound quality and reliability over the old hardware.

 

Final assessments

Building a professional quality project studio in the basement of a townhouse may seem like a nutty idea, but I believe for the most part I’ve succeeded. Isolation from outside street sounds is excellent. The air conditioning system works beautifully. The monitoring environment is flat enough to make sensible mix decisions. The room sounds great for light drums, solo or group vocals, acoustic guitar and horns. The wiring is neat and orderly, and patching is a breeze. It’s comfortable enough for clients to hang out, and has a fairly professional look—once you overlook the laundry machines, anyway.

Of course, there is always room for improvement. The small size of the room has imposed some difficult constraints. I can adequately fit a live drum kit in the room, but the mix position behind the console is small—hard for a client to squeeze in to hear the mix. I plan to add a set of auxiliary, wall-mounted monitors for this purpose. Also, I sometimes record my own acoustic guitar tracks, but to do so away from the desk and its nasty early reflections, I have to hire a Mac “tape op” for the session.

A recent critical corporate voiceover session brought up another surprise. I’d put all this work into soundproofing from the outside world—but the new Mac’s fan noise bled into the mics. I was able to deal with it by placing a heavy blanket over the console desk, but I think eventually the Mac is going to have to be relocated or somehow silenced. A completely “dead” isolation booth is another possibility in the works.

Good music comes out of surprising places these days. As the technology grows more affordable and compact, more musicians will be recording in unusual places. A little research, knowledge and hard work may just enable you to build your dream studio somewhere you wouldn’t have thought possible.

 

Do try this at home…

If you’re a musician intent on building a studio in a less-than-ideal space, here are a few suggestions to consider before you break ground:

1.) Define your recording goals. What do you want your studio to do? If you mainly remix or master previously recorded material, you may not have to worry too much about soundproofing. If you would like to record bands and live drums, you’ll need adequate soundproofing to make sure your neighbors don’t hear it. If you plan on recording dialog, or string quartets, you’ll need to worry more about sound coming in than going out. Hopefully, you’re not next to the train tracks. Remember that nearly any situation can be fixed, but it may not be worth spending $12,000 to float the floor if you only plan on recording a live drum track twice a year.

2.) Assess the suitability of your workspace. Is it at least reasonably quiet before you begin working on it? Are the walls (hopefully) different lengths? Is it unbearably hot, even with no gear adding to the thermal picture? If paying clients are part of the picture, will they be comfortable hanging out there for long periods of time? Are your neighbors the type who are likely to complain about your venture in spite of adequate soundproofing?

3.) Work out a budget. Prioritize things you will absolutely need to do (cover windows, perhaps) and be prepared to sacrifice a few of the less important items if costs become prohibitive.

4.) Plan for growth and change. Recognize that as cool as your place will be, you’ll want to make changes to keep up with technology, and also to address any needs that won’t become apparent until you’ve been up and running for a while. Maybe you’ll get some corporate A/V projects, and you’ll want to add a clock generator and appropriate video sync gear and video display screens. Maybe you’ll get into orchestral composing, and will want to add a second audio computer running some huge sample libraries.

5.) Learn all you can. The science of acoustics is complicated and involves some scary math, but you can learn the basics in a variety of places. Even if you don’t plan on doing any of the work yourself, knowing a bit about what goes into making a studio will ease some of your anxieties and help you make wise decisions in the creation of your ideal recording space.

 

Bob Emmet is a recording engineer working in Los Angeles. Thanks again to Bob Sagaert and Rusty Sulzmann.

Acoustics and Monitoring