Building an Analog Recording Studio
by Fenris Wulf, KDVS Studio Tech
Making a living as an audio engineer is difficult, unless you're very skilled or very lucky. The vast majority of "recording school" graduates will never find a job in the music industry. (Making a living as a musician is even harder.)
In the old days, an audio engineer was actually an engineer: he had a degree in electrical engineering and was expected to design and build the studio's equipment from scratch. An engineer will always be in demand; if not in music, then in some other field. A person who only knows how to use the equipment is a consumer, not an engineer.
There is already an oversupply of digital studios and DAW jockeys, and few of them make any money. Record sales are at an all-time low, and DAW technology is partly to blame. Over-processed, over-compressed, quantized, auto-tuned records are not enjoyable to listen to.
If you're going to build a recording studio, build it around analog equipment. Instead of disposable computer equipment, you'll have equipment that was designed to last for decades. If you choose it carefully, it will be more reliable and trouble-free than any computer system.
I used various DAW's for ten years. When I moved to analog recording, I discovered that I could work about three times as fast. Every function has its own fader, knob, button, or meter. I can easily and quickly get sounds that are impossible to get with plug-ins. I can monitor off tape during recording and build the mix while I track. Our tape machine punches in better than a DAW and locates nearly as fast (it doesn't have to pre-load audio files or calculate delay compensation). I've re-used reels of tape dozens of times and never had a single drop-out. Most of the purported advantages of DAW's turned out to be illusory. (I only use a DAW for the occasional band that simply can't play their instruments or sing in tune without computer editing.) I did my research first and chose equipment that was well-designed from the standpoint of sound, functionality, and maitenance.
An analog studio doesn't provide unlimited tracks or micro-editing. You have to use fewer mics, simplify arrangements, make decisions in tracking, and get focused performances out of the musicians. This is a good thing. The faster you work, the better the end result will be. KDVS hosts weekly live-in-the-studio performances, with minimal setup time, mixed live to stereo, and the result is often better than the band's album (especially if it was recorded at a typical DAW-based studio).
Analog tape machines and analog consoles are severely undervalued on the used market. Thanks to Internet forums, you can find detailed information about specific models, how to maintain them, and what problems to expect. Older audio engineers are very generous about sharing their knowledge. The most common repairs involve cleaning switches and pots and replacing electrolytic capacitors, which you can do yourself. A number of companies specialize in refurbishing old tape machines and consoles.
When selecting equipment, you have to know something about circuit design, how various designs perform in real-world use, and how all the equipment works together as a system. "Using your ears" isn't enough, if you don't understand what you're hearing.
One sign of bad-sounding equipment is suspiciously good specs. Phenomenally low noise and distortion can indicate misuse of negative feedback. Nearly all circuits use negative feedback to improve linearity and stability; but when it's used improperly, it causes phase shift, ringing, and hard clipping. All circuit designs are a trade-off between different parameters: optimizing one parameter at the expense of others leads to a bad sound.
Modern equipment uses IC's, or integrated circuits, which is an entire circuit on a microchip containing dozens of tiny transistors. IC's allow complex circuits that would be impractical otherwise, but they dissipate less heat and have less headroom as a result. Some equipment uses surface-mount technology (ultra-miniaturized components that are heat-welded to the circuit board), which also dissipates less heat and is difficult to repair or modify.
Vintage equipment is discrete. Instead of microchips, it uses individual capacitors, inductors, resistors, and tubes or transistors. It uses simple circuits with a smaller number of components. It uses either point-to-point wiring, or roomy circuit boards with large traces. It's easy to repair or modify. It uses little or no negative feedback. Instead of being electronically balanced with IC's, it uses high-quality transformers, which have superior headroom and hum rejection (but are more sensitive to loading).
IC-based equipment can sound good, if it's well-designed and runs on a higher DC voltage. A good IC design tends to be clean and clinical, while a good discrete design tends to be euphonic and flattering. Some equipment uses a mixture of IC's and discrete components. (Some cheap equipment adds a tube or transformer for "color," but runs the tube at a low voltage and uses low-quality components. It doesn't sound "vintage," it just sounds fuzzy.)
Analog tape gradually saturates as you turn up the recording level. This creates soft compression, peak limiting, low-order harmonic distortion, and attenuation of high frequencies. It acts like a very complex frequency-dependent compressor with instantaneous attack and release. It smooths out the midrange bumps and exaggerated transients that result from modern close-micing techniques. Some of the peak limiting is inaudible by itself, but affects the behavior of downstream compressors and EQ's. It requires less processing in the mix and makes it much easier to get a good sound. Tape is especially useful for recording drums; the level and tone become more consistent and you don't have to spend hours triggering drum samples.
The "sound" of tape is related to tape formulation, tape speed, and recording level. By controlling these factors, you can go from a very saturated sound to a very clean sound. You can record everything from punk rock to classical music. (Digital has only one sound, and studios resort to buying multiple "flavors" of mic preamps to compensate for it.)
A good tape machine can do "clean" better than digital. It's more present without being harsh. Low-level details are more audible and the sound has more depth, contrary to the claim that digital has "superior ambience retrieval."
There is no substitute for a good multi-track tape machine. You won't get the same benefits by mixing to tape or by processing individual tracks from a DAW. Tubes and transformers don't saturate in the same way, and "tape simulator" plug-ins don't even come close.
Tape machines haven't been made in over 20 years, so you'll have to buy a used one. The seller should provide a head report from a JRF Magnetics; make sure the head life is 70% or higher, because replacement heads cost more than the machine itself. You'll have to learn how to calibrate the tape machine using an MRL tape, and how to get the desired amount of tape compression without clipping the electronics. (You don't do it by overdriving the input and pegging the meters.)
The output level of different tape formulations is specified in nanowebers per meter, or as a certain number of decibels over 185 nWb/m. Higher numbers indicate more headroom and less compression.
If you want audible compression, choose a lower-output tape. Calibrate the machine normally, then turn up the record level pot a few dB and turn down the reproduce level pot by the same amount. Use a sine wave generator to determine how much level your machine can handle without clipping; the weakest link is usually the record amplifier that feeds the record head. When you record, remember that -3 or -6 on the meters is actually 0. Tape compression can't be undone; you might decide that you prefer a high-output tape that preserves more of the transients and dynamic range.
Studer machines have the best transport, but Ampex, 3M, and Scully have the best sound. MCI is generally the easiest to repair and find parts for, but some older models have problems with bad chip sockets or bad solder joints. Otari and Tascam have a reputation for mediocre sound, but some models are quite good.
Older machines might have problems with incomplete erasure or tape wear when used with high-output tape formulations, but can be modified to fix these problems. Old AC-motor transports have more wow and flutter and rougher tape handling than modern DC-motor transports.
A wide-trackwidth machine (1" 8-track or 2" 16-track) has better low end and less hiss than a machine with narrower tracks. (Noise reduction degrades the sound and doesn't allow tape compression.) Modern tape machines (circa 1980 or later) have gapless punch-in circuitry, which makes it easy to fix mistakes; but vintage tape machines have discrete transformer-coupled electronics and better sound. A few machines have both, but they're hard to find.
(For the amateur recordist, a 4-track cassette recorder with varispeed provides endless possibilities for sound manipulation, and a 1/4" 8-track can be surprisingly hi-fi, if you don't mind a little crosstalk between tracks. These formats require noise reduction, which is usually built-in. They use a single head for play and record, and are pre-calibrated for one kind of tape.)
You can do almost anything on tape if you know how. Analog engineers used to trigger drum samples by flipping the tape over and duplicating the source tracks "early," playing the tape normally and dialing in the right amount of delay to eliminate flamming, recording the samples to an open track, and punching in to fix mis-triggers. This method is actually faster than a DAW.
There are a number of options for tape. ATR makes excellent tape, but it's a high-output formulation that doesn't compress very much. RMG offers two formulations, but some users have reported quality control problems. Quantegy is no longer in production, but a few varieties are still available for purchase.
You can buy used tape (it doesn't wear out quickly unless it's been abused), but you have to know what formulations and what years to avoid. Some tapes from the '70's and '80's have "sticky shed syndrome," in which the binder absorbs water from the air and becomes sticky and unplayable. About one-third of the used tape being sold on Ebay has this problem.
If you have to play back an old tape with "sticky shed," you can bake it in a low-temperature convection oven and it will be playable for a few weeks. Baking has no effect on the sound. Analog tape is still the only reliable long-term archival format. Many old digital tapes (DASH, DAT and ADAT) can no longer be played, because they use metal tapes that oxidize over time, and the slightest deterioration can overwhelm the machine's error correction. Optical discs (CD-R, DVD-R, and Blu-Ray) are also prone to oxidation, and hard drives can develop data corruption or mechanical failures. Data recovery services are incredibly expensive and don't always work. The only long-term solution is to back up your files on multiple formats and make new copies every few years.
There is nothing like a large-format analog console with high-quality electronics and motorized fader automation. You can work incredibly fast and do things that are impossible on a lesser system. But the cost of electricity alone makes these consoles impractical, unless your studio is very busy. A medium-sized console with 24 or 32 channels is sufficient for smaller studios.
Some used consoles are a bargain, but they might need extensive repair. You can save thousands of dollars by doing the repairs yourself. You can research specific models on Internet forums, learn how to repair them, and learn which ones aren't worth repairing or use hard-to-find components.
You should look at recording consoles, live sound consoles, and broadcast consoles, and find one that can be adapted to your studio's requirements. Transformers on the microphone inputs are a big plus. Good-sounding preamps and EQ's will save you a lot of money on outboard gear. Multi-pin connectors instead of XLR's will save time and money when you wire up your patchbay.
Professional consoles are modular: individual channels can be pulled out of the frame for servicing, and you can buy spares for every part of the console including the power supply. Semi-professional consoles are built on a single circuit board, use lesser-quality components, and have a lot of design compromises; they should be avoided unless your budget is less than $1000.
Analog compressors and EQ's remain popular, because even the digital mavens realize they offer something that plug-ins don't.
There are many companies making analog outboard gear, ranging from all-tube and all-discrete to IC-based designs. Some of it is very good. But you have to do extensive research to separate the good equipment from the junk. You have to talk to "old guys" who have been around long enough to know the difference. Don't believe anything you read in a magazine review or celebrity endorsement.
Vintage outboard gear has more maintenance issues and is often overpriced. Even the most obscure models have been "discovered" by Internet forums and driven up in price. The best modern designs are equal or better in sound quality.
Another option is to build it yourself. Several companies make pre-printed circuit boards for vintage-style compressors, EQ's, and preamps, complete with schematics and a parts list. They can be assembled by anyone with basic electronics skills, although it is advisable to start with something easier like a stomp box. You can choose different components and build something unique. There is a large online DIY community to help you out.
Analog effects offer hands-on control and endless sonic possibilities, and they don't have to be expensive. Echo can be created with a varispeed tape machine, a bucket-brigade delay, or an oilcan delay. Reverb can be created with a plate, a spring, or a chamber. Modulation effects can be created with a varispeed tape machine, a rotating speaker, a bucket-brigade chorus, a Hammond scanner vibrato, a Magnatone tube vibrato, or a Cooper Time Cube acoustic delay.
When it comes to digital effects (reverb, delay, chorus, or pitch shifting), vintage units with primitive converters and limited bandwidth are often better. They sound less like a clone of the source and take up less room in the mix.
PUTTING THE DAW IN ITS PLACE
If you have to do extensive editing, you can use a DAW in between the tape machine and the console. It should have at least 16 inputs and 16 outputs. Keep it as basic as possible, and you'll have less computer problems. The cheapest software running on a 5-year-old computer can do most editing tasks, unless you really need the latest quantizing and pitch-correction tools so you can spend all your time fixing bad performances.
Digital converter technology has not fundamentally advanced in the past 10 years. (Some would say 30 years; some of the early digital converters used high-quality transformer-coupled circuitry and sounded better than the average modern converter.) Don't spend all your money on audiophile converters, just to obtain a marginal improvement in sound for mediocre bands.
At higher sample rates, the anti-aliasing filter is less steep and filter artifacts are shifted above the audible range. But higher sample rates are inherently less accurate (more quantization noise and jitter). A sample rate of 96 kHz is the best compromise. (The frequency response is one-half the sample rate.)
There's a lot of debate over the audibility of ultrasonic frequencies. Pure tones above 20 kHz are not audible by themselves; but in combination with other tones, they produce intermodulation distortion in analog equipment (and in the human ear canal) below 20 kHz, which contributes to the perceived brightness of the sound. This is a good reason to use a 96 kHz sample rate.
DSD is advertised as having frequency response to 100 kHz. This is misleading. DSD is a very "dirty" method of conversion that uses noise shaping to shift all the noise into the ultrasonic range. This can degrade the performance of downstream analog circuitry. Filtering the noise limits the frequency response to around 25 kHz. Some DSD users report that it has a very pleasing and transparent sound; this may be related to the circuit design of specific DSD converters.
Always record to analog tape first. By reducing dynamic range, transient peaks, and extreme high and low frequencies, it reduces the audibility of quantization noise, ringing, and aliasing in the digital converter. If you run out of tracks, you can record overdubs through the tape machine into the DAW, using the DAW's "record latency" setting to compensate for the delay between the record head and the play head. (One company sells a special $7000 interface/controller that integrates any DAW with a tape machine, but it's completely unnecessary for most studios.) If your clients can't afford the cost of tape, you can use the DAW for archiving and re-use the tape several times.
The DAW can take care of mutes, pre-compressor gain riding, and other automation tasks. You can simplify mix recalls by using the "stem" method. Use the console groups to create submixes for vocals, drums, and instruments, and record the submixes alongside the main mix into the DAW. If the console has post-fader direct outputs, you can record individual channels complete with compression and EQ. Add the submixes into the main mix to make something louder; reverse the polarity to make it softer. Or you can do full mix recalls by documenting all the console and outboard settings with a digital camera.
Using a DAW is always a compromise. Mixing directly from analog tape onto a good 1/2" 2-track machine still sounds better, and some engineers edit the tape with a razor blade and splicing block.
To enjoy the benefits of analog technology, you need commitment and determination. You'll be using equipment and methods that most of the industry abandoned decades ago. There are no off-the-shelf or turnkey solutions. You'll spend hundreds of hours researching, refurbishing, and wiring up your equipment. Analog isn't for sissies!