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A.2. Designing a studio with proper acoustics

The first and largest component of the ultimate web sound studio is the room itself. A proper recording environment with pleasing acoustics and no echo or noise is essential to high-quality recording. (For more information about optimum room acoustics, see Chapter 3, "Capturing Original Source Material".) Successfully building a great sound studio depends largely on having the proper budget to design and remodel a room from scratch or the ingenuity to repurpose an existing room on a budget.

Pro option

Money and space permitting, most professional recording studios are customized from the ground up to have the ideal acoustics and optimum recording functionality. Professional studios generally have a minimum of two rooms: a control room for mixing and monitoring and a soundproof recording room for capturing the audio signal. The control room is where the audio engineer resides during a recording or mix-down session and contains mixing boards, a digital audio workstation, studio reference monitors, and so on. The recording room is where the musicians, voice-over artists, and microphones reside. Generally, the control room is directly adjacent to the recording room with a soundproof window built in-between so the engineer can supervise microphone placement and communicate with the recording artists.

Professional studios optimize good room acoustics by placing high-frequency-absorbing audio-grade foam on the walls and ceilings, bass baffles and traps on the floors and corners, and reflective hardwood floors for warmth and pleasing reverberation.

Budget option

Building a sound studio on a shoestring budget takes ingenuity and resourcefulness. Most web professionals and audio enthusiasts will have neither the luxury of building a room from the ground up nor an extensive budget to equip it with acoustic foam, bass traps, or sound isolation booths. For people with a limited budget, converting an existing square or rectangular room in their home or production offices into a dedicated sound studio is their only option. If you have one room for recording, mixing, and monitoring, the first step is to isolate and place any noisy, fan-cooled hard drives or power amps into a padded box or a closet with enough air circulation around the components.

Once you reduce any extraneous noise that can leak into your microphones during recording, place bookshelves, file cabinets, wall hangings, or other large objects against the walls to reduce echo and slap-back. If the ceiling and floor are parallel, place a rug on the floor or a tapestry on the ceiling to further reduce slap-back and echo.

A note about prices

Prices are current as of June 2000. While the prices listed in this appendix will change over time, the pricing information is included to provide you with an overall picture of the general retail markup of each make and model.

A.2.1. Microphones

Microphones capture and convert sound waves into electrical impulses. A good microphone is one of the first components you will need if you plan on recording voice-overs or live music. You will want to choose a microphone that has an extended high-frequency response and a low signal-to-noise ratio. A high-quality microphone should capture the entire audio spectrum of the human hearing range from 20 Hz to 20 kHz with a low 11dB of self noise. Inexpensive microphones generally only capture the frequencies between 50 Hz to 15 kHz and add a lot of noise into the audio signal.

A.2.1.1. Pro option

Generally speaking, the more expensive the microphone, the more accurately it reproduces sound waves and the more features it contains. A large diaphragm condenser microphone with at least two or three polar patterns, preferably omni and cardioid, is the industry standard for recording voice-overs and acoustic instruments. As far as all-around performance, reliability, and sound, there are several good condenser microphone options available in the $700 to $1,300 range, including:

  • Rode NT2 large-diaphragm condenser mic* (list $749/street $595) * Best Buy

  • Audio-Technica AT4050 multipattern condenser mic (list $995/street $650)

  • AKG C3000B large-diaphragm (cardioid) mic (list $520/street $350)

  • CAD Equitek E200 condenser mic (list $749/street $550)

  • AKG Solid Tube large-diaphragm tube mic (list $1,195/street $999)

  • Neumann TLM 193 large-diaphragm mic (list $1,495/street $1,199)

  • Neumann TLM 103 large-diaphragm mic (list $995/street $900)

Professional versus consumer grade equipment

 

Bear in mind that professional gear, as the name implies, is designed for people who are making money from audio production. This means at minimum a studio with at least $20,000 to $50,000 worth of equipment. Professional gear is expensive for a reason -- it is generally not mass-produced and contains electrical components that have been handcrafted and oft-tested.

 

If you find an inexpensive piece of equipment that claims to do everything, the price is probably too good to be true. Most likely the manufacturer is cutting corners with low-grade electrical components or simply misleading the consumer. The recent trend in consumer-grade audio equipment is to pack every piece of gear with the most possible features -- compression, EQ, reverb, and so on. This often leads to more system noise and makes the piece of equipment more difficult to use when trying to get a quick task done under pressure.

 

Look for equipment that is known for doing one thing really well. You will find the audio quality is better, and the tool is easier to use.

A.2.1.3. Pro option

  • Electrovoice RE-20 large-diaphragm dynamic (standard radio announcer mic) (list $665/street $479)

  • Shure SM-7 Warm, big dynamic (list $450/street $349)

A.2.2. Mic pre-amps

A mic pre-amp boosts the weak output signal of a microphone, just as a telephoto lens magnifies the image of a regular camera lens. A good mic pre-amp is the most overlooked component in the recording studio. Novices and beginners alike usually find it easy to understand why a good microphone is necessary for high-quality recording, but few comprehend why mic pre-amps are just as important.

When it comes to choosing one or the other, the microphone always comes first. But a high-quality outboard mic pre-amp should always accompany your investment in a good condenser microphone. Without a mic pre-amp, you will not reap the full benefit of a professional-grade microphone.

A.2.2.1. Pro option

Most professional studios utilize separate, high-quality outboard mic pre-amps, or expensive mixing consoles, which have built-in high-quality mic pre-amps. These components start at $30,000.

The difference between a high-quality mic pre-amp and a poor-quality one is the output clarity and purity of an amplified low-level microphone input signal. A high-quality mic pre-amp magnifies every nuance and subtlety of a microphone signal without introducing noise. A cheap mic pre-amp, like the ones found in most 16-channel mixers, introduces system noise into the signal path and easily overloads and distorts loud input signals.

A few good mic pre-amps include:

  • A.R.T.-Pro MPA Stereo Tube mic pre-amp* (list $599/street $495) * Best Buy

  • Millennia Media HV3B Stereo solid state mic pre-amp (list $1,895/street $1,700)

  • Joe Meek mic pre-amp and compressor (list $600/street $450)

Additional resources

How to Build a Small Budget Recording Studio from Scratch, Second Edition by Frederick Alton Everest (Tab Books, 1998) is an excellent, practical handbook on acoustics that is suitable for both professional and beginning engineers.

A.2.3. Compressor/limiters

Acompressor, as the names implies, is used to even out and compress incoming audio signals that vary greatly in dynamic range. An example is a singer going from a soft whisper to a resounding scream. A compressor allows for the hottest incoming signal possible to your sound card without distorting it by limiting the sounds that peak above the 0dB-distortion range. By reducing the amplitude of the loudest sounds with a compressor you can increase the input level of your microphone to get a hotter recording. Compressors are used widely in pop music where the aesthetic dictates that the overall volume and presence of each instrument remain consistent throughout the mix. Compressors are not as ubiquitous in classical or jazz music, where a wider dynamic range is preferable. However, in the age of hard-disk recording, compressors have become a necessity to avoid digital distortion.

A.2.4. Digital audio workstation/recording editing software

The digital audio workstation is the centerpiece of the web sound studio. Audio workstations contain special DSP chips for audio processing and analog-to-digital conversion, as well as recording and editing software. Most sound cards have at minimum one pair of digital inputs and outputs as well as analog stereo inputs and outputs. More expensive systems have 8 to 16 direct inputs and outputs.

Low-end systems generally offer software-only solutions and rely on the internal DSP of your CPU to process audio. Along with a sound card, you will need a computer with a 2 GB or larger AV hard drive, 120 MHz CPU or faster, plenty of RAM, a 17-inch monitor, a proper universal power supply unit, and a backup storage system large enough to store the contents of your hard drive.

Note that a few packages listed in the budget option are two-track stereo editors designed for audio mastering, editing of final mixes, and two-track recordings.

A.2.4.2. Budget option

Low-end hardware/software systems generally feature only two analog inputs and outputs on one PCI card and fewer simultaneous playback tracks. Some recording and editing software applications are standalone packages that do not come with any hardware components. Note that MIDI-sequencing software packages now support digital audio recording and playback (see the following section).

A.2.5. Sequencers: MIDI and digital audio recording and editing applications

A MIDI sequencer is an important component to the web audio studio if you plan to compose music with several synthesizers or tone generators. In the past few years, the industry has seen a convergence between MIDI and digital audio applications. It is now standard to buy one application, such as Studio Vision Pro or Logic Audio, that records both MIDI data and digital audio. The number of simultaneous MIDI and audio playback tracks depends on your computer hardware, CPU speed, and external I/O sound card.

The MIDI component of a sequencer functions like a standard digital audio application with all the familiar controls -- record, stop, play, fast forward, rewind, loop mode, and so on. However, a MIDI sequencer does not actually record the sound output of a synthesizer. It merely records the actions that triggered certain sounds, much the same as an old-time piano role.

Because a sequencer records actions only as text-based commands, it has many speed and editing advantages over hard-disk recording. A 10-minute MIDI composition with 4 separate playback tracks takes only 40 KB on your hard disk, while the same digital audio file requires a giant 200 MB in disk space.

The main disadvantage to MIDI is that you can playback and record only the limited palette of sounds stored inside your synthesizer. MIDI cannot store, record, or transmit digital sounds. If you record voice-overs or live instruments, you will have to use the digital audio hard-disk recording feature of your MIDI sequencer. Note that most companies offer free trial demos of their MIDI software packages on the Web.

A.2.5.1. Pro option

High-end sequencing packages offer professional I/O support for Digidesign's Digital Audio Engine or other proprietary systems, real-time effects plug-ins, and unlimited simultaneous MIDI tracks. Note that each package listed in both the pro and budget options includes the compatibility information with Macintosh and Windows operating systems.

  • Steinberg Cubase Audio XT 3.5 MIDI* and multitrack digital audio with real-time effects and EQ (list $799/street $550) (Macintosh and Windows 3.1, 95, 98) * Best Buy

  • Opcode Studio Vision Pro 3.5 MIDI and multitrack digital audio, easiest MIDI application to use (list $995/street $700) (Macintosh only)

  • Emagic Logic Audio 3.0 MIDI and multitrack digital audio (list $799/street $550) (Macintosh and Windows 95, 98)

A.2.5.2. Budget option

Low-end sequencing packages provide few effects-processing features, no I/O support, and in some cases no digital audio recording or editing.

  • Steinberg Cubase AV* no frills MIDI and multitrack digital audio, 8 audio tracks, 16 MIDI tracks (list $99/street $79) (Macintosh and Windows 3.1, 95, 98) * Best Buy

  • Emagic, Logic Audio Discovery 1.1 MIDI and digital audio (list $299/street $199) (Macintosh and Windows 95, 98)

  • Opcode, Vision 3.5 MIDI and multitrack digital audio (list $395/street $279) (Macintosh only)

A.2.6. Synthesizers and tone generators

Even the most rudimentary forms of sound design require some type of musical element or ambient background texture. The easiest way to generate different background washes and musical sounds is with a MIDI synthesizer or tone generator. If you plan on doing sound design and music composition, you will need to purchase a synthesizer keyboard or a MIDI controller with an outboard tone generator.

Avoid synths that have built-in sequencers; you will not need them if you use a computer-based MIDI sequencer application. There are a huge variety of keyboards on the market that cater to a wide range of tastes. Spend a good amount of time listening to the built-in presets and features before you buy. If you are purchasing your first keyboard, buy one that produces a wide range of sounds, from piano to strings to percussion.

A.2.6.1. Pro option

Professional keyboards have weighted piano keys, extra RAM for longer-playing waveform samples, a minimum of 64 voice polyphony (64 simultaneous MIDI instruments), additional DSP chips for ultrarealistic audio replication, and some method or form of input card for importing custom digital samples. If you have several synthesizers, as is common in professional studios, you will need to purchase an additional MIDI patchbay to route the MIDI signals to your MIDI controller.

  • Korg Trinity Rack Synth,* 48 kHz samples, best prestocked in-house sounds (list $1,400/street $1,200) * Best Buy

  • Kurzweil K2500, no specs or pricing provided

  • Korg Z1 Analog Synth* with physical modeling (list $2,800/street $2,000) * Best Buy

  • Yamaha EX-5

  • Emu Esynth

A.2.7. Mixers

The mixer is the Grand Central Station of the sound studio. Audiomixing boards connect and route all the input and output signals from one component to another. Mixing boards also have signal processing capabilities such as equalization and effects for outboard reverb and delay. Mixers save you from the headache and hassle of patching together different pieces of equipment for common, day-to-day studio tasks. Mixers are often used for routing output signals from a DAT machine, CD player, or microphone into a sound card and back out to a set of studio reference monitors.

Five tips for selecting the best audio equipment retailer

 
  1. Get a recommendation from someone you trust. When you get a good recommendation, make sure to get the name of a specific salesperson. When you speak with the salesperson, mention the name of the customer who referred you.

  2. Check to see if the company has a high employee turnover rate. Ask the salespeople how long they have worked at the company.

  3. Go in with a question you know the answer to, to see if the salesperson gives you an honest response. The salesperson should be knowledgeable enough to properly answer your questions. Especially make sure they are up-to-speed on digital audio. Ask a salesperson what MIDI stands for and see if they give you an informative answer. They should at least tell you that MIDI stands for Musical Instrument Digital Interface.

  4. Call the Better Business Bureau to find out if any complaints have been filed against the company.

  5. Finally, check out a music retailer's commitment to customer service. A good music retailer will help you buy the product you need, even if they have to refer you to another retailer who has the item in stock. An honest retailer will ask questions to find out what components suit your needs instead of only pointing you in the direction of overstocked items the store wants to push. Ask the salesperson if he or she has to meet sales quotas. A consumer-friendly retailer will not have sales quotas. (Remember that all sales people have some type of commission plan, but not all stores implement sales quotas.) Generally, the large nationwide retail outlets have high sales quotas and heavy employee turnover. Finally, call them on the phone before you go in and see if they are responsive to your questions.

Once you find a good audio equipment dealer and have purchased your gear, stay in touch with the salesperson. A good salesperson will be more than happy to provide information and technical help. The more a salesperson gets to know you, the more likely he or she will give you honest and straightforward answers. Do not ask 30 minutes of questions and then run across town to buy the same item for 5 bucks less elsewhere.

The key component of a mixing board is the signal-to-noise (s/n) ratio, measured in dB. A good mixer will introduce less noise into the signal than a poor one. The best way to tell if a mixer has low noise is to plug in some headphones or monitor speakers, turn up all the faders on the board without turning on any sound, and then turn up the main output levels. If you hear excessive hiss and noise, then the mixer has a poor s/n ratio. If you hear only a little or none at all, then the mixer has a good s/n ratio.

A.2.7.1. Pro option

Professional-grade mixers use good electronic components for every knob, circuit, and switch to avoid adding system noise into the audio signal. One of the key components of good mixer is high-quality mic pre-amps. Expensive mic pre-amps can drive up the price of a good mixer considerably because a mixer needs a mic pre-amp for every input channel.

  • Allen & Heath Mix Wizard 20 Analog 20 x 8 x 2* mixer with eight mic inputs, four-band EQ with sweepable mids (list $1,295/street $1,100), 101dB signal-to-noise ratio * Best Buy

  • Mackie CR1604-VLZ Analog 16 x 4 x 2 mixer with 16 mic inputs (list $1,199/street $899), 90dB signal-to-noise ratio

  • Alesis Studio 32 Analog 16 x 4 x 2 mixer with 16 mic inputs, 16 inline tape returns (list $1,200/street $1,000)

A.2.7.2. Budget option

Low-end mixers use cheaper components and produce more system noise. Even a relatively small 12-channel mixer has over 400 knobs, switches, and inputs alone, excluding the internal circuitry. Unless manufacturers are paying pennies for these components, they cannot make a profit on a $500 mixer. Compared to 10 years ago, the gap in sound quality between super high-end models and low-end models is closing. Most studios, with the exception of a few high-end venues, use Mackie mixers.

  • SoundCraft Spirit Analog 12 x 2 x 2 mixer* with four mic inputs (list $350/street $295), 90dB signal-to-noise ratio * Best Buy

  • Mackie MS1202-VLZ Analog 12 x 2 x 2 mixer with four mic inputs (list $429/street $349), 88dB signal-to-noise ratio (The 1402-VLZ offers linear faders for a little bit more money.)

A.2.8. Digital mixers

Any of the new digital mixers can boost the audio quality of a studio. One reason for this is that the audio signal remains entirely in digital form once it enters the mixer and is routed through various internal effects without the degradation caused by repeated digital-to-analog (D/A) and analog-to-digital (A/D) conversions. Although the price tag may seem hefty, digital mixers are a bargain for a new installation because they include many channels of high-quality compression and other effects that otherwise would have to be purchased as separate pieces of gear. They also offer snapshot and synchronized automation features that make recording sessions very efficient.

A.2.8.1. Pro option

More and more manufacturers are producing all-digital mixing boards with superior built-in effects and super-high signal-to-noise ratios. Mixing digitally avoids the danger of getting analog system noise. If you have a high-end Pro Tools system with digital inputs hooked up to a digital mixer, you can stay entirely in the digital realm, from multitrack to mix-down.

  • Mackie Db8 72 input channels (list $10,000)

  • Panasonic DA-7* 48 input channels (list $5000) * Best Buy

  • Yamaha O3D Digital 26 x 4 x 2 mixer with eight mic inputs (list $3,699/street $2,999), 110dB signal-to-noise ratio

A.2.9. Studio reference monitors

High-quality studio reference speakers, or monitors, accurately reproduce a "flat," transparent representation of your audio without adding coloration, distortion, noise, or equalization. Consumer stereo speakers, by contrast, are designed to boost the high and low audio frequencies to sound good on the sales floor. Unlike home stereo speakers, reference speakers are designed to give you the most accurate sound, not the most pleasant.

Experienced engineers rely on their favorite reference speakers to give them a consistent reference to their sound. They rely on the same reference speakers or a set of speakers every time they mix-down their audio tracks. Serious engineers will even bring their favorite reference monitors along from one recording studio to another. Just as every computer monitor screen displays colors slightly differently, every brand of studio "near field" reference speakers produce a slightly different sound. Most good-quality reference speakers give an accurate, "flat" representation of the audio frequency spectrum.

The most important step is to use the same set of speakers every time you listen to your audio mixes. A favorite trick of savvy recording engineers is to play popular CDs on their reference speakers to hear how other mixes sound on their system.

A.2.9.1. Pro option

The professional choice is to useself-powered studio speakers. A self-powered, gnarled monitoring system contains a power amp built into each speaker. There are several advantages to using self-powered speakers: you eliminate the need for a noisy standalone power amp; you are guaranteed that the power going to your speakers is always the right amount (often standalone power amps deliver too much or too little power to your speakers); and it's easier to transport self-powered speakers if you travel to another studio.

  • Event 20/20 Self-powered,* nearfield monitoring system (list $1,000/street $999) * Best Buy

  • Genelec 1029A Self-powered, nearfield monitoring system (list $2,000/street $1,800)

  • Hafler Self-powered, nearfield monitoring system (list $1,400/street $1,200)

  • Mackie HR 824- Self-powered nearfield monitoring system (list $1,500/street $1,000)

A.2.9.2. Budget option

The standard option is to use a pair of reference monitors powered by a standalone power amp. Alesis sells the relatively inexpensive RA-100 power amp for $299.

  • Event 20/20 reference speakers* (list $400/street $340) * Best Buy

  • Tannoy SBM reference speakers (list $295/street $250)

  • KRK K-ROK reference speakers (list $500/street $425)

A.2.10. Effects processors

Ever since the first spring box reverb unit took the rock world by storm, effects processors have become the all-powerful magic box of the sound studio. Instantly replicating the sound of huge cathedrals, concert halls, and echoing canyon walls, effects processors offer the sound designer a world of possibilities that were once cost-prohibitive or completely impossible. As more recording and editing is performed on the computer, effects processing will be performed solely through software plug-ins instead of outboard gear. For the time being, most people find it more convenient to use both outboard effects processors and internal software plug-ins.

A.2.10.1. Pro option

High-end effects processors give you better overall audio fidelity and longer, more accurate reverbs and delays. A rich sounding 10-second delay or reverb requires tremendous processing power and RAM.

  • TC Electronic, Wizard/M2000 Reverb,* delay, chorus, flange, and more (list $1,995/street $1,600), 20-bit/20-bit ADC/DAC, max delay time 1,200 ms, XLR AES/EBU digital outputs * Best Buy

  • Lexicon, PCM90 Reverb, delay, chorus, flange, and more (list $2,995/street $2,500), 18-bit/18-bit ADC/DAC, max delay time 2500 ms, RCA S/PDIF digital outputs

A.2.11. DAT (digital audio tape) recorders

A DAT is a miniaturized version of a VHS tape and is the professional recording standard for stereo mix-downs and mastering. Even if you choose to store your stereo master recordings as audio files on a hard disk or CD-ROM instead of a DAT tape, it is certain that clients will bring you their audio source materials on a DAT at some point in time. If you are creating a professional studio, you will need a DAT player.

If you are on a tight budget and do not plan on working with high-end clients, you can skip the DAT player and mix-down your audio to stereo master files for storage on a hard disk or backup storage media. As the prices of CD recorders keep dropping, more and more digital audio professionals are switching from DAT stereo masters to CD-ROM audio masters. However, most professional recording and mastering engineers still prefer to use DAT for final mix-down masters.

A.2.11.1. Pro option

DAT machines feature high-speed tape reel mechanisms that are prone to stop working, or worse, eat your tape and ruin a good recording session. With high-end machines, you are more likely to get reliable playback and recording over time as well as higher-quality analog to digital converters.

  • Panasonic SV 3800 DAT* (list $1,695/street $1,400). 18-bit/20-bit ADC/DAC, 92dB signal-to-noise ratio, XLR inputs. * Best Buy

  • Sony PCM R500 DAT (list $1,695/street $1,400), 20-bit/16-bit ADC/DAC, XLR inputs.

  • Tascam DA-45 MKII DAT (list $2,500/street $1,900), 24-bit/20-bit ADC/DAC, 113dB signal-to-noise ratio, XLR inputs.



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