Make Beautiful Music: Build a Professional Digital Audio Workstation

The good news is that you don't need to be a music specialist to build music systems. From the system-builder's perspective, a Digital Audio Workstation has a lot in common with other data-intensive applications, such as file servers and video-editing systems. In fact, with just a little knowledge of current state-of-the-art audio interfaces and software, a knowledgeable system builder can assemble a Digital Audio Workstation with readily available, off-the-shelf components. The system will work reliably and produce great results.

But first, what is a Digital Audio Workstation, anyway? A DAW is generally a rock-solid box built for, and dedicated to, recording and editing digital audio. It's that simple.

DAW applications include music production; multimedia development; broadcast work for radio or television; and video/film sound design and post-production. A typical user includes the musician looking to produce their own CD; an audio engineer doing post-production work for TV, or a corporate media director doing in-house advertising with music "on-hold." For all of them, a DAW provides the means to do high-quality audio recording and processing using a low-cost PC.

CHOOSING AN AUDIO INTERFACE

There is one exception to the off-the-shelf nature of the parts list: the audio interface. Which interface to choose depends on your specific application and other factors.

To choose an appropriate interface, you must first understand your client's needs. The number and types of simultaneous inputs is a critical factor. Will this DAW support a simple, one- or two-track recording and editing application? Or will the client be recording multiple instruments and voices simultaneously? Will eight channels be enough? Will the client be recording or adding digital effects to many tracks simultaneously, or will they do mastering?

Interfacing with other equipment is also important. Will this workstation need to interface with other systems via digital audio standards like SP/DIF, a popular digital audio interface developed jointly by Sony and Phillips, or ADAT, another digital audio standard? If so, your choice of audio hardware will likely need to support both that and MIDI, the musical instrument digital interface . While I won't delve into the many features of popular audio interfaces and software here, I will point out some of the more popular ones.

There are many good choices for a solid audio interface. In fact, soundcards and on-board audio with state-of-the-art 24-bit resolution and sample rates of 96 KHz are readily available. PCI-based cards will still handle the most simultaneous channels of audio. In addition, USB and Firewire devices are growing in popularity; they offer portability and easy installation. The following table lists some of the available solutions, along with their relative strengths and weaknesses:

If you're looking for even more alternatives, there's a very complete list of audio interfaces at Computers and Music.

CHOOSING AUDIO SOFTWARE

No matter which audio interface you use, you'll need robust audio software to make it all work. At the very least, audio software lets you store and play back streams of audio data captured by the audio interface. But it can also do a lot more. Popular software packages generally provide an organized user interface, including utilities to configure audio software and the means to clone, edit, or delete audio tracks. Other features can include recording and editing MIDI events, "ripping" MP3s, and adding effects such as reverb, chorus, and compression to your takes.

When choosing audio software, let your client's requirements, personal taste, and budget guide you. Also, remember that feature-limited or 30-day demo versions are available for most packages. Keep in mind that the more sophisticated, high-end packages have a steep learning curve; many contain features that you or your client will never use. For that reason, it pays to carefully examine an audio software package, and to decide which features are really required. Also, if your client already has experience with one or more high-end packages, sticking with that package will save your customer time during initial implementation.

The following table lists some of the more popular audio software packages:

CHOOSING AN OPERATING SYSTEM

The Apple Macintosh line of computers has long been a popular choice for audio applications. For years, Apple's streamlined user interface and strong software support for multimedia made the Mac a favorite with audio engineers, artists, and musicians. But I believe Windows-based PCs are today a better choice for system builders. There is a wide range of audio hardware and professional audio software available for Windows-based PCs, and that gives builders more control over the configuration and total cost than they would have with a Mac.

For this project, we will be buying a new audio interface that takes advantage of the stability, new features, and versatility of WindowsXP. The Microsoft OS has the best features for digital audio, along with stability and the best prospects for compatibility with future software enhancements.

While I appreciate the stability and versatility of Windows XP, I don't see the need for the additional features of the Professional edition. As a result, I generally save the difference in cost and use XP's Home edition. You'll find tips for tuning XP for audio applications later in this article.

What about Unix and Linux, you ask? While Unix and its open-source relation are both powerful and mature multi-tasking operating systems, there is very little audio software available for them. And there's even less support in terms of drivers. For that reason, I do not recommend Linux/Unix systems as digital audio workstations.

CHOOSING PARTS

A system is the sum of its parts. While a DAW has much in common with other PCs, there are some special, make-or-break considerations. The audio software, low-level drivers, and hardware must all work together seamlessly to handle simultaneous streams of audio data. Problems with audio data can result in pops and crackles that will mar otherwise perfect "takes." Finding and fixing them can take many hours.

For that reason, in selecting a motherboard, processor, and memory, we will consider both our software publisher's recommendations and any knowledge of the past performance of the hardware with our software. Also, we will look closely at component features like fan noise and vibration. While these are trivial issues in an office setting, in the studio, they can cause big trouble.

For audio applications, I like the Antek Sonata case. It was specifically designed to be very quiet, a critical requirement for recording. I've also sourced a very quiet and speed-adjustable CPU-cooling fan. You can find lots of fans, power supplies, and other noise-conscious components at End PC Noise.com and PC Toys.

Today's processors, like the Intel P4 2.6-GHz CPU, will handle all but the most challenging multi-track recording needs. It's equally important to find a rock-solid motherboard and CPU combination that works well with your audio software and hardware. While there are many good choices for high-performance motherboard/CPU combinations, the audio industry has regularly heard hardware and software vendors state their preference for Intel. For this project I chose an Intel 865PERL motherboard with support for SATA drives, RAID storage, and Firewire (IEEE1394a).

As for the drives, the increased performance, size, and affordability of today's 7200-rpm drives with 8 MB of cache makes our choice easy. The use of 7200-rpm drives can avoid performance issues that arise with older, slower-spinning drives. I chose Maxtor's Ultra series SATA drives, which boast 150MB/Sec. throughput, an average seek time of less than 9.4 msec., and renowned reliability. If you are curious or have concerns about serial-drive compatibility, check out Maxtor's SATA page.

By the way, that throughput is in bytes, not bits! SATA boasts 1.5 gigabits per second, which is equivalent to a data rate of 150 MB/sec. For a very good overview, visit the Serial ATA site. There is also a good white paper available from Maxtor on SATA and SAS (serial-attached SCSI) compatibility; you can download the PDF file here .

PARTS LIST

Now let's take a look at our components. Here's what I'm using to build this system, and why:

-- Motherboard: Intel 865PERL. Rock-solid board w/ Firewire, SATA, RAID.-- CPU: Intel P4/2.6Mhz. Hyperthreading and 800-Mhz front side bus.-- CPU Cooling: ThermalTake P4SPARK7PLUS. Super-quiet fan with adjustable speed. How quiet? Just 17 dBA at 20 C/10.42 CFM/1300 RPM.-- Video: GeForce 5200. Dual-head AGP (accelerated graphics port). Using the AGP slot improves the overall performance of the box, but what we are really looking for in this card is the dual-head. Audio operations are desktop-intensive. So having two monitors allows for several applications to be running -- and visible -- at once. In fact, for serious digital audio, it's a must. I also like the fact this card because it's easily available and, at less than $100, very cost-effective.-- Memory: 1 GB. Two 512-MB DDR 400 (512 MB minimum).-- Disk: Maxtor Ultra Series SATA. 80 GB for the OS, two 200-GB SATA for data.-- Case (with fan): Antek Sonata. Quality case with quiet, 380-watt power supply, two 120-mm. controlled fans, airflow design, and rubber grommets to reduce disk vibration.-- CD-RW: Plextor PlexWriter 48/24/48A. Good speed, reliable supplier.-- Audio Interface: MOTU 828mkII. Firewire audio interface by Mark of the Unicorn.-- Audio Software: Sonar3 Studio. Professional-quality software.-- Operating System: Windows XP Home edition. Solid OS for audio with many available drivers.-

PUTTING IT ALL TOGETHER

Now that we have our components assembled, it's time to start building. Let's get started:

Step 1: Assemble your parts and tools in a clean, well-lighted workspace.

Step 2: Ground yourself, both mentally and physically. On static, I've heard the arguments both ways, but I don't want to take the chance. I wear an anti-static wrist strap.

Step 3: Install the CPU and fan on the motherboard. Doing this before you have the motherboard installed in the case makes it easy. Apply a thin, even layer of the grease to the mating surface of the chip. Position the heatsink/fan assembly. Attach the clips.

Step 4: Using the motherboard diagram or manual, attach headers, connections to leads, and front panel. Again, I prefer to do as much of this as possible before mating the motherboard to the spacers. It's simply easier this way.

Step 5: Install the motherboard. Get a snug fit on all screws and standoffs to minimize vibration and noise. Use all the spacers called for.

Step 6: Install DIMMs (dual in-line memory modules). In our case, there are two: One to DIMM0 of Channel A, and the other to DIMM0 of Channel B.

Step 7: Install the AGP video card. Having only a video card installed on turn-up minimizes potential problems during the OS installation.

Step 8: Configure jumpers on the CD-RW and hard drives for Master/Slave/CableSelect. Configure the OS driver as IDE primary master, 0 and CD-RW as secondary master, 0.

Step 9: Install hard disk, diskette, and CD-RW drives. Antek recommends installing 5-1/4 inch devices in the lower slots and 3-1/2 inch devices in the higher slots.

Step 10: Dress and secure the cabling. Unsecured cable can interfere with cooling and generate unwanted noise.

Step 11: Double-check all your work. Make sure all cables are neatly dressed and bent gently to provide the maximum airflow. Check all screws for tightness. Check connectors for polarity.

Step 12: Attach the system's mouse, keyboard, and monitor. Then plug it all into a good surge protector.

Step 13: Power up the system, and configure the BIOS settings. Review every setting and confirm. If you need the 865PERL complete manual (all 132 pages!), get a PDF download from Intel.

Step 14: After the BIOS is set but before you save and exit, check the hardware monitor from BIOS. Confirm that the temperatures and voltages are OK along with the fan speed. Save and exit the BIOS. It's always wise to monitor any PC for at least 20 minutes from BIOS before installing the OS.

Step 15: Install the OS. Boot from the OS setup CD. Then partition and format the drives with NTFS (NT file system).

Step 16: Install PCI cards and drivers.

Step 17: Burn-in and benchmark.

TUNING WINDOWS XP FOR AUDIO

Windows XP Home edition, like other Windows versions, contains many features and functions that are not, strictly speaking, essential. From an audio-workstation perspective, XP's excessive graphic activity, system-maintenance functions, background tasks, and automated hardware-management tools can rob the system of valuable resources better devoted to the audio application. That's where tuning comes in. Also, tuning allows you to adjust the priorities of individual processes so that the audio processing mostly takes precedence.

Here are my top audio tweaks for Windows XP:

• Switch off Automatic OS updates.
• Disable system sounds.
• Switch off hibernation.
• Disable power-saving options.
• Disable fast user switching.
• Set graphics options for best performance.
• Set non-essential services to manual. These include automatic updates, DHCP client, task scheduler, and Telnet.

For even more on tuning Windows XP for digital audio, visit MusicTech Tips and click on "Tuning Windows XP For Digital Audio Use." Another useful resource is this Windows XP for Audio Workstations page.

DIGITAL-AUDIO MAINTENANCE TIPS

It is popular to "ghost" or back-up the OS partition to make it possible to recover quickly in case of trouble. Remember all those tweaks to the OS, driver installations, and other functions? Both Norton Ghost and Partition Magic are useful pieces of software to deal with backing-up and partitions.

Also, while it is convenient and trendy to have every box attached to the Internet, by doing so you expose your system to spyware and other unwanted software. Be cautious with your clients' DAWs. Don't install unnecessary hardware or software.

Professional audio engineers defragment their disks often, and so should you. For digital audio recording, this is not considered just an occasional performance-enhancing procedure, but a necessary task. Do it often. Whenever you experience recording anomalies, try this first.

Building and maintaining DAWs is an interesting challenge. Enjoy your DAW building experience!

ANDY MCDONOUGH is a professional musician, composer, voice actor, engineer, and educator happily freelancing in New Jersey.