Studio in a Box

EM looks at the latest models of personal digital studios, which are hardware digital multitrack recorders that offer numerous features in one device.
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The portable digital studio (PDS) is a self-contained digital multitrack recorder with a built-in mixer, onboard effects, and editing capabilities. It is not surprising that the PDS has continued to grow in popularity since EM last explored the product category (see “The Incredible Shrinking Studio” in the July 2001 issue of EM at When space is at a premium, a device that can house the most important features of an entire studio under a single roof, as well as minimize cabling and the physical repatching of external gear, can be enticing to someone building a personal studio.

Stability is another reason people gravitate toward the PDS. Because they are essentially single-purpose computers, problems you may experience with a desktop computer, such as conflicts between an operating system and audio drivers, don't exist. Typically, an operating system upgrade on a PDS gives you new features specifically directed at recording-studio functionality because there is little need to upgrade anything else.

The self-contained nature of the PDS makes multi-track recording at almost any location easy. Most models have generous amounts of hard-disk space, and because all of the mixing apparatus is built-in, the PDS can trump laptop computers as self-sufficient recording devices.

Meet the Composers

The number of portable digital studios has more than doubled since our last roundup, and some of the features anticipated then are now a reality. For example, several of the latest models have General MIDI synthesizers or drum-machine-style sequencing for an onboard bass and percussion sound set.

An escalating and divergent list of features, such as enhanced sampling rates and resolutions, virtual tracks, and computer connectivity, draw today's crop of PDS units farther away from their cassette multitrack origins. Support for legacy storage devices such as SCSI has disappeared from all but a few of the current models; yet all have internal mixdown capabilities and some form of access to the external world, such as USB ports, CompactFlash cards, or CD-RW drives.

A complete survey of what's on the market would be a maddening exercise in redundancy because there is a wide range of systems available that have similar feature sets but vary greatly in price. Instead, I chose to examine units representing both poles of the affordability range. A complete head-to-head comparison of each recorder's features would require an enormous amount of editorial space. For this article, I will discuss the features that help define the worthiness of a PDS for various types of users. (For more information, see the Portable Digital Studio Specifications and Features tables.)

The DPS24, a 24-track machine from Akai, has an embarrassment of professional features, such as 100 mm touch-sensitive faders. Although the DPS24 is portable, it's large and somewhat heavy, so be sure to have someone help you when you need to move it.

The Fostex VF160EX, which records as many as 16 simultaneous tracks, sports a generous 40 GB hard disk and lets you burn your finished product to disc using a built-in CD-RW drive. The Fostex MR-8 writes to CompactFlash cards instead of using a hard disk for storage. Consequently, it doesn't have any moving parts that can dislodge in transit, and it's less expensive than the VF160EX.

The Korg D1200mkII has an adjustable-angle display and an easy-to-navigate interface. Its high-end sibling, the Korg D32XD, is just as easy to use, but it gives you more tracks, motorized faders, and 24-bit, 96 kHz recording. The Korg ToneWorks PXR4 is a handheld 4-track PDS that records to SmartMedia card and has USB connectivity (see the sidebar “The Palm-size PDS”).

Roland's VS-2480 is a 24-track recorder that sounds terrific and goes to the head of the class for expandability. Meanwhile, the Boss BR-1600CD occupies a midpoint in our roundup's price range. The BR-1600CD is brimming with great effects and gives you immediate access to their parameters.

The Tascam DP-01FX has random-access, digital-audio recording, editing, and mixing features while maintaining an easy-to-grasp, channel-strip-style mixing surface. Tascam's larger, more flexible 2488 system has 24-track playback, varispeed capabilities, a built-in CD-RW drive, and a General MIDI (GM) synthesizer.

At the top of Zoom's current PDS roster is the MRS-1608CD, which has a CD-RW burner, an internal 40 GB hard disk, and a built-in loop library, among other features. Zoom's MRS-8 has great effects, extremely flexible bouncing options, separate drum-machine and bass tracks, and pads to trigger them — all in a remarkably small package. Zoom's PS-04, which has the smallest footprint in the company's line of PDS products, has SmartMedia storage, bass and drum tracks, and a built-in mic (see the sidebar “The Palm-size PDS”).

The dimensions of these recorders range from pocket-size to sizes that stretch the definition of portability, such as the Akai DPS24, the Korg D32XD, and the Roland VS-2480. Note that those three units stand apart from the pack because they have a variety of hardware expansion options and use long-throw, motorized faders — features that are difficult to host in a smaller package.

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FIG. 1: Don''t let its size fool you: the Zoom MRS-8 packs a streamlined, rich feature set into a small, well-organized, battery-powered package.

Many PDS units accommodate electric guitar and bass by providing high-impedance instrument inputs on the front panel, perhaps indicating that the machines are designed to accommodate the guitarist's or the bassist's home studio. Even if that's true, the growing adaptability of the PDS makes it equally ideal as a tracking device for live gigs, a field recorder, or as a readily accessible demo machine.

Although it is one thing to shoehorn a ton of features into a single device, it is a rare achievement to make those features easy to reach and understand. Over the years, manufacturers have worked hard to make the complex PDS user interface less daunting. With that in mind, I examined each of the units discussed in this article with as little consultation of the manual as possible, on the premise that a user-friendly design should not be inversely proportional to the feature set. In most instances, that technique worked pretty well. In a few cases, however, consulting the manual stopped me dead in my tracks.

Count Trackula

One of the first considerations when choosing a PDS is the number of simultaneous tracks available for recording and playback. If you want to record an entire band at once, you will need as many simultaneously available inputs and tracks as you can get. If you need to record only MIDI tracks with an occasional vocal, electric guitar, or bass, you may find that you can get by with a device that offers two tracks of simultaneous input at a time. Although a recorder may sport the number of physical inputs you need, remember that track counts and physical inputs differ greatly. For example, although Zoom's MRS-8 gives you eight audio tracks, you can record only two tracks at a time (see Fig. 1).

Many devices that boast higher track counts or more inputs and outputs have slightly different limitations: choosing the highest-quality bit depth and sampling rate will affect the number of tracks available for recording and playback. Korg's flagship D32XD has 32 simultaneous tracks of playback and 16 tracks of recording, but only at 16-bit resolution. Furthermore, you are limited to eight analog inputs unless you spring for the AIB-8 input-extension board ($350). At 24-bit, 96 kHz settings, it tops out at eight tracks of playback with four simultaneous record tracks. The Akai DPS24 has 24 tracks of playback and recording, except at its 96 kHz sampling rate, which halves the record and playback track count.

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FIG. 2: With the help of its ADAT optical inputs, the Fostex VF160EX can record a total of 16 tracks at once.

Other recorders, because of either a simpler design or a fixed sampling rate and bit depth, have an unvarying number of inputs and track count. The Fostex MR-8 and the Zoom MRS-8 maintain two tracks of input and eight tracks of playback. The Boss BR-1600CD has 8 simultaneous recordable tracks and 16-track playback with 16-bit, 44.1 kHz audio. Tascam's 2488 gives you 24 tracks of playback and 8 simultaneous recordable tracks at 16- or 24-bit resolution. The Fostex VF160EX will record eight tracks of analog input, but it can simultaneously record another eight channels through its optical ADAT Lightpipe inputs (see Fig. 2).

Roland's VS-2480 holds as many as 24 playback tracks, depending on bit depth, sampling rate, and recording mode. (As with earlier Roland PDS units, the VS-2480 has various levels of its proprietary R-DAC compression scheme, as well as linear 16- and 24-bit modes, which affect track count and the amount of disk space used.)

Ways In and Far Outs

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FIG. 3: The diminutive form factor of the Fostex MR-8, combined with a pair of XLR jacks, CompactFlash storage, and battery power make it a good choice for recording outdoors.

The number and types of inputs and outputs that a PDS has is an important consideration. A unit that has a limited number of XLR connectors will affect your choice of microphones. If it has only two phantom-powered XLR inputs, you will need some other means of connecting and powering any additional mics that you want to use.

In addition to a built-in mic, which is suitable for scratch tracks and slating, the only inputs that the Zoom MRS-8 has are a balanced ¼-inch jack and a single XLR/¼-inch combo jack. The Fostex MR-8 trumps the MRS-8 with its pair of XLR and unbalanced ¼-inch inputs (see Fig. 3). The midprice Zoom MRS-1608CD gives you eight phantom-powered combo jacks, while the Boss BR-1600CD has eight phantom-powered XLR jacks, eight balanced ¼-inch inputs, and a high-impedance guitar input.

The Zoom MRS-8's single pair of left-and-right RCA outputs may be a deal breaker for some consumers. The Fostex MR-8 has only a single pair of unbalanced ¼-inch analog outputs, but it also sports a second set of headphone jacks and optical S/PDIF output, so that you can simultaneously mix digitally to a compatible external recorder. The Tascam DP-01FX has two unbalanced ¼-inch jacks for its stereo mix output, as well as a second pair of unbalanced ¼-inch jacks for monitor outs, two ¼-inch effects returns, and a ¼-inch send.

You should also consider the other types of I/O that you will need in addition to audio I/O. If you need word-clock sync, the Akai DPS24 is the only unit discussed in this article that supports it as master or slave. The Korg D32XD has word-clock I/O as part of the ADAT output option (DIB-8, $125), and the Roland VS-2480 supports word-clock input only. The VS-2480, however, can connect to other devices that share its proprietary R-Bus system, which provides a bridge to a host of expansion options, including analog-input expanders and digital mixers, AES/EBU and computer connectivity, and a direct digital-audio connection to some Roland synths. As I mentioned earlier, many of the units in this roundup have USB connectors, giving you a means to off-load audio data, backup a project, and update your operating system.

MIDI is pervasive in many different aspects of the recording process, and every recorder reviewed here uses MIDI to supply synchronization with MIDI Clock or MIDI Time Code (MTC). One limitation of the entry-level Fostex, Tascam, and Zoom recorders is that they support only one-way MIDI communication with their single MIDI Out port. The absence of a MIDI In port means that those units must be the master clock when synchronizing and recording sequenced arrangements. That can be a drag, considering how much easier it is to create tempo tracks in your DAW software. More significantly, lack of a MIDI Input means that you cannot use the device to record fader moves to a sequencer and then play them back for MIDI-automated mixdown (which I will discuss in a moment).

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FIG. 4: Dedicated, extra-large knobs make Tascam''s DP-01FX effects editing and basic pan and EQ parameters instantly accessible.

Parameters on Parade

Just as the first digital synthesizers came with opaque user interfaces, early portable digital studios were hampered by numerous menus, submenus, and pages that were often difficult to navigate. Today's PDS, however, gives you the immediacy of dedicated hardware controls, conveying the internal routing-buses, sends, returns, and effects as graphically as possible.

Considering the relatively rich feature sets packed into the diminutive, lower-end Fostex, Tascam, and Zoom units, they are remarkably easy to use: I was able to get up and running on them with hardly a glance at their respective manuals. Controls for the pared-down effects array of the Fostex MR-8 are at your fingertips. You can select mic- and amp-simulation effects from buttons on the surface of the unit, select delay or reverb types from another set of neatly arranged buttons, and control reverb and delay time from a dedicated top-panel knob. Below the simulator buttons are effects send-level knobs, and to the right of those, you have a choice of three mastering presets, which you can apply to the stereo buses.

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FIG. 5: The Korg D32XD sports motorized, long-throw faders; an adjustable-angle display; and 24-bit, 96 kHz recording capabilities.

The Tascam DP-01FX has a considerably more varied and complex group of effects, but the unit's large, dedicated knobs for each channel send and a knob for editing effects parameters make them easy to handle (see Fig. 4). Many of the basic controls for each channel, including EQ and pan position, are also easy to access.

Navigating the Zoom MRS-8 is a cursor-and-menu affair. Nonetheless, editing on it is a breeze because of its logically laid out display and intelligently integrated cursor-navigation system. Pressing the Track Parameter button lets you use the cursor up and down buttons to access each track's EQ, pan, and effects send parameters. Left and right cursors access neighboring tracks while letting you remain on one parameter, such as effects send levels or pan position. The Value knob sits directly to the right of the cursor buttons. Despite its lack of dedicated knobs and buttons, navigating the MRS-8 is a remarkably quick and ergonomic experience. The Fostex MR-8, the Tascam DP-01FX, and the Zoom MRS-8 do not have jog or shuttle features

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FIG. 6: The Q-Link pots to the right of the Akai DPS24 display correspond with the function buttons at the bottom of the display and allow for quick editing of any onscreen parameter.

The user interfaces of the Korg D1200mkII and the D32XD have evolved somewhat from their antecedents to accommodate new features. For example, some of the features that used to be buried within menus, such as amp- and mic-modeling parameters, are accessible from an array of knobs on the recorder's surface. The D32XD touch screen feels considerably more responsive and precise than the first touch screen models (I often reverted to cursor navigation with earlier models). Nevertheless, much of the navigational logic of their earlier systems remains. The angle of the displays on the D1200mkII and D32XD are adjustable (see Fig. 5).

The Akai DPS24 is an exceptionally powerful machine that is more difficult to grasp at first glance. Stenciled, color-coded directions on the instrument's surface indicate multifunction controls, but it's not clear how to access secondary functions without diving into the manual. An audio tour of the unit that was stored on the hard drive was the key to comprehending the DPS24's basic functions. As visually intimidating as the DPS24 may seem, once you realize that its Q-Link knobs are context-sensitive controls based on the parameters that you selected with the function buttons, you are well on your way to swiftly getting around much of the unit's feature set (see Fig. 6).

Navigating the surface and menu structure of the full-featured VS-2480 can be daunting, but the included two-button mouse, along with an optional VGA monitor, makes it much easier to explore the menus. Clicking on the left mouse button reveals the full menu in a vertical array, and you can drag and quickly open another page, or click on and access any parameter on the current page. The stenciled, pale-colored guide to the VS-2480 rear-panel connections is a poor design choice because overhead lighting or glare can completely obscure the labeling.

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FIG. 7: Buttons on the Boss BR-1600CD give you direct access to application-specific DSP processes, such as the Vocal Tool Box.

Three buttons on the right-hand side of the Boss BR-1600CD give you quick and direct access to application-specific DSP processes (see Fig. 7). The Vocal Tool Box button calls up parameters for pitch correction and harmonization of audio tracks (and they don't have to be vocal tracks). The Mastering Tool Box opens multiband dynamics and EQ processors, and the Speaker Modeling button lets you audition your project through a variety of different simulated monitor types. I did not have the opportunity, however, to audition that feature through the recommended Roland digital monitors.

Personal Effects

Typically, portable digital studios group their built-in effects in two main configurations. With track-based effects, you can apply them while recording (in which the effects are printed with the performance), or you can apply them to a track (or group of tracks) that has already been recorded. Mastering effects usually appear at the stereo bus of the PDS for a global treatment of the tracks. Dynamics processors and multiband EQ are typical mastering effects.

I particularly like Korg's simplified division of effects into Insert, Final, and Mastering categories. Insert effects can be single or multiple-effect algorithms with a variety of signal-flow configurations such as mono in/stereo out or eight in/eight out. The more complex the configuration is the fewer simultaneous insert effects you can use. In practice, this was never a problem: I simply adjusted the send of each track to the Master effects, which includes fine-sounding reverbs, delays, and less conventional effects such as a ring modulator and talk-box simulator. You can modulate almost all of the effects with an expression pedal, LFOs, or MIDI, which can provide parameter sweeps via Control Change (CC) messages or synchronization with MIDI Clock. Many of the systems here — such as the Boss BR-1600CD, the Roland VS-2480, the Tascam 2488, and the Zoom MRS-1608CD — have similar controls.

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FIG. 8: The Roland VS-2480 holds a wealth of expansion options, including SVGA monitor and mouse operation and—with an expansion board—a hefty selection of popular third-party plug-ins.

From a sonic perspective, the Roland and Boss guitar-oriented effects are at the top of my list. With the optional VS 8F-3 expansion board, the VS-2480 (see Fig. 8) hosts a burgeoning list of Roland and third-party plug-ins, such as Antares Auto-Tune, TC Electronic TCR 3000 Reverb, IK Multimedia T-RackS Analog Modeled Mastering Station, Massenburg Hi-Res EQ, and Universal Audio 1176LN.

Zoom's MRS-8 hosts a remarkable number of great-sounding effects. The chorus and other modulation algorithms are particularly warm sounding, as are the guitar-amp models. Two basic effects-routing schemes break down into multiple effects algorithms. The mic algorithms are titled by application, such as ForBrass, LO-Boost, and the ever-popular FanFan, which simulates the sound of talking into a fan. More importantly, I was pleasantly surprised by a variety of interesting and useful mastering algorithms, primarily multiband dynamics, EQ, spatial enhancers, and a resonant filter. All of the effects are programmable.

Controls for the Fostex MR-8 effects are simple because, apart from send level and reverb-delay time, there are no other parameters to tweak. The MR-8 also has amp and mic-modeling selections, and three preset mastering algorithms, none of which is editable.

Assistant Editors

Regarding editing, a typical PDS gives you fewer editing features than a DAW does. The ability to precisely set markers and location points is especially important when editing on a PDS, and some models make it easier than others. The Akai DPS24 can edit at the single-sample level, and its waveform display zooms in with an equal resolution. When cutting and pasting, imprecisely identified regions will create pops or clicks due to mismatched amplitudes. The Search Zero feature in the Wave display of the Korg D32XD automatically finds the next zero crossing, giving you a seamless edit point. According to Korg, that feature can be used to remove clicks and pops automatically.

One of the great advantages of computer-based digital recording is the ability to shuttle between alternate takes or create a composite track. Almost every PDS has virtual tracks for that purpose, but some manufacturers implement virtual tracks differently.

Portable digital studios typically have between eight and ten virtual tracks for each mono track. Zoom's MRS-8 holds ten virtual tracks for each of its eight regular tracks, and it also holds ten virtual tracks for its stereo master track. The Fostex VF160EX has eight virtual tracks that you can freely divide among the eight regular tracks. The Fostex MR-8 doesn't have virtual tracks, but you can move data between the eight regular tracks and the clipboard with standard cut, copy, and paste operations.

It's surprising how many small items you need to keep track of when you're recording and mixing. You may need to remember exactly where you want an acoustic guitar to come in, or where you need to fix a note that sounds a bit sharp. The Fostex MR-8 has one Locate button each for In and Out locate points. You can store those locations on the fly or with playback turned off, but there is no facility for markers. In contrast, Roland's VS-2480 stores 100 locators that are divided into 10 banks, and each project can hold as many as 1,000 markers. Additionally, the VS-2480 uses a special set of markers for CD-track indexing.

With the exception of the Fostex MR-8, The Tascam DP-01FX, and the Zoom MRS-8, all of the studios in this roundup support at least one of two convenient types of mixing: scene-based and dynamic automation. Scene-based automation is a sequence of mixer-setting snapshots that can abruptly change at different junctures of a project. Dynamic automation gives you linear, continuous mixer moves.

Automated mixing captures the work of many hands changing volume, panning, EQ, dynamics, and effects settings. Scene-based automation is great if there isn't any gain riding or continuous parameter changing required. For continuous tweaking, dynamic modulation is the only choice. Recorders that have dynamic and scene-based automation are convenient because you can use a scene as a starting point and add dynamic mixing after the fact. The Korg D32XD, Roland VS-2480, and Akai DPS24 have scene automation and built-in dynamic automation. (The D1200mkII has built-in scene automation.) Many of the other units, however, have another form of automation of which you may not be aware.

The Secret Life of Altered MIDI

Surprisingly, one of the least promoted aspects of portable digital studio recorders is their ability to send CC messages for virtually every mixer move and parameter change. Once captured in your MIDI sequencer, CC messages can give you the same results as an automated mixdown and allow for detailed, pinpoint editing.

The Roland VS-2480 has V. Fader mode, a control-surface menu that allows you to assign CC messages to the faders and the pan- and aux-send knobs. The list of messages is generous, although not comprehensive, and you must remain in the V. Fader menu because the VS-2480 reverts to its default assignments when you exit.

With some research into the MIDI implementation chart of your PDS and a bit of MIDI mapping, you can turn many of these units into versatile and powerful control surfaces (see “Master Class: All Over the Map” in the August 2003 issue of EM at The Akai DPS24 relies on its built-in dynamic automation, neither transmitting or receiving CC messages.

Mix, Bounce, and Burn

When you're ready to buy a PDS, something that you may want to consider is how you'll create your stereo mix. Despite having features in common, the various models in this roundup handle that process differently. The MRS-8 lets you mix all tracks, including the bass and drum tracks, to a separate Master Track or a pair of virtual tracks. In addition, the Master track has ten virtual tracks, so you can create alternate mixes. The main limitation of the MRS-8 is that although you can mix everything internally, there is no way to convey your mixed project to the outside world except through its analog outputs.

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FIG. 9: The Korg D1200mkII lets you bounce all tracks down to overwrite a stereo pair of normal tracks, and includes the content of the target tracks. You can also bounce to virtual tracks.

Mixing in the Fostex MR-8 is a bit more cumbersome. The last four tracks are stereo pairs, and you can either bounce tracks 1 through 4 to tracks 5 and 6, or bounce the first six tracks to tracks 7 and 8. Although you can fill up all eight tracks, the MR-8 has no internal facility to bounce all the tracks to a stereo pair. You can mix to an external device using the unit's optical S/PDIF port or analog outputs, or you can export the tracks as WAV files to your computer for assembly in a digital audio sequencer.

The Tascam DP-01FX mixes all tracks down to a stereo master track, and the master track is also the conduit for bounces to other stereo pairs. Optical S/PDIF and stereo ¼-inch analog outputs let you record the finished product to another device, or you can export the mix to your computer using the USB port.

With the Korg D1200mkII, you can bounce a final mix to a pair of virtual tracks or overwrite a pair of normal tracks, even if you are using all 12 tracks (see Fig. 9). In the latter case, you'll overwrite any preexisting data, but that data will be included in the mix.

The Korg D32XD, the Korg D1200mkII, the Zoom MRS-1608CD, the Fostex VF160EX, and the Tascam 2488 let you burn your finished product to disc using a built-in CD-RW drive. The Boss BR-1600CD and Roland VS-2480 can bounce tracks to overwrite a stereo pair of tracks. Or, in Mastering Mode, you can mix your full track count through dynamics processors to a pair of virtual tracks.

Station to Station

Despite their remarkable self-sufficiency, even the best of these studios can benefit from the flexible editing options and visual capabilities of computer-based workstations. Almost every PDS discussed here can store and retrieve audio in a standard format — usually WAV or AIFF — and give you some means of transferring audio to a personal computer. The Zoom MRS-8 records directly to CompactFlash cards, which can be used to shuttle data to your computer. Unfortunately, it saves only bundled data, not the 16-bit, 44.1 kHz WAV files that comprise its tracks.

The Fostex MR-8 can use CompactFlash or a USB port to transfer audio. WAV Manager (Mac/Win, free) is a simple application that reads MR-8-format CompactFlash cards for importing and exporting WAV files, and it's available as a download from the Fostex Web site.

Beats in a Box

It's handy to have at least a metronome click for bar-to-bar editing and to stay in the pocket while recording. It's an added bonus when a PDS gives you full-fledged drum tracks. Korg's D- and XD-series studios have plenty of sampled grooves that you can string together into song form or use as a rhythm guide. Because they are sliced into individual hits, the grooves can adapt to practically any tempo.

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FIG. 10: The Zoom MRS-1608CD is the only PDS in this roundup that lets you trigger its built-in drum and bass sounds with an external MIDI controller.

The Zoom MRS-8, the Zoom MRS-1608CD, and the Boss BR-1600CD let you create your own rhythms with a built-in drum, percussion, and bass sound set. The Zoom's Velocity sensitive trigger pads feel surprisingly sturdy, allowing you to sequence patterns, link them together, and then print them to a stereo pair of audio tracks. The MRS-1608CD lets you sequence patterns with an external MIDI controller, something that no other unit discussed in this article would do (see Fig. 10). The MRS-1608CD also has banks of guitar sounds and exotic-sounding loops.

The Tascam 2488 hosts a complete set of GM-compatible instruments (see Fig. 11). I doubt that I would use those in a serious arrangement, but they work just fine as guide instruments that you can replace later with better synths or live musicians. You can import Standard MIDI Files (SMFs) for playback through a USB connection to your computer, but the unit has no facility for sequencing with an external controller. You can link the unit's built-in drum and percussion patterns to create a rhythm sequence, and the 2488's Pattern Arrange screen displays all of the information that you need to lay out a song from beginning to end. You can edit the length of individual patterns and insert tempo changes for each selected pattern. Nonetheless, that method of creating a rhythm track is counterintuitive and less than inspirational.

With the Tascam 2488, you'll need to edit MIDI files before importing them. The built-in tone generator, however, has basic editing features, including a selection of GM instrument banks and programs. In a nice touch, the GM instrument effects are independent of other recorder DSP. That means that you can audition files without allocating DSP resources or wasting time routing them to the MIDI tracks.

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FIG. 11: The Tascam 2488 holds 24 tracks of audio and 8 tracks of simultaneous recording regardless of bit-depth settings. It also has a complete GM-compatible synth.

A wonderful collection of drum loops from Discrete Drums is supplied with the Roland VS-2480 and the Boss BR-1600CD. The BR-1600CD also has a built-in drum and bass sequencer, plenty of preset grooves to string together, and user memory to store your own patterns. The Zoom and Roland drum kits sound great and are expressive, but triggering a bass using the pads doesn't give you the same playing dimensionality that you get from a keyboard that has pitch bend and modulation capabilities.


Although the units discussed here have more in common than is readily apparent, I found a grab bag of surprises in many of the units. The Boss BR-1600CD can trigger and sequence banks of loops with drum-machine-style pads, and it can read WAV files directly from commercial CD-ROMs, giving you access to third-party loops. The BR-1600CD also will automatically time-stretch imported drum loops to match the tempo of your song.

Using cursors, wheels, and buttons to name tracks, songs, and files is a time-consuming and awkward process. The Akai DPS24 and the Roland VS-2480 get kudos for supporting the use of an ASCII keyboard.

The Akai DPS24 sports direct inputs to its A/D converters, allowing you to skip the internal preamps and avoid gain-staging problems when using an external mic preamp. The Tascam 2488 has traditional vari-speed and SSA (Slow Speed Audition), which lets you rehearse parts at slower speeds without changing the pitch of the material.

The Zoom MRS-1608CD and the Boss BR-1600CD have the ability to generate 3-part audio harmonies based on chord data that you supply from the built-in rhythm section sequencer. On the more pragmatic side, if you want to tune your playback system's frequency balance to work with your room, the Roland VS-2480 has an oscillator that can generate white or pink noise. Just set up a mic and feed the oscillator back to the VS-2480's built-in frequency analyzer, which has a Fast Fourier Transform display.

They may be endowed with fewer features than their more expensive siblings, but keep in mind that the Zoom MRS-8 and the Fostex MR-8 are nearly as portable as you can get while keeping a full-format size. In addition to being small, they can be battery powered. Both recorders store data on CompactFlash cards rather than comparatively fragile built-in hard drives, making them a bit more robust and therefore better candidates for recording on the go.

Rev Up

One criticism leveled at the PDS category overall is that the devices are closed systems that can't be significantly upgraded or expanded. Some of the units discussed here, however, have undergone several significant upgrades in software and hardware. For instance, version 2.0 of the Korg D32XD operating system increases the record and playback track count in 24-bit mode, adds new navigational tools, and adds the ability to load files from other Korg recorders as far back as the D12. In many cases, you can visit a manufacturer's Web site to obtain more recent updates than the ones that come with the unit. You typically update a PDS by installing files from a CD or uploading them from a connected USB port.

The development of ak.Sys TrackView software (Win) allows the Akai DPS24 to have computer-and-mouse navigation with the benefits of your computer's display. Features include a meter-bridge display of tracks, groups, inputs, sends, and returns, as well as scrolling waveform displays. A huge benefit is the ability to color-code tracks, which makes it easier to see edit regions and playback or record status.

You can use a QWERTY keyboard or a mouse with the ak.Sys TrackView software to remotely run the Akai DPS24 transport; enter names; and perform standard track copy, cut, and paste operations. You can also import and export WAV and AIFF files, back up projects, and update the DPS24's operating system. Unfortunately, the TrackView features are not available for the Mac. That confuses the issue somewhat, because the bundled CD-ROM contains ak.Sys software that runs in Mac OS 9 for other Akai products. You can, however, download ak.Sys Server software for Mac OS X, a simple utility that gives you file import and export and OS upgrade capabilities for the DPS24.

Down at the Docs

Despite tremendous user interface advancements, documentation that is organized, clear, and concise is essential to getting the most out of a PDS. Sadly, despite all of the advances in functionality, lucid and well-organized manuals are still the final frontier. On the positive side, Korg, Tascam, and Zoom took extra pains to make their systems easier to comprehend.

The main Akai DPS24 manual, however, is badly in need of an update and an expanded index. The main manual has no information on the ak.Sys networking software. Instead, there are a handful of separate update guides, making it difficult and confusing to find the information that you need. Overall, the DPS24 manual would benefit greatly from an integrated rewrite.

Roland's VS-2480 has a slew of addendums, but they are much better organized than Akai's. Some instructions for the Fostex VF160EX are so needlessly convoluted and incomprehensible that you'll probably reach for an aspirin while trying to figure them out.

Trends and Wish Lists

Because of the evolution of the PDS since EM's last survey, it's tempting to speculate on future developments. In this day of high-resolution audio and huge file sizes, it is foreseeable that portable digital studios make the move from built-in CD-RW drives to built-in DVD writers. Additionally, having FireWire connectivity would allow you to quickly and conveniently backup recorder data to high-capacity hard disks.

Although Tascam's 2488 built-in synth, SMF support, and backing tracks are terrific resources, the inclusion of sequencing or real-time triggering of internal sounds would extend the studio-in-a-box concept even further. With the availability of plug-in expansion boards, the inclusion of a full-featured software synthesizer in a PDS can't be far behind.

If a manufacturer combined built-in sequencing, a software sampler, and an analog-modeling synth, and I'll bet the personal studio community will beat a path to its door. Whatever the future holds for portable multitrack recording, now is the best time to jump in.

During the commission of this story, Marty Cutler harbored up to 220 tracks (not counting virtual tracks or his own PDS) of portable digital studio, depending on sample rate and bit depth. He is still trying to calculate the total number of Undo levels.


To see a table showing Portable Digital Studio Specifications click here

To see more Portable Digital Studio Specifications click here