Korg D16

With their new 16‑track portable digital multitracker, Korg have packed a lot of features into a surprisingly small case.

As the foxy French lady with the tape measure in the car commercial doesn't quite say, with digital recording technology — as with so much in life — size matters. Few recording musicians would dispute, for example, that 16 tracks of hard‑disk recording are better than eight. Nor that a recording setup that occupies only a few square inches is usually more convenient than one that devours half your studio space like the alien vegetation from Little Shop of Horrors.

Korg's new D16 HD multitracker, then, is doing well even before it leaves its box, being big in one respect (track numbers) and small in the other (physical size). It's relatively rare to find a project‑studio‑priced digital 16‑track, and even more rare to find one that's also incredibly portable, despite having a 24‑channel mixer section and internal 2.1Gb hard drive. Indeed, setting aside computer‑based systems, the only direct 16‑track competition for the D16 seems to be Roland's less compact VS1680.

More points are scored for the D16 by what looks like a very nice spec: uncompressed 16‑bit recording, a mode offering 24‑bit audio (albeit with only eight tracks), 3‑band EQ, generous programmable effects including Insert, global and 'Final' treatments, scene‑type mix automation, direct CD burning to a CD‑R/CD‑RW drive, a touchscreen, over 200 built‑in rhythm patterns, and seven virtual tracks per 'real' track, to expand possibilities during recording and mixing. Sounds almost too good to be true...

Look In

It hardly seems possible that so many facilities could be squeezed into such a compact frame. Amazingly, the D16 is marginally smaller than its 8‑track forebear, the D8 (reviewed SOS April 1998), and has a slightly different appearance, attractive in a chunky, workmanlike way, and not unduly crowded or confusing in terms of control layout. An internal PSU rather than a line‑lump would be nice, but presumably this would make the D16 less portable and more expensive.

The D16, like Korg's Trinity and Triton workstation keyboards, uses a well‑designed touchscreen. Here it is showing (from top) the main Song window, meter display, and track view display.

The left two‑thirds of the front panel hosts the generous 5x1.5‑inch backlit touchscreen which is central to the D16's functions. Though touch‑activation might seem like a gimmick, in practice it's extremely useful and intuitive, though much that can be done by prodding the screen can also be accomplished via front‑panel controls. Beneath the screen are 12 white‑capped 50mm‑throw faders, which control up to 16 channels of audio, in a combination of eight mono and four stereo channels. Above each fader is a neat pan pot and a Track Status key that toggles between channel off/on/monitor analogue input/record ready, and also behaves as a track mute switch. The set is completed by a red‑capped Master fader.

The remaining third of the panel is peppered with squidgy buttons, many of which access recorder‑specific functions. There's a conventional recorder transport section, naturally, and also a set of keys that call up mixer configuration screens in the display, including a metering screen. There's little physical metering on the D16, save level LEDs for four of its inputs.

Most of the D16's interfacing is located at the rear, including four of its analogue inputs, with gain controls, S/PDIF optical digital I/O, analogue master out, monitor out (with level knob), MIDI In and Out, an aux send socket, and a SCSI2 connector. Four more analogue inputs are sited at the front edge, along with their trim controls. Input one in this area is particularly well specified, offering a choice of guitar, XLR or balanced jack inputs; input two offers XLR and balanced jack (using the widespread combi‑jack format), and the rest of the inputs are balanced jacks. Only headphone, footswitch and expression‑pedal sockets remain.

Korg D16 rear panel socketry.

One of few significant omissions from the D16, in our opinion, is phantom power. Quality condenser mics requiring it are now very affordable, and surely anyone investing in 16‑track digital will want to use one. They'll have to budget for an external phantom supply (quite cheap, in fairness) or mic preamp if they choose the D16.

Bearing in mind the growing popularity of the ADAT and TDIF multitrack digital formats, it may also surprise some that the D16 has no ADAT or TDIF interfacing. The fact that Korg have used all‑analogue inputs rather than, say, an ADAT interface and some analogue has up and down sides. On one hand there's no ADAT interface sitting there useless if you've no compatible gear, but on the other there's no straightforward means of getting audio out in multitrack form, integrating the D16 into more sophisticated digital systems, or mixing in audio from ADAT‑ or TDIF‑compatible sources. Korg could, perhaps, have made the optical S/PDIF a switchable ADAT connector, as some other products do, but there's obviously a cost implication. An ADAT option would have been nice, though.

The Mixer

The D16's mixer offers 24 channels. A full range of facilities is available to the 16 channels used by the 16 audio tracks, although tracks 9‑16 are arranged as stereo pairs and the audio assigned to these tracks is mixed by stereo channels. The remaining eight channels organise the analogue inputs as a submixer during a mixdown, routing audio, with level and balance control, from the inputs to the stereo mix output. This facility is probably designed to allow sequencer‑driven instruments to be mixed alongside D16 audio tracks. However, the 'sub‑mixer' arranges the eight inputs as four stereo pairs rather than eight discrete channels. This is ideal for mixing in a handful of stereo synths or samplers (or patching in a real submixer if you have more synths than D16 inputs), but means that any external monophonic sound sources wastefully still use up one stereo pair. On the up side, submixed external audio can be processed with the 'Final' mastering effect (but not the other effects, or EQ) alongside on‑disk audio, and may be included in a bounce to stereo. There is a way of using global and Insert effects on external audio, but only as part of a special '14+2' bounce mode, where audio from two inputs takes the place of two tracks of disk audio and has access to their channels' facilities.

Korg's literature describes the mixer as a 24‑input, 8‑bus device, but the latter assertion is perhaps correct only inasmuch as eight inputs can be freely assigned to any eight audio tracks, and recorded. It's even possible to route one input to all eight tracks simultaneously, if you should want to! However, there's no real internal busing, save when audio tracks are being bounced to mono or stereo, and in this case the bounce level is set with the channel faders and the master fader — there are no bus/subgroup faders or level controls.

That said, buses or subgroups as we know them aren't missed during normal operation. Only if you wanted to, say, mike up a drum kit and premix it to stereo would the D16 come up short. In this case, though, you could cover the drums with up to eight mics (provided you had six extra mic preamps), record the performance and then bounce it into stereo. Save the original recordings as virtual tracks and you could even remix the drums later, if desired.

To return to the main mixer channels, these are well‑specified, and would take up quite a bit of desk real‑estate if built as hardware. Apart from a physical fader and pan pot, each input features 3‑band EQ (with sweep mid), phase reverse, access to up to eight on‑board Insert effects, sends to two onboard global effects, and a single auxiliary send for accessing external effects.

The D16's mixer section.

Much of the mix action takes place on‑screen. Routing analogue inputs to audio tracks is done on the Input display, summoned by pressing the relevant button. The EQ/Phase, Insert Effects and Master/Final Effects windows are also accessed by dedicated buttons, as are the Solo/Monitor display (which allows you to solo tracks and effects sends/returns, and route audio to monitor and headphones outputs) and Meter/Track View display. The last provides comprehensive bargraph metering, with user‑definable peak hold, for all audio tracks (pre‑ or post‑fader), the two internal effects sends, and monitor and stereo master outputs. The useful Track View option shows, in miniature piano‑roll format against a scrolling timeline, which tracks contain audio data and where it is.

All these mix displays are clear and to the point. Korg workstation users will find their approach familiar in some ways, including the use of tabs across the bottom of displays for choosing banks of parameters that won't fit on one screen. As an example, 16 channels of virtual knobs for the 3‑band EQ can't be viewed simultaneously, but are selected in three 4‑track banks. While we're on the subject of EQ, Korg offer a high band fixed at 10kHz, a low one at 100Hz, and a mid variable between 100Hz and 20kHz, all with 15dB cut or boost, in 0.5dB steps. It's not the most sophisticated of equalisers, but for beefing up bass, brightening up the top end and helping to rid a mix of any muddiness it's all you'd need. If requirements are more demanding, there are parametrics in the effects selection.

Both EQ and Insert effects can be utilised during tracking, so we won't bemoan the D16's lack of physical insert points. You can't plug in a favourite outboard compressor, but any onboard processes and effects available as Insert Effects to a recorded audio track — including compression and limiting — can also be used on audio as it's being recorded. The lack of insert points at the stereo master end of the signal path is often a cause for concern with digital desks and multitrackers, too, since if there's no insert it may not be easy to compress the stereo mix before mastering. What Korg offer for this purpose is that dedicated 'Final' onboard stereo processor, offering several dynamics options.

Before we leave the mixer, we should mention automation, which is pretty much expected of digital multitrackers worth their salt these days. The D16 features Scene automation, which is easily set up, with a maximum 100 Scenes per song. Each nameable Scene memorises the complete state of the virtual mixer, including effects and EQ settings, external aux send status, pan/balance, and level. Scenes can be recalled manually, against time locations within a Song (a feature which is particularly useful and well implemented), or with MIDI program changes. Sadly, there's no crossfading between Scenes; it would be nice if Korg could add this in an update. D16 controls, whether physical or on‑screen, don't transmit MIDI data, so there's no potential for dynamic automation with a sequencer, either. Some will miss the ability to automate complicated dynamic effect, pan and level changes in this way.

Tracks & Time

The D16 records 16 tracks of 44.1kHz audio, plus a potential seven 'virtual' tracks per real track, to its 2.1Gb hard drive (apparently a robust laptop‑type device) or an external SCSI drive. Incoming audio at different sample rates is automatically converted at the input to 44.1kHz, which saves you having to think about it. The supplied drive yields 6.5 track hours of 16‑bit audio (less for 24‑bit), which is around 25 minutes of continuous 16‑track recording. Time is allocated dynamically, so any space unused on one track is available for other tracks.

It's wonderful to have 16 tracks when you're used to 8‑track digital recorders — you can go so much further before having to make bouncing decisions. However, if it hasn't become clear to you already we should point out that though the D16's recorder does offer 16 tracks, they're not all completely independent. As mentioned elsewhere, the arrangement is eight mono tracks and four stereo tracks. You can record to one half of a stereo pair independently of the other, but each track in the pair will be hard panned left or right and treated with the same EQ and effects as its partner. Obviously, this is a restriction of sorts, and it would be better if all 16 tracks were independent mono. (Perhaps the method chosen made DSP savings for Korg, since the two tracks of each stereo pair don't each need a complete mixer channel of facilities.)

All is not lost, however. The stereo pairs are fine for recording synths and samplers, for those not running synchronised sequencer parts, and there's another very good use of the track arrangement: fill up the eight mono tracks, bounce these to a stereo pair, then go back and fill the eight mono tracks again, bouncing them to another stereo pair, and so on. You could, for example, build up a sophisticated 40‑track arrangement easily in this very tidy, organised fashion. The original mono tracks needn't be lost after bounces, either, as they can be filed away as virtual tracks.

It's also worth noting that the D16 lets you fill up all 16 tracks and still bounce them to stereo. This is done by bouncing to virtual tracks, so at least two must be empty. You can even record direct to a virtual track without first recording to a 'real' track and then exchanging it with a virtual track, as some digital multitracks force you to do.

Recording & Editing

The first step in recording to the D16 is creating and naming a Song, and choosing 16‑ or 24‑bit. Up to 100 Songs can go on one disk, but it's unlikely you'd fit this many, unless they were short jingles or the maximum allowable 1000Gb drive was attached! There seems to be no limit on individual Song length, other than available HD space.

Next, you might well want a metronome to play to. The D16's thinks it's a drum machine: as well as a standard click, 215 rhythm patterns played by sampled drum sounds are available, with various intro, verse and fill options. Pattern chaining is possible via an editable tempo map, so this part of the D16 could actually be used as a preset drum machine, and patterns can be routed to audio tracks for recording. They're arranged into styles — covering rock, funk, jazz, hip‑hop, reggae, techno, Latin, jungle, and so on — and though they're not editable and the sound palette across patterns is very similar, their quality is pretty good. Certainly, in many circumstances they'll give a better feeling than playing to a basic click, especially since the metronome suffers from practically inaudible downbeat accenting. However, note that although the metronome is capable of odd time signatures (anything from 1/4 to 16/16), the rhythm patterns are only available for 3/4, 4/4 and 6/8 signatures. Choose something unusual and only a click or hi‑hat will play.

Actually recording audio is straightforward, and both manual (button or footswitch activated) and auto punch‑in/out are available if a bit needs redoing. For on‑the‑fly, manual use, multiple punch‑ins and ‑outs can be performed without stopping the D16; alternatively, if you prefer to program drop‑ins in advance, punch points can be set precisely and quite easily, and results are seamless. For the benefit of anyone recording their own playing without assistance, Korg have also implemented a sampler‑like Trigger record mode, which waits until audio input reaches a user‑settable threshold and initiates recording, with a pre‑Trigger option to ensure no wanted audio goes unrecorded. Another useful mode is Loop Record, which is rather like the feature in Cubase or Logic that allows multiple takes to be recorded in succession and stacked for auditioning. With the D16, you can record up to 99 takes and pick your favourite afterwards. Moving around a Song is quite easy too: each can have four locate points, with dedicated buttons, and 100 nameable 'Mark' points, accessible from their own screen. The main difference between the two is that jumping to a locate point does so without stopping play (there is a small gap, though), whilst jumping to a Mark point does stop playback

Audio editing is flexible and quite fast, and there's a Scrub function, for finding exact edit points, that offers half‑speed playback — the only thing remotely like varispeed on the D16. You can view a smallish graphic waveform in the display too, which helps during editing. Editing is not 'playlist'‑style, where the recorder notes the position of audio to be copied and references it: data is actually copied, using disk space. Tracks can be copied once or multiple times, as can sections of audio, one track at a time or across groups of tracks. Blank space can be inserted into tracks, bumping subsequent audio forward — it's then possible to paste audio into the blank space — and tracks can be swapped, reversed, and expanded/compressed, the last being basically time‑stretching. The required amount of time‑stretching is set by defining the section of audio to be stretched and the space (in bars or beats, for example) the processed result should occupy. There are fast, middle and best‑quality options, and a time‑stretch can be performed with or without pitch‑shift. Oddly, there's no dedicated pitch‑shift function. The results achievable with expand/compress are variable, though for minor fixes, such as shortening a loop that's a little too long, it's absolutely fine. Trying to fit a vocal into double or half its original space introduces artefacts, but it's doubtful you'd be trying to do something this extreme.

Recorded data can, naturally, be erased (removing the audio, leaving silence) and deleted (removing the audio and the space it occupied). An Optimise function takes tracks composed of many sections of audio, which could cause playback problems for the hard disk, and rewrites them to a contiguous audio file. One D16 editing capability that should be applauded is transferring of tracks between Songs, since the Clipboard is shared by all Songs on a disk. This makes it possible to easily repurpose personal material in different arrangements, or even assemble a library of loops, hits and sound effects available to all your Songs, just as you can with a sampler. It's a seemingly simple ability that's beyond some other digital multitracks on the market!

Effects

Whereas the D8's effects section, based around the simple Pandora guitar processor, was seen as somewhat perfunctory in the SOS review, the D16's is much more comprehensive, and rather generous for a multitracker, feeling something like the effects from the deluxe Trinity or Triton workstations. Treatments are editable in reasonable depth, with up to 16 tweakable parameters. Reverbs, for example, offer decay time, pre‑delay, HF damping and high and low EQ level. In terms of quality, D16 effects are very pleasing, and we found presets, with minimal tweaking, produced smooth, non‑obtrusive results. Compressors lack a ratio control, but there's one available with the limiter effect, which seems more like what one would normally expect from a compressor and works very well.

As touched upon earlier, up to eight Insert effects are available, applicable one to a track. Insert effects come in four flavours:

• 1‑in/1‑out: simple mono effects, eight of which can be used at one time, comprising compressor, limiter, overdrive, parametric 4‑band EQ, phaser, multitap delay, amp simulator, gate, expander, and chorus/flanger.
• 1‑in/1‑out with two‑effect chain: up to four of

these can be used simultaneously and they include compressor‑amp simulation, exciter‑multitap delay, reverb‑gate, and mic simulator‑limiter, plus many other combinations.

• 2‑in/2‑out: two of these more complex effects, mainly big stereo treatments, can be used at once. Seven reverbs, six delays, seven modulation effects, seven dynamics processors (including a multi‑band limiter), plus sundry special effects, are available. The last group includes ring modulator, doppler, analogue record (which adds hiss and crackle), talking modulator, vocoder, rotary speaker, and pitch‑shift.
• 1‑in/2‑out: these effects are available only to audio arriving at a D16 input, not to already‑recorded audio, and two can be used at a time. Chains of up to five treatments (which have a stereo output, for recording to two audio tracks) are optimised for DIing instruments and mics, with various options for axe‑freaks (such as distortion‑noise reduction‑amp simulation‑cabinet resonance‑delay), and three bass DI chains. There are even a couple for vocals — though you wouldn't usually want to record a lead vocal in stereo.

In normal circumstances it's not possible to use Insert effects on incoming audio and disk playback tracks at the same time (the exception is during the '14+2' bounce mentioned earlier). If Inserts are configured for processing incoming audio, to compress a vocal, say, playback Insert usage is disabled. This is not the end of the world, despite the fact that you won't hear Insert treatments applied to the other tracks while you're recording the vocal. However, when the vocal is recorded and you change back to playback Insert usage, all is reset and the Insert treatments you've defined are not retained, so will have to be recalled and reassigned. Any edits to Insert effects will have been lost too, unless you saved them. One way around the problem is to save everything as a Scene before changing Insert effect usage and recall the Scene after recording is finished. However, it would be better if the user didn't have to think about doing this.

The effects story doesn't end with Inserts. Two global processors (dubbed 'Master') are also available, on an internal send‑return loop. Their algorithms include 15 reverbs, six delays, seven modulation effects (stereo chorus, flanger, vibrato, and so on), and four special effects (stereo ring modulator, doppler, analogue record and talking modulator). These effects are accessed by the two aux sends available to all mixer channels, and there are return level and balance controls to alter their level in the mix.

The icing on the cake is the Final (or mastering) effect. Though there are fewer algorithms available to this processor it's one of the nicest features of the D16. Dynamics are represented by a stereo compressor, limiter, gate and multiband limiter, but the collection also includes stereo parametric 4‑band EQ, graphic 7‑band EQ, and reverbs and delays. No routing is involved, as the Final effect is always patched into the stereo output: it's simply turned on if you need it.

All the effect types have their own factory and user memory locations: 128 of each for Insert effects, and 32 of each for both Master (global) and Final effects. The latter figure doesn't seem over‑generous, especially given that user memories can't be dumped via MIDI; in mitigation, effect changes and tweaks can be saved as part of a Scene, though if the tweaked effect is based on one in a User memory which is changed later, the tweaked effect would be changed too. If you always make your edits from Factory settings, the situation won't arise.

It's perhaps just as well that the D16 has such excellent internal effects potential, since its external effects provision is limited. As mentioned elsewhere, there's just one mono aux send to the outside world, and no dedicated returns, so returning an outboard stereo reverb would require the use of two analogue inputs.

Conclusion

The D16 has a wealth of thoughtful, genuinely useful features, and has been carefully and transparently designed to be pretty much as easy to use as it could be. Great strides have been made since the D8, and the D16 feels like altogether a more serious machine, even though it's so compact. The touchscreen, especially, speeds and simplifies operation, and is so addictive that you begin trying to operate other gear in the same way! The fact that eight tracks can be recorded simultaneously makes the D16 useful for live and band recording, its effects are impressive and come as standard rather than as an option, and its sound quality is beyond reproach.

It's difficult to overstress how amazing it is to have access to 16 tracks of quality digital audio and all this processing in such a compact package. This is a truly portable, all‑in‑one digital studio, and though it's not perfect it appears to offer virtually no insurmountable compromises. Phantom power is missed, and it's true that direct track outs or ADAT interfacing would have allowed D16 multitrack audio to be integrated into a larger system later on. However, with 16 tracks (plus virtual tracks) most people won't grow out of the D16 quickly anyway: it really does provide all you need to produce top‑quality recordings. The project‑studio digital 16‑track market is far from crowded, and we can see musicians flocking to check out Korg's contender and being very excited by what it has to offer.