Korg D32XD & D16XD

Photo: Mark Ewing

In a market populated by 16-track and 24-track machines, Korg up the ante once again with the first project-studio multitracker to offer 32-track playback.

In recent years, the project studio recording paradigm has shifted steadily away from the 'hardware recorder and separate mixer' model and polarised into a mainstream choice between the computer DAW and the all-in-one hardware studio. For those who favour the latter, the maximum track count available has been 24, from the Akai DPS24 and Roland VS2480. Until now, that is...

32 Tracks!

Korg's D32XD is a real heavyweight of a hard disk workstation, with moving-fader automation, touchscreen, built-in 40GB hard drive and CD burner, and extensive onboard processing, able to record up to 16 tracks at once and able to replay up to 32. I use the phrase 'up to', because, as with many such devices, the absolute capability depends on what sample rate and bit depth you're working at. The D32XD offers 16-track recording and 32-track playback at either 44.1kHz or 48kHz sampling rates, with a bit depth of 16 bits, and for the vast majority of contemporary music recording applications this is fine.

Some will complain that 16 bits don't give enough dynamic range, but even allowing a 6dB safety margin when recording you can still expect around 90dB of usable dynamic range. Compare that with the 60dB signal-to-noise ratio of a typical home studio (if you're lucky), and you can see that it's not normally an issue in practice.

Used at the same sample rates, but with a 24-bit depth, the record/playback capabilities are halved to eight-track record and 16-track playback, and if you choose to work at 24-bit and 96kHz, which you can do on this machine, you can record four simultaneous tracks and play back eight. The number of simultaneously recordable audio tracks is further reduced when you punch in across several tracks at once — typically you can punch in across half of the normally available simultaneous record tracks.

Unlike a tape machine, however, each track has a further eight virtual tracks for storing alternate takes, and you don't need to budget for a mastering recorder, because the Korg D32XD has a dedicated stereo master track for mixing onto, after which the final product can be burned to CD-R. The integral CD-R may also be used for storing mix data or for installing OS updates, and you can also record audio tracks from the CD into the D32XD via the track routing system.

To maintain compatibility with other professional equipment, the eight analogue inputs are balanced, with a choice of jack or XLR (mic level). One input is also provided for use with electric guitars and basses, and this feeds via the channel one signal path. A further eight balanced line inputs may be added with an optional AIB8 card, and you can also add an eight-channel digital ADAT I/O expander in the form of the DIB8 card. This also adds word-clock I/O and supports either 44.1kHz or 48kHz sample rates at both 16-bit and 24-bit resolution. The ADAT port doesn't support 96kHz operation.

Most hardware DAWs include some dynamics processing, but the Korg D32XD is slightly unusual in that it also comes with eight analogue compressors that may be used to process the analogue inputs prior to A-D conversion. If the AIB8 analogue expansion board is fitted, this too may be upgraded to include eight compressors via an ACB8 expansion board.

Mixer Section

The mixer section of the Korg D32XD is a pretty serious affair, with a total of 56 input channels, 14 busses and independent EQ paths for recording and playback, so you can't accidentally process a track with the same EQ on playback as you applied while recording. The main mixer channels each have fully parametric four-band equalisation, while the Submixer channels (for processing live inputs while mixing) have two-band shelving EQ. Eight bands of parametric EQ are available on the output for mix shaping, so it is possible to do your own mastering entirely within the D32XD.

Both snapshot and dynamic automation are possible, where a Scene stores the instantaneous fader, EQ, pan and effects settings of the whole mixer. Up to 100 Scenes may be stored, after which they can be recalled manually or via MIDI. MIDI may also be used to control key mixer parameters such as pan and fader values. Scenes may also be set to change under control of the onboard automation system at specific points within a Song (the D32XD's project file). Parameters such as fader moves, aux sends and pans may be recorded in real time, and you can automate both Scene changes and dynamic moves within the same Song if required.

The mixer controls are based around 17 100mm motorised faders, one of which controls the main stereo mix level. The 16 channel faders can be switched as banks to control the 32 mixer channels relating to the recorder section. Each fader has a touch-sensitive cap so that the mixer knows when you want to start writing new mix data, and whenever a new mixer Scene is recalled the faders move automatically so that their positions correspond with the stored values.

Over the years, Korg have acquired a lot of expertise in effects and signal processing, both conventionally and through the use of modelling. In the D32XD, Korg use their proprietary REMS modelling system for where modelled effects are required, and all the effects may be controlled directly using four rotary controls below the display. As well as the more usual studio effects, the Korg D32XD offers tube preamp emulation, guitar amp and speaker modelling, and even microphone simulation.

The effects section boasts 56-bit internal processing, and in addition to up to 24 insert effects, there are also two so-called Master effects (fed from sends) and one Final effect used for processing the whole stereo mix. The effects themselves are based on 52 discrete algorithms for single or combination effects, and there are 128 factory presets as well as 128 user memories for new effect settings or for saving tweaked presets. Effect parameters may also be controlled using an external hardware MIDI controller. The D32XD includes a variable-tempo rhythm pattern generator that provides a far more practical and musical alternative to a metronome.

As you would expect from a modern digital workstation, the Korg D32XD can punch in and out automatically, as well as providing fairly comprehensive editing (cut, copy, paste, move, insert and reverse functions) and 16 levels of undo should everything go horribly wrong! There are also some more sophisticated editing options such as time compression/expansion for tempo matching and waveform normalisation to bring under-recorded tracks up to maximum level. Each Song can have up to 100 marker points placed within it, all of which may be named, and it's also possible to store up to six auto-locate points per Song for keeping track of edit points or specific Song sections.

Touchscreen Control

The operational hub of the D32XD is its touchscreen display — touch any on-screen parameter and immediately adjust it with the main data wheel. Adjacent to the LCD is a set of assignable controls which adjusts the currently selected channel, while below it are four 'soft' knobs which allow you to alter four of the effects parameters simultaneously.Photo: Mark EwingOne of the less common features of the D32XD is the use of a 320 x 240-pixel touchscreen, which helps make the operation more intuitive. While you don't see the same kind of arrangement display as on a computer DAW, you do have the option of a display page that shows which tracks have been recorded onto and where the recorded sections are. A nice touch is that the touchscreen can tilt up at various angles and there's a contrast adjustment knob right alongside.

It's probably fair to say that the D32XD follows the digital mixer paradigm established by Yamaha in most key respects. As standard, a blanking plate is fitted where you see the second set of eight inputs in the photograph — our model had the AIB8 card fitted as well as the ADAT I/O board around the back. My first impression was that the layout was friendly rather than intimidating, with a manageable number of buttons, clear labelling and very limited use of multi-function buttons. The eight mic inputs and the first eight line inputs are built into the top panel for easy access, so you won't be needing a patchbay, and the second group of eight inputs (when the AIB8 card is fitted) sit right alongside.

The main display on both machines can be angled for optimum viewing.Photo: Mark EwingEach physical input has a gain trim knob and a 26dB Pad switch — phase can be inverted via a screen page. Other than the 100mm faders, the only other dedicated channel controls are a Channel Select button, a Channel On/Solo button and a Record/Play status button. A further knob for controlling the monitor output level is situated at the top of the panel to the right of the XLR mic inputs. Three further buttons select which bank of channels are being addressed via the faders (illuminated numerical panels make this very clear), switch the Ch On/Solo buttons between On and Solo operation, and access the Master Track status, which can be Play, Record or Mute. This Master track is used for recording stereo mixes prior to burning a CD-R.

The screen pod includes a few important controls, including four software assignable knobs below the screen for parameter editing, pan and aux controls for whichever track is currently selected (there are buttons for two internal sends and four external sends, the latter feeding balanced jack outputs on the rear panel), and EQ controls. Four buttons select which EQ band is active and then adjustments are made using dedicated Gain, Frequency and Q knobs. A final button labelled Meter brings up a screen that monitors the track audio levels and shows where audio events are present on the track display. There's also a Fader View page giving an overview of fader and pan positions, and this opens automatically when the pan control is adjusted.

Master Section

Most of the master section is given over to buttons, the obvious exception being the now obligatory data-entry wheel, which is accompanied by four cursor buttons, Plus and Minus buttons (that can be used instead of the data wheel for adjusting values incrementally), and an Enter key. Right at the bottom is a sensibly chunky set of illuminated transport controls, complete with a protective surround to the Record button to help prevent accidental operation. Holding Stop and pressing Rewind returns the Song to the start.

Above the transport keys is a pair of left/right Mark Jump buttons used to step through any stored marker positions, and there's also a Record Mode button with three illuminated status panels denoting Loop, Trigger or Auto Punch. The Trigger mode provides a means of starting the recording automatically when the input signal exceeds a set threshold level.

The next panel up deals with markers, locator functions and Scene storing. The Mark key allows up to 100 markers to be created per Song and is also used for renaming and deleting them. Alongside this panel is a Scrub key, which accesses the Scrub page, after which the data wheel may be used to control whatever function you select within that page.

All the automation functions are addressed via the topmost button group, which sits just below the display pod. Most of these buttons relate to display pages, so that you can directly select Channel View, Mixer, Effect, System, MIDI/Sync, Tempo, Song or Track, without having to first scroll through menus. The vital Undo key allows operations to be undone or redone, and, as touched upon earlier, you can perform up to 16 levels of undo. A CD button addresses the internal CD drive's play and record functions.

Once power has been applied to the rear panel and the unit switched on, the Standby switch on the front panel must also be turned on before the unit becomes active. Switching off should also be done via the Standby switch (holding this down brings up a suitable powering-down dialogue box), as turning off at the mains could lose data.

Rear Panel

Most of the remaining connections are to be found on the rear panel, though the guitar input, phones outputs (there are two), the expression pedal jack and the footswitch jack are located on the front edge of the machine, along with two sets of headphone level controls. The CD burner tray is also on the front edge of the machine at the far right-hand side. Various effect parameters may be controlled in real time via MIDI or an expression pedal, though this facility is not available when working at 96kHz.

Korg D32XD rear panel.Photo: Mark Ewing

Although most of the main audio and control connections appear on the rear panel (above), instrument, footswitch and headphone connections are located more conveniently on the front edge of the unit.Photo: Mark EwingThe rear panel is fairly sparsely populated, with the usual IEC connector, power switch and cooling fan outlet on the left (looking from the rear of the unit) and the DIB8 ADAT I/O expansion panel in the centre. Although the fan and drive are quieter than on many computers, I still felt they were far louder than necessary, and the noise could be a problem when recording sensitive vocals or acoustic instrument parts in the same room.

To the right of this panel are a USB connector for data transfer to a Mac or PC, MIDI In and Out connectors, and S/PDIF digital I/O on optical connectors only. Again this seems an odd choice, as coaxial S/PDIF seems to be the most widely supported format for project-studio equipment. However, optical connections do help avoid ground-loop problems. Note that there's no sample-rate conversion, so the incoming sample rate must match the sample rate of the Song, and all the necessary clock sync provisions must be made — which normally means clocking from the external source if there is one, or locking to word clock (only possible when the DIB8 ADAT card is fitted).

Phantom power may be selected independently for each channel, though the warning in the manual is a little over-cautious when it says that only capacitor mics may be connected when the phantom power is on. In fact, balanced dynamic mics aren't worried by phantom power, although there's no reason to apply it to them unnecessarily, and many active DI boxes need phantom power. Balanced jack connections are used for the monitor outs, the four aux outs and for the main stereo outs.

Screen Pages

Korg's use of their Touch View touchscreen system is one of the reasons there are relatively few physical controls on this machine. At the top of the display is a strip showing the Song name, the counter or location time, and the current date and time. Directly below this is the page name. Where multiple pages relate to an operation, named tabs appear at the bottom of the screen, and pressing on any visible tab displays that page. Some pages also include edit icons or small graphical images representing faders, knobs and so on.

When you press an icon or control, a border usually surrounds it, so you know which icon is active and any value changes you make using the data wheel are applied to that parameter. A similar thing happens if you press a parameter value such as an effect number — the value is highlighted and any changes you make are applied to the selected value. In fact there are all kinds of things to press, such as buttons for bringing up dialogue boxes, list buttons, scroll bars, enter buttons, and radio buttons that toggle the associated item on or off. You can also press to tick or untick boxes and, in most respects, the touchscreen features do exactly what you'd expect a mouse click to do on a computer. It's all pretty intuitive and provides a fast way to navigate around the functions compared with traditional menus.

The sequence of operation is that you first use one of the dedicated keys on the front panel to get into the area you want, then you use the screen tabs to bring up the specific screen you need. Most functions can be operated via the touchscreen at this level, though it's also possible to move the cursor around the screen using the cursor keys if you prefer. Where the page displays faders, moving the physical fader will update the displayed fader positions.

Effects

The effects system used in the Korg D32XD is pretty flexible, and in addition to the eight analogue compressors on the inputs, you can set up two different internal digital effects on sends, have further processing on the stereo mix and deploy effects on the channel insert points. Just how many effects you can use at one time depends on the type of effect, as some use more DSP than others (the manual relates DSP usage to effect 'sizes' one to eight), and on the sample rate you're working at. In total, there's enough DSP power for 16 'sizes' of effects per routing page (of which there are two) at 44.1kHz or 48kHz, or half that at 96kHz.

Both D32XD and D16XD can have an optional analogue input expansion fitted by the user, with or without a further eight-channel analogue compressor board.Photo: Mark EwingA blanking plate on the rear panels of both machines can be replaced by an optional ADAT card, which not only offers eight channels of digital I/O, but also word-clock facilities.Photo: Mark EwingThe Routing A page shows eight channels of insert effects plus the two master (post-fade send) effects and the Final (mix buss) effect, while the Routing B page shows a further 16 channels of insert effects only. The insert effects can be assigned to any channel. Where a stereo insert effect is assigned to a mono channel, the next channel along is automatically used to provide a stereo signal path, so you can set up a mono-in, stereo-out reverb or similar very easily. Any of the 128 effect presets can be used in any position and, in the case of inserts, you can either dial through the whole list or press Select on the Insert Effects screen to bring up a menu of mono and stereo effect types for direct selection. A 16-bar DSP meter at the side of the screen shows how much of the available power you've used up for the page that you're working on.

As an example, using two send/return reverbs plus a stereo compressor on the stereo output left me with just over half of the Routing A page's DSP resources free for insert effects at 44.1kHz — and then there's always the Routing B page for more inserts. While in some ways I prefer the certainty of Yamaha's system of offering a limited number of effects plus dynamics on every channel, Korg's system is very flexible, as you can use some powerful effects on channel inserts, including guitar amp modelling, mic modelling, rotary speaker simulation and so forth. The downside is that you are responsible for balancing your DSP resources budget! Another point that I think worth making is the fact that, as all the D32XD's effect algorithms can be used in any position, users may be tempted to put processors such as EQ, amp simulation, compression, limiting, and so on in the aux send/return loop, which in most cases will not produce the desired result. It would have been far better in my view to restrict the send/return algorithms to effects, and to have removed any unsuitable processors from the send/return list.

The repertoire of effects covers the whole gamut of reverbs and delays, all the usual modulation effects, dynamics, guitar amp modelling, and a few off-the-wall creative things.The guitar amp modelling includes a model of the Vox AC30 (Vox are now owned by Korg), and I suspect that much of the amp modelling section is a spin-off from their respected Tone Works guitar-modelling product range. Examples of all the other main amp models are also listed, along with radio simulators, ring modulators, filters, and all the expected compressor, expander, gate and limiter programs.

Of course, the analogue compressors, which are in the record signal path, take no DSP power, so you can always use all eight at once, and better still their parameters are stored just like those of the digital effects. These compressors are accessed simply by hitting the Mixer button, then the Analog Comp button, after which the parameters for all eight compressors are visible. Once in this page, all you have to do is touch one of the virtual knobs on screen and then change its value using the data wheel. Tiny analogue-style meters at the top of each channel monitor the gain reduction, and though these have no scale they are much better than having no gain-reduction meter at all. Furthermore, a sensible-sized gain-reduction meter is shown in a panel to the right of the screen, which relates to the compressor on the currently selected channel. Pairs of adjacent compressors may also be linked for stereo operation.

Mixer & Automation

The mixer is used for feeding tracks to the recorder while tracking, and also for mixing recorded tracks, but physical inputs one to eight (one to 16 if the analogue expander card is fitted) may also be used to feed live signals into the Submixer section at mixdown, making it possible to add external MIDI modules and other sound sources to the mix as required. The Submixer levels are controlled from the screen rather than by a separate fader bank, which seems a missed opportunity. If the ADAT card is fitted, this can also be fed into the Submixer, making a total of 24 possible Submixer inputs, each with two-band, variable-frequency EQ, level and panning. The analogue compressors come between the inputs and the A-D converters, so compression may also be used on the guitar input.

The routing system is fairly flexible so that, for example, you can choose which group of eight mixer channels or recorder tracks will be sent to the ADAT output port. Making manual mixer adjustments is very easy and follows the Yamaha paradigm very closely, including the ability to pair channels for stereo control. The same is true for storing and recalling mixer Scenes, which can be named. You can also specify parameters to be disabled for a Scene on a channel-by-channel basis. Functions that can be disabled are Fader, Channel On, Pan, EQ, Eff 1, Eff 2, Aux 1, Aux 2, Aux 3 and Aux 4. It's also possible to specify parameters that will be disabled for all Scenes.

Dynamic automation may be used to record real-time fader movements, Channel On keys, pan position, all the aux sends and expression-pedal/MIDI control of relevant controllable effect parameters. There are two automation writing modes: Overwrite, which replaces any existing automation data from the point recording is started to the point it stops, or Punch Write mode, which replaces the automation data between two specified locators. The automation system drops into read mode (Automation Play) whenever you stop the transport. An illuminated Automation panel on the mixer shows when the automation is active.

As with Yamaha's system, an opening Scene must be created to act as the basis from which the automation will start. The Scene page's Automation tab allows you to select which channels to automate in the current operation by pressing virtual Record buttons. At the bottom of the page are radio buttons that select what types of automation data you wish to record. Again, very familiar. Finally, you press Mode to select whether you want to Overwrite or Punch Write, and in this window you can also set how long the faders and other parameters take to move back to their stored data positions at the stop point, so as to smooth out abrupt changes.

Having armed the automation record mode, automation recording will begin when the Song is played back, and if it doesn't work out you can either overwrite the automation again or hit Undo. An automation event list can be opened to make manual edits (is life really long enough?) if you don't fancy simply redoing the offending part manually. Similarly, you can copy and paste automation data to different locations in the Song, again via the event list.

Starting From Scratch

As the Korg D32XD stores a date and time along with each Song, it's a good idea to enter the correct date and time when you first switch on. The machine comes with a pre-recorded demo Song, which is useful if you want to familiarise yourself with the controls, and it also confirms that your monitor system is correctly connected. But enough of that, we want to record something!

Before you can arm a track and hit record, you have to create a new Song, where you also select the sample rate and bit depth you'd like to work at. The Song will be numbered to follow any previous Songs you have recorded and you can also give your Song a name. The keypad on the touchscreen makes naming a doddle! Once this is done, you can connect your audio sources, after which you need to assign the physical inputs to the mixer and recorder channels — you can assign any physical input to any track. Once the assignment has been made, it's simply a matter of adjusting the record level and then recording. It may be worth setting up your main aux effects first, though, so that you can hear some reverb when recording vocals.

Although the manual is almost 200 pages long, I found getting around the D32XD quite intuitive, and the speed with which the touchscreen lets you move between pages means that even if you do take a wrong turn, you can go back almost as fast as you can think. I particularly like the effect editing page, where up to 16 parameters (the maximum required by any effect I could find) can be displayed at once and where you can either tap a parameter and then adjust it using the data wheel, or simply tap the parameter row you want and then use the four knobs below the screen to adjust all four on-screen parameters in the row. In fact the only thing I didn't really like about the layout was having to share mute and solo functions via a single channel button.

Particularly handy displays are a detailed channel view and a complete miniature overview of the whole 32-channel playback mixer section. As an experiment, I tried to insert an effect from the Routing B page into a mixer channel that already had an insert effect loaded from the Routing A page and found I couldn't, so you clearly aren't allowed to cascade insert effects in the same way you do software plug-ins on a computer.

The D32XD's USB drive partition was instantly recognised under Mac OS X, appearing as another drive icon.Slightly more vexing was the fact that the touch-sensitive faders occasionally failed to recognise that I was touching them. This is no problem if you have slightly damp skin, but I evidently don't! I also tested the ability of the machine to punch in on multiple tracks simultaneously, and at 44.1kHz (where you can record a maximum of 16 tracks at once), I found that I wasn't able to punch-in on more than eight tracks. If you try for more, a dialogue box appears telling you that you are out of luck. Admittedly you don't often need to punch in more than eight tracks at a time, so this shouldn't normally be a problem, but the number will reduce further at 24-bit, and again at 96kHz.

Sonically I have no problem with the machine, even in basic 16-bit mode, and the quality of the effects is generally very good, especially the reverbs. The guitar amp modelling is also quite impressive, though I found my Parker Nightfly sounded a little thin through it unless I made significant EQ changes. How well you like the models depends on your playing style and expectations, but I found them comparable with many of the modelling processors on the market, and they respond quite well to playing dynamics. Combining analogue compression with an amp model also works well for some guitar sounds, and lets you get the necessary sustain with less overdrive.

Editing is as good as on any other hardware DAW I've tried, at least those without screens and mice, but the whole procedure still feels somewhat cumbersome after having got used to working on a computer. I checked out the USB computer transfer routine using a Mac running OS X, and the Korg's PC partition was recognised immediately as a regular external drive. I converted an existing stereo file to WAV format, copied it into the Korg's folder and then ran the import routine, which places the file at the start of whichever track or track pair you designate. This worked faultlessly. Similarly, any files created on the D32XD and then placed in the PC partition became visible from the computer and could be copied easily.

More Of Everything?

The D32XD is generally well thought out, and it's easier to use than most hardware DAWs, partly due to the excellent touchscreen, though you'll need to satisfy yourself that the track count and punch-in/out limitations won't get in your way at your chosen bit depth and sample rate. Having 32 tracks may seem a bit excessive, especially where you have virtual tracks to store alternative takes, but if you run a MIDI system and want to record all your MIDI parts as stereo audio tracks, then the more tracks you have available the better. Of course, you can't record on all 16 of the available record tracks (in 32-track mode) at once unless you have the input expansion card, but few project studio owners actually need to record more than eight tracks in one hit, even when recording a band.

The only operational problem I had was with the faders not always responding to my dry fingers, though I've never had a similar experience with any other moving-fader system, including my Emagic Logic Control. All the major features worked intuitively, I thought the effects were good, and using the automation proved to be no problem at all. If you've ever used a Yamaha digital mixer, you'll be able to find your way around the D32XD with very little trouble.

I still think the fan could have been quieter though, especially as most machines of this type are used in a single-room studio. I also felt that the Submixer input levels could have been given a fader bank rather than being controllable only from the screen, although if these inputs are being used only to mix MIDI instruments, it will probably be a case of set and forget.

The hardware audio workstation market is fairly crowded at the moment, with units from each manufacturer having their own strengths. The Korg D32XD should appeal to anyone who needs straightforward operation with a lot of audio tracks, but who doesn't need to record on them all at once.