© 2008 skratchworx.com
skratchworx may not be reproduced in whole or in part without permission.
Introduction
I'll admit I initially tried to dodge reviewing the Zero 8, simply because I have a policy whereby I don't review equipment that has a number of rotary controls that surpasses my age. This obviously meant Gizmo was much more suited to review this mixer than me (sooo fired again ...Giz). However, fate intervened and due to a slight administrative oversight at Korg's end I unexpectedly received the Zero 8 instead of the Zero 4. My initial trepidation was slightly misplaced, as really it's not amazingly complicated - it just has lots of channels and inputs (and effects and MIDI control and Firewire and a touch screen and.......o.k. maybe it is a little more complicated than your average 2-channel scratch mixer).
The Zero 8 covers quite a wide scope it terms of what it can do, and is presumably aimed at those who broadly have a desktop / laptop integrated quite tightly into their home studio or for their live performances. It has enough connectivity to throw in some live instruments or synths, whilst allowing digital audio back and forth over its Firewire connection.
Given the amount of controls it is a bit of a beast, considering what most dj types (myself included) are used to. The majority of the mixer is taken up with the 8 stereo channel strips, with a zone to the right that is home to all of the other mixer controls. Each channel has an input selector, gain, pan, 3-band eq with sweepable mid (and eq type selector), plus a set of send level controls (two for the external busses and one for the Zero FX internal send buss). There are also SOLO toggles for each channel (with included momentary cut action in the opposite direction) and CUE / crossfader routing switches.
The right hand zone has the very cool looking master VU style meters, along with the usual headphone cueing section and return buss level controls. In typical Korg fashion, everything lights up like a Christmas tree when turning on - with a little dancing light display whilst the O/S loads and the DSP gets going. All the controls are backlit and it all looks rather pretty when in action.
I will refrain from detailing in minutiae every possible pot on the mixer, as there are no strange surprises or confusing elements - everything appears as you would expect in a logical order. However, some features warrant a bit more attention.
Input Selection & EQ
Each of the eight channels has an identical set of controls, with a semi-matrix style set of input choices. In terms of physical inputs, they can broadly be split in to two camps. Every channel has a fixed LINE (1/4" jack socket) input which can operate in either balanced or unbalanced mode, as well as a CD / LINE input on RCA connectors. However, the 3x PHONO (with single GND terminal) plus 2x MIC (with selectable phantom power) and 1x GUITAR inputs can all be chosen on any of the 8 channel strips (simultaneously if desired). This gives you a healthy mix of connectivity and routing flexibility. I think a full matrix of all physical inputs would have been too much on a mixer this size (you'd need a hell of an input selector switch!). Each channel also has the slightly more exciting Firewire input option, where you receive audio from your laptop direct to the channel (or you can use the input selector to make your channel strip solely a MIDI controller, or a mixture of Firewire audio and MIDI).
Moving down the channel strip, the next item of interest is the eq selector rotary. The DSP nature of the Zero 8 allows Korg to throw in their trademark "kitchen sink" approach to feature choice, having a range of eq styles ranging from a rather mundane 'Zero EQ' all the way through to 'Slamming' (passing 'Hyped' en-route). If these three don't fit the bill, fear not - there are also 'Boost' and 'Round-Q' presets available. Obviously Korg wouldn't do something as dull as give any indication of what these mean in terms of frequency placement or width, this is music after all - not some boring technical exercise (!). I'm pretty convinced the next Korg mixer will have built in artificial intelligence whereby a projected hologram friend jumps out and shouts encouragement every time you pull off a 'dope move'.
Anyway, as well as the five traditional eq settings there are three isolator types too. These are the more DJ friendly full kill style eq, whereby you can remove all audio. I found it a bit harder to hear differences between the isolator types, and overall I'm not sure how I would pick out a favourite eq or isolator - though I am glad there is at least that choice, silly names aside. Given that this mixer is likely to be used for production and djing it is helpful to have two broad types. All benefit from a sweepable mid-range frequency control, which can be equally fun and useful. The final trick up the eq sleeve is that the final three choices actually turn the eq section into filters. The low eq becomes a high-pass filter whereby 'cutting' the low control moves the cut-off frequency up (i.e. cuts the bass). The high eq works in a similar fashion with a low-pass filter. It fits the whole cut-off range into a half-twist of both controls, so they are very sensitive to movement. The different types seem to add more resonance progressively (labelled 'dense' and 'spiky'). They are very easy to use and great for dj mixing / effects. With a bit of restraint the sensitivity isn't a problem - just be careful!
The only troublesome thing worth noting about the eq / filter selection rotary is that there are audible clicks and audio bursts when moving between the choices in certain circumstances, so you really need to take your pick before you bring your channel live.
Faders
What skratchworx review would be complete without some mention of faders? The inevitable "Can I fit a PXF in it?" is likely to come from somewhere. Frankly, it would be a moot point. Even if you could fit a high end fader in the Zero 8 (which seems like it would be a real headache given the layout and positioning) the crossfader response suffers from noticeable decay / response type issues. This clearly isn't a scratch mixer of any description, so I have no real problems there (though the ability to set up any curve you like via software will tempt the scratch happy). The crossfader feels distinctly different to the channel faders, though I wasn't brave enough to start removing the panels to really get at them and confirm makes / models.
All feel o.k.; the channel faders are a bit smoother to the touch. None feel like they would take days of constant abuse, but again that isn't the market (and do you want an extra £500+ on RRP just for some high-end faders?). Every fader has full control over its contour profile via the touch screen or Zero Edit software, and very useful it is too. It's one of those things you are likely to set and forget, but it is nice to have it exactly as you wish. For the record, even the absolute sharpest profiles have a fair few mm of lag space.
Effects
The Zero 8 has two external send / return busses as well as three internal effects mechanisms. Each channel has send level controls for the two external busses (send signals can be taken pre- or post-fader since Firmware revision 1.50), and the return signal is cueable via the headphone monitoring system.
If it moves, Korg will bung a touch-pad in it - the Zero 8 is no exception. The Zero FX section of the Zero 8 has three independent effects processors. One that can be assigned to a channel at a time, one that works as a send buss and finally one that is assigned to the master output. This is a nicely thought out set and enables most styles of effects to be managed in a sensible way. The usual Korg effects permutations and styles are present - anyone familiar with a Kaoss Pad will feel at home here. They can be a huge amount of fun and the anal side of me appreciated the fact that a lot of the effects have position readouts on the touch screen too (so you know what real number your current touchpad position converts to). Although the channel and send options allow decent integration of different styles of effects, I still kept wishing there was a wet / dry fader to allow a more graceful movement in and out of the insert effects. You can achieve this to some degree in the send mode but it becomes quite tricky to balance the audio levels via the send and return rotaries. Much like the Kaoss Pads, it can be very easy to induce large volume increases whilst messing with certain types of effects (I'm still not sure being able to draw in eq via a touchpad is a good idea!). It will be fine for studio use, but may require more careful thought and judicious use when djing or playing live.
Above the touchpad there are 8 endless rotary encoders with push button action, which can be used for scrolling through the effects types and making certain selections. There are a whole load of effects which are non-touchpad orientated, so you get full control over every aspect of the effect type rather than just 2 levels via the touchpad.
Considering Korg has quite a foothold in the effects market, I'm constantly surprised at how ropey their BPM detection is. Real-time auto detection is never perfect but the constant skipping around is distracting more than anything.
Firewire
Probably one of the biggest selling points of the Zero 8 is the fact that you have an integrated audio interface within the mixer. This means you can stream audio and MIDI over the Firewire connection directly to and from your laptop without needing another soundcard or controller. At 44.1 kHz and 48 kHz sampling rates you get the full complement of channels and mixer features, but as you increase the sampling rate you will lose channel count and also some mixer functions (remember there is only finite bandwidth over Firewire and only finite DSP in the Zero 8 hardware). For example, in 192 kHz mode you will only have 4 stereo channels each way and lose channel eq, the external return busses and all Zero FX functionality. Also, 192 kHz mode requires a special start-up procedure which cannot be switched to another sampling rate without power cycling the mixer. I suspect most users will only ever use this mode in very limited circumstances. The manual states no go in OS X for 192 kHz, and also a whole host of other OS X issues. Whether these have been resolved in Firmware revision 1.50 is unclear.
Within Windows, the Zero 8 appears as a 16-in / 16-out ASIO sound device - allowing free assignment of the 8 stereo channels in each direction. Whilst using the Zero 8 channels in Firewire mode you can independently select what inputs are sent to your computer (pre-everything) - so you can have your Phono 1 & 2 automatically routed into your favourite vinyl emulation software for timecode vinyl control whilst using the mixer channels for the returned audio output. If you are using the physical inputs on your channels, you can have these sent pre-eq, pre-fader or post-fader. Finally, you can also have any of the external send / return busses, crossfader buss A or B, the Zero FX send / return buss or the master output routed via the Firewire (obviously you can only have 8 items at once!). This is pretty comprehensive, though some users have raised that they would like to be able to return audio straight into the CUE or MASTER buss, so that the Zero 8 could faithfully reproduce an on-screen set-up in software such as Ableton Live. I think this is a valid point, and hopefully only a firmware change away. You can kind of work around this but it involves using up mixer channels. The ironic thing being that the Zero 8 comes with a copy of Ableton Live Lite 6, which only allows a single stereo input and output.....doh. Still, usable to some degree when in MIDI control mode.
What would life be without some kind of computer related headache? Well, the Zero 8 and my laptop didn't really want to play too well together. I suffered routine ASIO streaming errors at all buffer sizes, which cause full audio loss / metallic buzzing sounds and a need to reset the sampling rate in the Zero 8 Firewire control panel before any more audio is passed. I tried troubleshooting this, but never really got anywhere nearer a resolution given the relative infrequent nature of the problems. My laptop has a Texas Instruments chipset throughout, which is usually the first port of call for reliable Firewire behaviour. Without going into the gory details, the XP SP2 install I use has the usual audio tweaks - and no manner of disabling all non-essential hardware features fixed the streaming errors. I have no other Firewire interfaces or PCs to check on, so I will have to sit on the fence with this one. As seems to be the case with audio over Firewire, your mileage may vary. Obviously I'd love to simply blame Korg's drivers, but I have no real evidence for this. It is a shame, as it was a total show stopper for me. Also, if your laptop needs a reboot you will get a loud audio spike through the Zero 8 (though hot-swapping is meant to be a feature of Firewire, it is not recommended).
MIDI
After all this audio excitement, it is almost easy to forget that the Zero 8 has comprehensive MIDI capabilities too. Virtually every control can be used to send MIDI, including the touchpad. There is also a controller set of 8 endless encoders with push button functionality which can be switched between 4 different banks. The channels can be operated in full MIDI mode (selected at the input switch) which routes the LINE audio input straight to the master buss and makes all of the controls send MIDI messages instead of controlling audio. It also changes the backlight colour from orange to a cool blue.
There is a mixed mode, whereby the main channel audio controls function but you get the pan and send levels as MIDI instead. Through the Zero Edit software you can change what controller message each item sends if required, and the unit can also send and receive MIDI clock. This seemed to work fine sending clock from Ableton Live to the Zero 8, which then synced up the Zero 8 effects perfectly - though there is no visual confirmation on the Zero 8 that it has received the clock, which is a tad unnerving. Ableton received clock o.k. from the Zero 8, but I found realistically it was easier to align Ableton manually. Maybe a bit more practice needed! There are traditional hardware MIDI IN / OUT ports on the Zero 8 too, if you need to sync or send messages to other hardware.
Quality?
There have been some internet murmurings (the best type of murmur) and concerns about a couple of aspects of the Zero 8. These have been centred around perceived 'hiss' at the Zero 8 outputs, and the non-movement of the VU style master meters unless the mixer is run very 'hot'. I think Korg could have headed off some of these concerns by having a manual that wasn't as unbelievably threadbare and weak. The whole thing reads like a quick-start guide, and is lacking in any technical depth or help whatsoever. I know detailed manuals aren't cool, but I am sure it would reduce the support burden created by inadequate explanation of the mixer functions. Time well spent, perhaps? In any case I will try to give my opinion on these matters (skip to next section if appropriate!).
Firstly, the easy one - the VU master meters. Part of the confusion lies in that the majority of people are used to operating analog mixers with defined nominal working levels and standard headroom, and perhaps not too many problems in-between. The Korg Zero 8 is fully DSP based, meaning you need to think slightly differently about how you work. The absolute stopping point of digital audio is 0dBFS, so to relate to an analog way of working, you need to have an equivalent nominal operating level which gives you 20dB or so of headroom. The dynamic range of a modern 24-bit system means that you can still be a very comfortable distance away from the noise floor when peaking at -20dBFS. Korg have chosen to have the master VU meters relate exactly to the dBFS scale, so that they show you when you are going to start getting distortion problems from digital clipping. This is useful in a practical sense, but means that unless you have all 8 channels passing audio at normal levels and your master output at near full then you won't see the VU meters even tickle slightly. This is sensible digital gain structure, but doesn't placate end users who want to see sexy needles dancing about. I suspect Korg will most likely re-calibrate the meters to show 0VU as something significantly less than 0dBFS, which will keep everyone happy and in a roundabout way make people work at more sensible dBFS levels.
Secondly, the 'hiss'. This is a extremely low level noise that is constantly at the outputs irrespective of any input selection or control status. It sounds bad on paper, but is only there if you go looking for it. Importantly it doesn't increase with increased gain and is totally swamped by the noise of the pre-amps if you are using them. Therefore, to me, it is kind of irrelevant. Korg may have to introduce some kind of noise gate / squelch to suppress it, or it may be a genuine hardware issue that needs fixing. They are apparently working on a fix, which will be released in April - though the impression was given that it may require a trip to the service centre to implement. If I owned the mixer, I wouldn't bother sending it off for this.
To my ears, the mixer sounds good. I don't feel there are any noise problems during normal operation, and everything sounds clear and well balanced. The headphone output is perhaps a bit underpowered, and I could see someone struggling in a noisy environment. People also reasonably expect good sound quality at this price point, and I think the Zero 8 delivers this. In terms of build quality, the faders feel pretty standard and the pots have an element of wobble - but the Zero 8 is more akin to a console than a hard wearing 2-channel dj mixer.
Final Thoughts
Someone considering a Zero 8 is most likely to be fairly clear on what they need, because although it is flexible - it is a step change away from a normal dj mixer. You don't drop this kind of cash on a whim. I've had a huge amount of fun with it, and I don't really routinely use software in a live performance sense. There is something very satisfying about having loads of audio inputs, effects and neat control all from a central point - especially if you want to record all your channels discreetly during a live performance.
In some senses it is typical Korg, but a bit more technical rigour in the manual would be nice. Software like Ableton Live is so open ended that there will never be one controller or way of working that suits everyone, but the Zero 8 has quite a few of the standard bases covered.
Ratings
Build Quality - 8/10
Generally good with slightly rough feeling crossfader and plastic wobbly pots.
Sound Quality - 8.5/10
Sounds good to me.
Features & Implementation - 9.5/10
A direct Firewire link to the master and cue buss would be nice. Definitely not short of features!
Value For Money - 9.5/10
You get 8 channels, an effects unit and a 16-in / 16-out Firewire interface all in one. Can't be bad.
The Bottom Line
There isn't a whole lot on the market to compare to the Zero 8. Aside from a few minor grumbles I think Korg has done a great job (assuming you don't have Firewire problems like me......)