There's a bewildering choice of audio interfaces on the market, but as the requirement for more I/O channels increases, so the choice decreases. More channels means more bandwidth requirement, so most interfaces of this kind use either Firewire or some form of direct PCI connection to hook up to the host computer. The TC Electronic Studio Konnekt 48 is of the former type and offers 12 channels of analogue I/O, internal DSP effects and speaker management, and even comes with a handy remote control unit.
Compatible with both Mac and PC machines, the Konnekt 48 will work with Mac OS 10.4 or higher and Windows XP or Vista X32, and comes with its own NEAR control panel software. After you install the control panel and driver software the Konnekt 48 is ready for use, though with the version I used I had to restart after letting the software update the unit's firmware. When I first tried the unit some months ago the software was a little buggy, which is why I've held off on the review until now. I'm glad to say that the public Beta software I used for this review worked fine with my Mac, and audio playback was uninterrupted by unwelcome clicks or pops — even at buffer sizes of 128 samples or below. By the time you read this, the release version of the driver will be on the TC web site.
The Studio Konnekt 48 I/O section comprises 12 analogue channels — eight line inputs (switchable for -10dBv or +4dBu operation) on the rear panel, and four inputs for the TC Impact II series mic/line preamps, offering gain trim, switchable phantom power (global) and 20dB pad buttons, on the front panel. The four Neutrik combi XLR/jack (mic/line) inputs on the front of the Studio Konnekt 48 also offer high-Z guitar settings that use additional buffer circuitry to avoid loading the guitar pickups. A clever touch is that the input stage automatically senses when a high-impedance source is connected, at which point a relay switches in the high-Z circuitry.
There are eight analogue outputs on balanced TRS sockets and two further main outputs (1/2), featuring digitally controlled analogue level control, on XLRs. In addition to this, two sets of ADAT/TOS ports add eight further channels of ADAT I/O (two sets are needed for 88.2kHz or 96kHz operation in SMux mode). Then there's the S/PDIF stereo digital I/O — so there's no shortage of physical connectivity.
You should be aware that at 'normal' sample rates you can't use both ADAT ports at once to double the channel count, although you can configure one as a stereo Toslink port and use that in addition to eight ADAT channels at 44.1kHz or 48kHz. If you don't need ADAT interfacing, both optical ports can be configured as stereo Toslink ports, so nothing is redundant. As part of my testing during the review, I plugged in a Behringer ADA8000 eight-channel mic preamp, which interfaces via ADAT, and set it to slave from the Studio Konnekt 48. This worked with no fuss, giving me eight more ins and outs.
A pair of standard MIDI I/O ports are provided on the rear panel, and in terms of computer connectivity the Konnekt 48 sports two Firewire ports, so a further Firewire device may be daisy-chained if bandwidth makes this a practical option. Word clock connections are available on the usual BNCs to faciliate synchronisation. If the external clock signal drops out for any reason (and this includes any digital input being used as a sync source) an Advanced Clock Recovery system steps in and generates a free-wheeling clock signal at the correct sample rate to keep the system running until a valid clock source is picked up again. Also onboard is TC's 'JET' Jitter Elimination Technology. to clean up the incoming sync clock when other devices are used as the clock master.
An LED-ladder meter section on the front panel monitors the 12 analogue channels as stereo pairs, as well as indicating activity in the ADAT ports, the Toslink ports and the S/PDIF ports. A further LED confirms that the Firewire link is working.
You also get two independent headphone ports that can have different sources and levels, set within the NEAR mixer software control panel. It's even possible to route two independent signals to the left and right sides of your headphones, so if the singer likes to work with one phone off you can silence that side, to avoid spill. Alternatively, you could have the track in one ear and a click in the other. If this all seems impressive for a 1U I/O box, the Konnekt 48 has further surprises in store for you.
TC Electronic have a history of building DSP-powered effects, both as hardware units and as plug-ins fuelled by their Powercore platform, so they've taken the logical step of adding some DSP-driven features hosted by the two on-board DSP chips. These provide on-board mixing, and monitor/headphone submixing and speaker management for multi-channel work. On top of that you get the really high-quality Fabrik R Studio digital reverb, based on TC's System 4000 hardware algorithms, and TC's Fabrik C Studio mastering channel strip. This offers four-band EQ plus multi-band compression and limiting derived from the algorithms used in their flagship System 6000 platform, so you're getting the real deal here. What's more, you can run up to four of them. Additionally, TC have included their ResFilter plug-in, the Assimilator 'fingerprint EQ' and a utility plug-in that allows external hardware devices to be connected and routed within the mixer in the same way as conventional plug-ins.
As a mixer, the Studio Konnekt 48 offers a 24:8 format, and is capable of routing 30 streams of audio to the connected DAW (24 inputs plus sends and outputs from the DSP effects) and receiving 28 streams from the DAW at the same time. It uses 48-bit, double-precision summing, with 56-bit processing for the mix engine, so it may well be possible to gain better audio quality by mixing channels and groups from your DAW in the Studio Konnekt 48 and then routing the stereo mix back to your computer, rather than mixing everything in the DAW itself — depending on which DAW you use, of course. (If you prefer to mix 'inside the box', the Studio Konnekt 48 control panel still makes it easy to arrange zero-latency monitoring with effects for tracking.) The mixer includes extremely flexible routing options; a really neat touch is that the hardware senses which connections are being used, so when you open the mixer control panel you can opt to view only channels that are actually connected.
The use of DSP enables the Studio Konnekt 48 to function as a controller for surround speaker systems (even offering an adjustable crossover frequency for the subwoofer), which in itself can save a fortune in surround monitor controllers. The speaker management section employs technology from Dynaudio's AIR series DSP-controlled monitor speakers, and in addition to controlling overall level it can handle individual speaker level and delay settings, and bass management for any sub you have connected. It also has the ability to store and recall three separate speaker setups, which can include headphones, if you wish. In theory, then, you could even define a speaker setup comprising only headphones and a subwoofer, though my guess is that few people will find a need to do this! As mentioned earlier, the two main outputs use digitally controlled analogue gain control, so there's no loss of resolution when you turn your monitors down.
Chip Off The Old Block
The Konnekt 48 is the latest addition to TC's line of Konnekt Firewire audio interfaces based around the versatile Dice II chip. This chip is a spin-off from TC Electronic technology (TC Applied Technology) and is also available to the manufacturers of competing products (I know Alesis, Presonus and SSL already use it). Although not all of the chip's power is used here, the Konnekt 48 includes substantial DSP capability (apparently half the power of a Powercore Firewire unit derived from two DSP chips), allowing it to be used as a mix engine and effects processor for setting up zero-latency monitor mixes with effects, or for other mixing and routing purposes.
Multiple Konnekt devices can be used togther: you can use up to two Konnekt 48s at the same time, two Konnekt Lives together with a Konnekt 48, a Digital Konnekt plus a Konnekt 24D and a Konnekt 48 or four Konnekt 8s. All communicate with the same NEAR software control panel for setting up mixes or monitoring. Sample rates of up to 192kHz are supported, except at the ADAT ports, which have a maximum capability of 96kHz in SMux mode.
I tend to like a simple life, so I'm generally a bit sceptical of any interface that comes with its own software mixer or effects. They all claim they do it to allow near zero-latency monitoring, but using buffer sizes of 128 and below I've never really found latency to be a problem, and having more elements in the signal path can be confusing. However, the NEAR mixer is pretty straightforward and allows you to combine any of the live inputs with the DAW outputs, while adding effects if required, so if you want to set up a monitor mix where the singer has just the right amount of reverb in the cans, it is easily done. If you don't want to use the mixer functions at all, however, you don't have to. Simply mute or turn down all the channels except for the DAW output, solo the DAW output, or un-tick the Direct Monitor tick-box at the bottom left on the Mixer page, and you can treat the Studio Konnekt 48 as a rather nice 'dumb' interface with half a Powercore's-worth of effects plug-ins and a remote volume control. NEAR operated perfectly during my tests, although its controls tend to lag a little way behind your mouse movements — something that I'm told TC are trying to improve. The remote control is a great asset, though (see next section), as often-used functions, such as monitor level and talkback, are right where you need them, and you can also control a surround mix if you happen to be working in surround. The software even includes a guitar tuner, which can also be activated from the remote control.
Audio interfaces are often tucked away in racks where you can't reach them easily. The Studio Konnekt 48 solves this problem with a neat little remote control box that hooks up to the main unit using a standard Cat 5 cable. This looks after all the main speaker and monitoring functions, including monitor level control, mix levels, reverb level/decay time, speaker selection, aux sends, and talkback via a built-in mic. The Talkback channel may be routed to Main, Aux 1 and/or Aux 2, or to none of them. By default, the talkback is also routed to the main speakers, which caught me out at first, but if you click 'Main' in the NEAR mixer panel, the light will go out. A Panel button on the remote opens and closes the NEAR Mixer panel, which is much better than having to do it by mouse every time.
To economise on the number of analogue-to-digital converters, the internal talkback mic uses input channel 12 by default, but this can be disabled by clicking the 'X' in the talkback strip, which causes channel 12 to become available for use as a conventional line input. When the talkback mic is using channel 12 its output is also sent over the Firewire bus, regardless of whether the Talkback button is pressed or not, so that it is available to your computer as a general note-taking mic, or even for use when making telephone calls via Skype! Furthermore, when two or more Konnekt devices are working together in a system it should be possible to allow one device to listen in on the microphone signal sent by another.
Should you wish to use your own external mic to handle talkback, rather than the one built into the remote, you can use mic input 4, or channel 12 if you're feeding from a separate mic preamp with a line-level output. Both have full talkback mic routing. When the Talkback mic button is pressed briefly on the remote, the microphone latches on, but if you press and hold the button, the mic is active only for as long as you keep the button held down. Personally, I'd like some way to deactivate the latching mode, to avoid accidents such as leaving the mic 'live' while discussing the drummer's personal hygiene!
Although the volume control on the remote box looks rather like a trackball, it is, in fact, a rotary encoder with a built-in push-switch and a 'ring of LEDs' position indicator. Generally you just hit the button corresponding to the function you wish to adjust, then turn the knob. After a few seconds of not being used (the actual time is user selectable), the knob function then reverts back to master volume control.
The Studio Konnekt 48's included plug-ins are definitely worthy of comment, because they really do sound a whole lot better than the type of 'me too' plug-ins that you might have been expecting. The Fabrik Reverb, for example, uses a simple graphical interface for parameter adjustment — you drag coloured balls around a triangular space — but its sound has the same dense and sumptuous quality as TC's hardware algorithmic reverb units, and it doesn't hog your computer's entire CPU. Similarly, the channel EQ and multi-band dynamics processors are first-class, and Assimilator (a 'fingerprint' or matching EQ) is a very handy tool for trying to give one piece of audio, whether it's a single track or a complete mix, the same spectral balance as a reference track.
Initially, I thought it would have been neat if TC had also allowed you to use the plug-ins directly within your own DAW, as Powercore can — then I discovered that they have! You simply need to choose the 'Plug-in' routing mode rather than the 'Internal' one, in the relevant plug-in setup window within the NEAR software, after which the effects work just like Powercore (AU or VST) plug-ins and appear in your DAW's plug-in list. As with Powercore, latency is doubled when you use the DSP-assisted plug-ins within your DAW, so if this is a problem you can just use them for mixing. Alternatively, if you only need the reverb you can switch off plug-in delay compensation for the buses and set up the reverb as a send effect.
The last six outputs listed in the DAW's I/O menu address the four possible Fabrik C mastering plug-in sends and two possible Fabrik R reverb sends (the DSP can support a maximum of four Fabrik Cs and two Fabrik Rs running at the same time), so you can route channels or buses to the plug-ins. Similarly, the outputs from the plug-ins are listed as sources that are accessible from within your DAW. Mac users running Leopard and Logic will see the correct descriptive source and destination names for all the inputs and outputs in Logic's I/O list, but under Tiger, which I was running on my G5 at the time of the test, the list shows only numbers, though I was able to type in the correct descriptions within Logic's I/O labels window.
When you consider that the Konnekt 48 can save you the cost of a separate monitor controller, and factor in the quality of the onboard DSP effects, its price is very reasonable. The mic preamps sound very clean and transparent — they certainly compare well with anything available on a similarly priced competing interface — and having four of them is very welcome.
During my tests I couldn't fault the Konnekt 48's performance, and although it has a couple of little design quirks, such as the sharing of a converter between talkback and line input 12, it doesn't take that much effort to get your head around how it works. Its audio quality is good for a piece of gear with this sort of price tag, and the flexibility of the NEAR mixer should meet most needs.
On a practical note, more comprehensive level metering would have been appreciated, but panel space is always a limitation with 1U boxes where half the space is taken up with mic inputs. You can see all the level info you need on your DAW's meters, of course, but where space isn't an issue there's something rather nice about working with an interface that has a physical bar-graph meter for each input.
The Konnekt 48 isn't the only multi-channel audio interface on the market at this price point, and it may not be the most obvious choice if you don't need its mixer and effects capability, but I think anyone who tried it would be impressed by how seamlessly it can fit into a system and how useful those extra functions can be in real-life studio work.
Some obvious alternatives, if you're in the market purely for an audio interface, are the recently announced Mark Of The Unicorn 828 Mk3 (look out for an SOS review in a forthcoming issue, and also see page 194 of this issue), the Alesis I/O26 (reviewed SOS June 2007), the Presonus Firestudio (reviewed December 2007) and the RME Fireface 400 (reviewed July 2007). Competing interfaces also often include software-controlled mixer facilities and occasionally DSP effects, but where the Konnekt 48 stands out from the competition is in the very high quality of its DSP effects.