The Komplete Audio 6 (which we'll henceforth call the KA6) is a computer audio interface
from Native Instruments for Mac or Windows. It's a robust unit with a stylish design,
low latency and many useful features.
You can simply use the built-in audio interface of your computer, but there are many advantages
of using an external unit. For example, they typically allow XLR microphone connection,
they provide other inputs including MIDI connections and they can offer decreased latency (that's
delay due to digital/analogue signal conversion). Audio interfaces can also offer hardware monitoring
as you record, and they can offer multiple outputs.
The KA6 converts analogue signals (that's vibrations in the air, or ordinary sounds)
into digital representations on your computer, using 24-bit resolution. This is better than
CD quality and means that the unit records changes in amplitude of the incoming sound
from a microphone or instrument using more than 16 million different levels. The interface
can also record using sample rates of either 44.1, 48, 88.2 or 96 KHz. What this means
is it can record that signal amplitude up to 96,000 times per second. The KA6 will always
record using 24-bit, but make sure this is taken advantage of in the preferences of your
digital audio workstation, or DAW. As for the sample rate, the KA6 will record using
44.1KHz by default, and this is perfectly sufficient for most purposes, but if you wish
to record using a higher sample rate, you set this in software. You can set a default
at the driver interface in Windows or Mac, and you can also choose within a given audio
project's settings.
The other important setting in software for this or any other audio interface is the I/O
buffer size. This is something you set in the preferences of your DAW. When performing
digital to analogue or analogue to digital conversion, the audio driver needs to store
small amounts of data which are then sent to the CPU for processing. A larger buffer
makes it easier for your computer to process this information but does introduce a greater
delay. The art here then is to choose the lowest value you can that does not cause your
music software to stall with buffer warning messages or pops or clicks. Try around midway
to start with, on a modern computer. We can see here that this means the system will take
only 7.9 milliseconds to convert a digital signal into analogue (that is zeroes and ones
into sound we can hear) while it will take 17 milliseconds to convert incoming audio
from analogue into digital then back again out of the computer from digital into analogue
- that is a roundtrip conversion. This is very fast indeed, but human hearing can detect
delays of greater than around 10 milliseconds and we'll discuss this more later on.
Now lets examine the Komplete Audio 6 hardware and understand how to use it.
Beginning with the front panel, you can see two inputs on the left here. These - inputs
1 and 2 - are not the only inputs on this unit but they are the primary and by far the
most versatile ones. They are both mono inputs and they're combination sockets: they can
accept either XLR microphone plugs or 1/4 inch TS or phone plugs such as might come
from a guitar. You press the tab here to release XLR plugs and the 1/4 inch sockets are what
is known as "balanced", to help eliminate any interference.
The gain dial beside each input determines how much signal is allow into the unit. It
can be good to keep this at about 75%.
This button here only affects 1/4 inch jack inputs, not XLR connections. Instruments such
as guitars provide a weak audio signal and when this button is pressed down the KA6 will
amplify the signal a little to bring it up to what is known as line level. This is the
optimum signal level for audio within the system and instruments such as synthesisers
will already output at this level, so leave the button up for connections such as these.
We mentioned inputs 1 and 2 are mono, so of course in order to have a stereo input, you
connect a cable into each - the left hand channel to the left and the right hand channel
to the right.
This section here is for hardware monitoring. In normal circumstances a signal received
into the KA6 will be routed through USB to your computer once this unit is selected as
the audio interface. You will be able to select, for example, inputs 1 and 2, and even monitor
the incoming signal on a track in an application like Logic Pro. There you can even add software
effects and listen to the processed signal.
The key point here, though, is "processed signal". This software monitoring is all well
and good, but it takes some time for the interface to convert the incoming analogue audio into
a digital form, then back again into an analogue form for us to hear. While anything less than
10 milliseconds tends to be imperceptible, this delay, or "latency" can be as long as
30 milliseconds. This can introduce a distraction, especially if a singer can hear themselves
both as they sing, and a moment later via software monitoring through speakers or headphones.
Hardware, or direct, monitoring routes an audio input directly to an output, bypassing
the USB connection, so that the sound can be heard though speakers or headphones instantly
- it stays in the analogue domain. When you see singers with headphones on, they might
be listening to the music, but are likely hearing their own voice via hardware monitoring
- it's routed straight to the outputs, or possibly via other analogue hardware effects
which do not introduce digital delay.
To enable hardware monitoring on the KA6, you need to turn it on, here. This routes
the signal received by inputs 1 and 2 directly through to outputs 1 and 2 on the back of
the unit (which we'll discuss later). Note this incoming signal is still made available
to the computer via USB, but is additionally routed straight through to the output. If
you hold the Monitoring On button down it will cycle between routing the input signal
to outputs 3 and 4 instead, or routing the incoming signal to outputs 1 & 2 and 3 & 4.
We'll come to discussing these outputs later, but in this manner it's possible to listen
to hardware monitored input through headphones and/or one set of speakers, while listening
to audio from the computer though another.
Also in the Monitoring section, the volume knob determines the output level of the monitored
signal. You can send the input signal through unaffected or you can lower it, allowing for
a different mix level with whatever else might be being sent to the outputs by the computer
via USB.
Let's say you have only a microphone plugged into the KA6, using input 1, which is the
left hand channel. If you monitor this, you'll only hear it in your left speaker or headphone
- it's mono. When this button is pressed down the KA6 will output that signal into both
channels, left and right, which tends to sound preferable. That's the purpose of it. But
beware, because if you're using a stereo input (that is putting plugs into both inputs 1
and 2) and you have this button pressed down, both channels will be combined in the monitoring
and you'll lose that stereo effect.
These controls here are all to do with the headphones output of the KA6. The socket expects
a 1/4 inch stereo TRS plug. The volume knob setting the output level is completely independent
of the main volume knob on the top of the unit which we'll discuss in a moment. In other
words, you can be listening to the outputs loudly through headphones while quietly through
speakers. The maximum volume through the headphone jack however is not especially loud, and depending
on the impedance of your headphones you may even wish to boost the signal further via
a headphone amp.
Certain software such as DAWs will allow you to direct audio to any output of your interface.
You might select outputs 3 and 4 of the KA6 instead of the primary outputs 1 and 2. In
another scenario you might be routing monitored inputs through to outputs 3 and 4 while computer
sound goes to outputs 1 and 2. In this case you might use this button here to listen to
the monitored audio only in your headphones. It decides which outputs the headphones will
hear - outputs 1 and 2 or 3 and 4. If not recording, in most cases you'll leave this
button up so you hear the main outputs, and you might turn down the output to the speakers,
which we'll discuss in a moment.
Now let's move round to the back of the KA6 and see what's provided there.
Starting on the far left, condenser microphones, which are extremely sensitive and have excellent
frequency response, require a small amount of electrical power. In order to provide this
to your microphone, connected through one of the XLR sockets on the front of the unit,
press this button in.
Below the 48v button is the main USB output for you to connect the interface to your computer.
This is a USB 2.0 connection. On the right of this we have two MIDI sockets.
If you are using a controller keyboard which doesn't connect to your computer via USB,
you might
connect it via MIDI to here instead and select this MIDI input in your DAW. Alternatively,
you might send MIDI information from your sequencer to an external synthesizer connected
via the MIDI out port here. In that way you can tell the hardware synth what notes to
play and send other messages.
The main outputs of the KA6 are these, outputs 1 and 2, which are mono 1/4 inch TS jacks,
one for each channel. These are mostly likely going to be connected directly to active (that
means powered) speakers or to a mixer or amplifier unit. These are the primary audio outputs
for the KA6 and remember one of our options was to monitor inputs straight to here.
Should you wish to also output audio from the KA6 to another destination, two more balanced
outputs are provided - 3 and 4 - here. You might find these useful if working with surround
sound, but bear in mind the volume will be loud, as there is no moderating control for
these on the unit.
Earlier on we discussed the fact you can connect either microphones, guitars or line level
instruments such as synthesisers to the front inputs, 1 and 2 on the KA6 and there you can
choose to boost the signal and you can also set the gain.
On the back on the unit here
we are provided with two further inputs. These are not XLR but only 1/4 inch TS inputs and
this time they're fixed at line level - so they're ideal for the connection of hardware
synths, leaving the other inputs free perhaps for microphones at the front.
With the driver installed, these inputs will show up as "3 and 4" in DAW software, so you can record
from them. But notice these inputs do not support hardware, or direct, monitoring. If
you want to hear the inputs you need to do so in software
Finally on the back of the KA6, S/PDIF connections are also provided. This stands for Sony/Philips
Digital Interface Format. These can carry a digital, as opposed to analogue, audio signal,
to and from supporting devices. They're not very widely used but if you have a device
that's compatible - perhaps a DAT player or certain synthesisers - then you can connect
using them and avoid unnecessary digital to analogue, or analogue to digital conversion.
Now let's review the top of the Komplete Audio 6. This consists of indicator lights and one
central dial. On the left hand side here, specific inputs light green when a signal
is detected and they light red when that signal is too loud, or "clipping". Turn up gain,
or output on the external device, until the lights just fail to turn red.
When there is an outgoing signal to either outputs 1 and 2 or 3 and 4, this is indicated
with a green light. But note this does not include a signal which has been directed to
those outputs for the purpose of monitoring. These lights come on when a signal is received
from your computer directed to an output via USB (it doesn't matter whether any cables
are actually plugged into the sockets).
The S/PDIF Sync light just here becomes orange when an external digital clock is established.
You choose whether external or internal synchronisation should be used for connections in the software
driver settings.
The MIDI lights here indicate whether MIDI messages are being sent or received, the 48V
light here indicates whether that power is being supplied, not whether it is necessarily
being consumed, and the USB light here indicates the status of the connection with your computer.
If it's solid, a connection is properly established, if it's flashing there's been a problem and
you could try unplugging the cable and plugging it in again.
Coming down to these lights on the bottom right, we discussed how when you wish to use
hardware monitoring, you can choose to route the input signal to either outputs 1 and 2
or 3 and 4 or to both sets of outputs at the same time. These lights indicate accordingly
the current active routing. Similarly we know there's a button on the front for deciding
which audio outputs you would like routed to the headphones socket. If you're listening
to music output by your computer you'll likely have this set to 1 and 2, but if you're monitoring
yourself singing while music plays through the main outputs, you might be listening to
the input routed to outputs 3 and 4 here.
We can't leave the KA6 without mentioning this large dial on the top. As it says here,
this controls the volume of primary outputs 1 and 2 on the back of the unit. Most of the
time your computer's applications will be selecting these outputs via USB so you use
this to control the volume of music etc. Remember you will already have separately controlled
the volume of any signal you might be monitoring to these outputs. That signal then becomes
a constituent part of this overall output, though you can also be listening to and setting
the volume of the overall output separately when listening through headphones.
That's a guide to how to use the Komplete Audio 6. In most cases you will likely have
it set in software to use 24-bit, 44.1 KHz conversion and you will have powered or active
(that means internally amplified) speakers connected to outputs 1 and 2 on the back of
the unit. You'll use the left hand XLR socket on the front of the KA6 to record from a condenser
microphone, making sure that phantom power is turned on. You might optionally monitor
this input to outputs 1 and 2 or 3 and 4, also listening through headphones. This audio
will be provided via USB to your computer. Meanwhile, you might have a synthesizer connected
to inputs 3 and 4 on the back of the KA6, making its sound available for recording via
those inputs in your sequencer. Using the MIDI Out socket on the back of the KA6 you
could send control messages from your computer to that connected synth, telling it what notes
to play. This would be a typical home studio setup.
We hope you've found this guide helpful. Happy recording!