choosing a
mixer
for your home or
project studio
Which Mixer? Everything you
need to know
by Tweak
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This
is the Mixer Class!!
Critical points we will cover:
1.
The difference between the mixer approach and the "mixerless"
approach
2.
Critcal mixer features--sends-returns, inserts, sub
outs, direct outs
3.
The types of analog mixers and which is most appropriate
for different recording situations
4.
The difference between analog and digital mixers, who
needs which, why
5. A
rudimentary understanding of the new breed of firewire/
USB mixers and how they can be used as audio interfaces |
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On the next four pages we
will cover a lot of mixers and approaches to building your studio. My goal is
when you are done reading this article, you will have a really good
understanding of mixers, enough to make an intelligent decision on what you
need. If not, this article links to live discussion going on at
studio-central on the topic of mixers.
Understanding mixers is
important. When you can talk mixers, you talk the studio talk. Why?
Everything connects to them! This is true even if you go mixerless, because if
you do then you have to understand software mixers, which have similar
functionality and use the same terminology.

Mackie Onyx 1640 16-Channel Mixer
What does a Mixer actually do?
A mixer or mixing console or mixing board all refer to the same
thing: a device that allows you to balance, position, effect and
equalize its different audio channels into a good sounding sonic image
that we call a mix. You can add effects to some channels but not others,
position instruments to a location in the stereo field, route channels
to outboard gear that produces an interesting effect and "sculpt" the
sound of each channel with a dedicated equalizer where you can vary the
bass, treble and mid range in such a way that the whole song "gels" into
a work of beauty. You can dramatically improve your music made of
multiple tracks by learning how to mix.
Those starting a
studio need to decide early on what is going to be the center of
the studio. As you saw in the class on Audio Basics, there are 4
approaches here. The first, and most traditional, is the analog
mixing board, where all the outputs of everything is matrixed with
all the inputs and the output feed another recorder (which is typically
a computer soundcard and DAW. Second, you may decide to go "mixerless"
using an audio interface and make the computer sequencer
your center, where all the sound goes for mixing on audio tracks and
plugins. Certainly, that approach requires the least amount of cash and
gear. It's an easy way to get started. The third path, used mainly by
those using multi-track recorders, is where a digital mixer
is used. Fourth and finally, there is the newest breed of
mixer/audio interface combinations. These sometimes add a a
control surface and even a MIDI interface, making it an all-in-one
solution. We will talk about all these approaches in detail.
Making this choice
is one of the most difficult for the home and project studio, as no
piece of gear has as many ramifications for the future path of your
studio. The larger your enterprise, the tougher the call as you only
want to go through this once. How many channels do you need?
Conventional wisdom answers: one more than you currently have. :) OK,
stop rolling on the floor already. With mixers, you should build in a
little room to grow. Maybe more than a little. You will buy more gear
again after you recover from this major purchase. The hardest thing
about the decisions you have to look ahead 3-5 years and formulate a
concept of what you want your studio to become.
Going Mixerless
Is a mixer even
necessary for your rig? Maybe not--given that you are doing your mixes in
the digital domain of your computer with a professional sequencer like
Logic or Sonar, Cubase, Nuendo or Digital Performer or Pro Tools LE. If you have
a multi input audio interface, it is easy to simply connect your
sources to the interface and your outputs to a monitoring system. The audio
interface does all the functions of a soundcard, but adds more inputs and
outputs.
Even many
professionals are mixerless now. With a control surface like
Mackie Control you can have a hardware mixer-like surface to control all the
leveling and effecting you do in the software's mixer. Just get good
preamps for your mics if your audio interface doesn't have them. Your
mix is actually created in the CPU of your computer. Streams of digital
audio, (which are essentially numbers) are mathematically added together and
scaled to create your stereo or surround output.
Who
should go Mixerless?
- A)
People with only a few pieces of hardware
- B)
People who want to keep their signal totally in the
digital domain
-
C) People with FAST computers who will
be using a lot of virtual instruments or have a lot of audio
interface channels and premium preamps.
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Another option related
to the mixerless approach are the control surface/audio interface
combos, such as the Tascam FW1884 and the Digidesign 002.
These are more than just a control surface and more than just a mixer.
These hybrid devices combine a basic digital audio mixer, control
surface, audio interface and MIDI interface all in one. Because they
function as an audio interface, they replace the soundcard in your rig. So
if you are getting one of these you don't need another mixer, at least not
until you run out of inputs. The same limitations apply as with the
mixerless approach. There may be limited inputs and outputs (typically 8 in
8 out) which is fine for small rigs and small bands, but not for a full band
where you mic the drummer and want everyone playing together. We'll talk
about these devices on the
control surfaces page.
Can you go Mixerless
with a stereo soundcard?
Sure you can. You would
need a dual (2 channel) mic preamp to connect to the soundcard. You would
be limited to laying down 2 mono tracks at a time. With 2 channels you
could record stereo tracks or you can actually jam with a buddy. Why
doesn't everyone do this? Well you lose out when you start adding hardware
synths. You will have to record everything as audio, and that takes up lots
of storage and the CPU gets burdened pretty quick.
But you can go this route
if you are just using 1-2 mics and plan to only use soft synths and
samplers, or programs like Fruity Loops, Acid, Reason, etc for your
instruments. Limit yourself there and you will never need a mixer. The
disadvantages here can be profound, however. You are passing all your audio
through the soundcard's converters. If its a good soundcard, that is not a
big issue. If its not a good soundcard, your quality will suffer. However,
the amount of money you save is miniscule these days as small audio
interfaces are really inexpensive.
Where the mixer
fits in: The Front End and Back End
You can add a mixer
as the front end of your audio interface as well as you can to a
soundcard. As a "front end" the mixer routes a variety of signals, like
mics, synths, guitars to the soundcard or audio interface that you want to
record. As a "back end" to the audio interface, it receives the signals
from it, and allows you to mix the various analog outputs of the interface
on faders. Not all mixers can function as both a front and back end to your
computer. We will get into which can do both and which cannot.
Of course you can go
mixerless with just an audio interface. If that is what you want to do,
make sure you
read the the page on those.


M-Audio Audio Delta 1010 (8in/8out PC Card) |
| The Delta 1010 is an
audio interface that has 8 ins and 8 outs for connecting to a mixer.
The mixer's busses or direct outs connect to the Delta's inputs and the
Delta's outputs are connected to the mixer's line inputs. |
Types of Mixers
There are basically 3
basic types. 1)Analog Mixers and 2) Digital Mixers. There is a
3) new breed of analog mixers that have USB and Firewire interfaces
added. An analog mixer is comprised of analog signal paths and
does not convert the audio to digital data. A digital mixer accepts both
digital and analog sources. It converts analog waveforms to digital data as
soon as it enters the mixer, and usually has effects and processors that can
affect the data digitally before it converts the data back to analog waveforms
on the way out. The newest analog mixers have USB or Firewire interfaces
added. These usually have totally analog signal paths throughout the board and
may be used to output analog. However, individual tracks and the master output
may also be converted to digital to give you another option of getting
your audio to the computer. (You have to check specs to see exactly what goes
down the firewire or USB pipe. It may be different in each mixer.)
What's "Best?" Oh I knew
you would ask. Short answer: As always, it depends. We'll spend much of the
remainder of the class helping you decide what's best for you.
You can use a
mixer with an audio interface. If your mixer has enough channels, you
can also route the backend, that is, your audio interface's outputs
to the board and use the EQs and sends/returns to touch up and
polish the sound in the analog domain. This allows you to
separate vocals, drums and bass so you can have a real hardware fader to
move when mixing. This is the classic approach to mixing and it
has been used since the 60's. If you have an 8x8 audio interface then
you can have 8 separate channels at the board. An advanced studio
operator might have 24 channels streaming from the computer. With a
mixer, you gain flexibility, ease of patching in gear, and for many of
us, it's just more fun to have real faders and not stare into the
computer screen.
Mixers and Quality
Why do some Mixers
cost so much more but offer fewer features? Typically, in mixers, you
get what you pay for, and you really can't go by specs when it comes to
durability. Quality components cost money, so does rugged, reliable
construction. Keep in mind that mixers have many moving, mechanical parts.
If you are going to gig with a mixer, it has to be pretty solid. The
really inexpensive mixers often have less headroom, more hiss and
susceptibility to picking up hum, so you have to be real careful about
overloading it, wiring, and not EQ-ing as much. That is particularly true of
older, used mixers you might find at online auctions.
Who
needs to get a Mixer?
-
For the budget studio, people need mixers when they want
to add recording studio functions to their basic
soundcard which may only have two inputs and two
outputs.
-
For the more advanced studio, People need to have a mixer to
when they have lots of gear, like several MIDI synths,
mics, or want to use quality outboard gear like reverbs,
delays, compressors, pedals and other stuff that needs to be
routed to the computer or stand -alone multi-track
recorder.
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Today, however, the
sound quality of most mixers, even the budget Behringers, is very high, and
some say indistinguishable from mixers that cost 2-3 times as much. However,
the inexpensive mixer may have wobbly, sticky faders and knobs. Or it may
have had less than rigorous quality control at the factory where they were
built. A mixer is full of complex wiring and circuitry and if even one of
internal connections goes bad, it may be extremely difficult to fix.
Warrantees and repair policies may figure into the price of a quality
mixer.
There is also the
matter of microphone preamps, which have to boost the relatively weak
signal coming from a mic into useable line level signal. The cheaper the
preamp, the more garbage will be included in the final signal. Now if you
are just mixing synths (which are usually all at line level already, you
don't need mic preamps. But if you are wanting to record acoustic guitars
and vocals into your computer, you need good preamps. The Mackie's, for
example, cost more, but are built like tanks, sound excellent, are great
work surfaces, and they have their much hyped XDR preamps, which will not
let you down. You might think that the Behringers, due to their
inexpensiveness, might have bad preamps. However, they are in use in many
home studios, and people often remark in my forums how good they sound. As
people go more professional in their studios they typically get outboard
preamps to bypass the mixer's preamps.
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