The
last couple of years has seen the appearance of USB microphones
in the ranges of most microphone manufacturers. So what are
they and why do we need them? Today, USB (universal
serial bus) is part of the standard architecture of all PCs
and Apple computers and it's the commonest way to plug in a
range of peripheral gadgets direct into the computer, from external
hard drives and printers to your ipod.
The Plug
and play capabilities of USB allow devices to be connected
and disconnected without rebooting
the computer or turning off the device but the other great feature
of USB is that it can provide power for many low-consumption
devices so they will work without the need for an external
power supply.
It was inevitable then that eventually someone would come up
with USB microphones and infact the Samson CO1 was the
first affordable USB studio condenser mic to hit the market.
For the first time ever, you could record audio into you computer
by simply plugging the Samson direct into the USB port without
the need for XLR leads, in/out boxes, or expensive pre-amps.
The idea was simple and it opened up possibilities for anyone
recording audio from Podcasters, journalists, students,
and business people adding audio to websites and multimedia
presentations.
But of course the design of any mic means that it needs a preamp
to amplify its tiny electrical output signal up to line level
and if it's to be plugged direct into a USB port then
the mic will also have to house its own AD converter to turn
the analogue signal into a digital stream .
So basically these two elements have to be built into the body
of any USB mic and this leads to a couple of problems. Because
of construction constraints most USB mics don't have a variable
input and output so they are set to handle an optimal "fairly
loud" sound source without distorting. All well and
good but that does mean that quiet sources and even the spoken
word sometimes aren't loud enough to get a decent level. Add
to that a budget AD converter small enough to be built into
the microphone body and you have a pretty large compromise.
The manufacturers have put a lot of effort into designing their
USB microphones and all the ones I have tried sound pretty
good but they all suffer from the above problems to some degree.
Samson, on its improved version has a software switch to change
between 3 sensitivities lo/ med and loud sound sources
and if you are careful then you can get a decent recording without
too much noise.
Other manufacturers of USB microphones include sE, Blue and
now even some older big name manufacturers are producing USB
microphones with Shure's PG27 USB and AKG's Perception 120 and
these are now getting some good reviews on the forums but for
me the USB mic is very much an entry level idea for musicians
and the real arena for these mics is in ENG or podcasting where
ease and mobility are important. Ultimately the lack of flexibility
of using different preamps and even AD convertors will always
mean that these mics are never serious studio tools but if you
are one of the thousands of people starting out and are interested
in getting your ideas down quickly and cheaply with the minimum
of fuss they are undoubtably a great starting point mic.
OTHER
OPTIONS
CEntrance's
idea is to take the preamp and AD converter and build it into
a small in-line adapter that you can plug into the bottom of
any condenser mic. The CEntrance has variable gain and phantom
power as well as built in headphone monitoring and again is
proving very popular with the BBC and CNN etc for news
gathering and live location reports. I have used one a great
deal and think its a neat way of using a range of different
mics direct into the laptop.
Ultimately there is a need for musicians and particularly those
on a budget, to be able to use their mics creatively and flexibly
and by far the best option is to buy something like the Alesis
io2 which has everything that you need to interface any
mic with your computer. The io2 has two very nice, quiet preamps
with variable gain, adjustable headphone monitoring which you
can switch between direct and USB and a host of other features
including line inputs and insert points. All the stuff you actually
need to make music with your mics for under £100. So if
you are into music then by all means have a look at the new
USB mics but really you can spend your money a lot better by
buying a good USB interface like the Alesis. However if you
are just starting out and you want a good quality, easy to use
mic to record your voice or quick musical ideas while you are
out on the move then a USB microphone could be just the job.
