mistakenly plugged in a standard power brick to a preamp,
which resulted in a fried one. You can avoid this mistake
by clearly marking your music power supply bricks to
distinguish them from your standard polarity bricks.
Computer Tools
Another industry standard that you’ll discover is
Digidesign’s Pro Tools. This software and hardware combination enables you to record and then manipulate sound
on your PC. There are numerous software options for both
PCs and Macs. For example, I use Logic Studio on a Mac.
However, Pro Tools is the entrenched standard. Regardless
of your computer hardware and software, you’ll need lots
of disk storage and, more importantly, high throughput.
Think fast terabyte drives. Expect to use 0.5 GB or more
for an eight-track recoding of a 10 minute song.
the signal chain. This can be accomplished by using a
3-to-2 pronged adapter. Some gear has a built-in ground
lift switch. There are obvious safety issues associated with
lifting the ground in an AC powered device. In short, don’t
allow your body to complete a ground fault circuit.
Continued on page 10
Cables
Cables and connectors for recording are specialized.
When selecting cable, think thick copper to minimize
resistance losses. Conversely, when you select high-impedance microphone and instrument cables, think shielding
for noise reduction and minimum capacitance per foot to
minimize high frequency loss. Bulky XLR and old-fashioned 1/4 inch still handle most of the audio
signals in a home or professional recording studio. While
on the topic of impedance matching, consider that
microphones, guitars, and other instruments typically
present a high-impedance output (15K–1M ohm) which is
much higher than the typical low-impedance line input to
an analog-to-digital converter. You'll need a preamp or a
direct box to compensate for the impedance mismatch
and assure the signal level is appropriate for your input
device. A direct box can be as simple as a transformer
with input and output connectors.
Signal Processors
Stand-alone, floor, and rackmounted signal processing options —
filters, amplifiers, and various effects
— can help you achieve the tone you
demand. At a minimum, you should
consider an eight channel virtual or
hardware mixing board. A mixer
allows you to adjust levels of various
inputs and combine them into a
single mono or stereo track. I prefer
the feel of a real hardware mixer over
a virtual mixer defined in software.
Ground
One of the headaches of
connecting a half-dozen amplifiers,
effect boxes, and computers together
is that you have to pay attention to
ground loops. Often, the only
practical way to remove 60 Hz hum
from the audio signal is to lift the
ground on one or more devices in
January 2009 9
