- How many simultaneous tracks can I record?
Most modern 4-tracks will handle 4 at once; lower end systems only
operate with a single stereo bus, and can therefore handle only two at
once. Consider how many people you might have playing at once.
For example, I work with one other guy (I suppose two is too small a
number to constitute a 'band' :-); both usually play guitar. Thus,
since the synth backing (all the MIDI) comes in as two tracks
(stereo), we need to be able to record 4 tracks as well so that the
two guitars each get a track of their own.
- Does the 4-track machine run at double speed?
This is probably almost mandatory in a quality 4-track these days.
However, if you want to play normal cassettes in it, or record for
replay in a normal deck, then you need the ability to run at normal
speed.
- Does the 4-track machine have appropriate noise reduction?
If at any time you want to record onto a cassette to be played back on
a normal deck, you need to consider that normal decks will not have
DBX, only Dolby, so you either use no noise reduction, or Dolby.
See also Q1.1.3.
- Is noise reduction controllable per track while recording?
If you are using MIDI and tape sync you need to ensure that you can
record sync with no noise reduction on one track (usually 4) and get
it back out without hearing it in the mix. Usually track 4 can have
the noise reduction switched on or off separately.
- Does it have an outboard FX (effects) loop; can you use it to do
most (if not all) of your mixing, or will you need an outboard mixer?
- If you're mixing with it, what eq does it have?
Most 4-tracks will have some form of eq; it may be per channel or a
stereo graphic that covers all the tracks. If you're trying to keep
one instrument per track, will the eq allow you to affect just that
one track? If eq is a real issue, you need to look at some sort of
external mixer.
- Will the inputs switch from mic to line level?
Signals are classified into (roughly) two sorts, based on the voltages involved: 'mic level' signals are lower voltage, typically seen from microphones (of course) and electric guitars; 'Line level' signals are higher voltage, typically seen from synths, hi-fis (??), etc. (??)
NOTE: Guitars can provide a hell of a signal if played heavily!
Most 4-tracks will at least have a 'line / mic' switch on the input.
Some have a slider to allow the best matching to be selected.
It's important to get this right: you can connect a mic level signal
to a line level input and hear the sound by turning the volume up, but
you'll also turn up the noise. Similarly, you can put a line level
signal into a mic level input and turn the channel down, but you may
overload the input and cause distortion.
Typically, you want to see a good strong (but not distorting) signal
when the input channel is a 80% or so of maximum volume. With a
slider to set the input impedance, you can get the best 'match'
between instrument and 4-track.
tstrohma@theodolite.ae.calpoly.edu (Trevor Strohman) writes:
Line levels come in two types: -10 dB and +4dB. Consumer equipment is
usually -10dB and pro equipment is -10 or +4. Usually the difference
between the two types is small enough that the gain control on the
mixer/4-track can handle the difference.
For a 4-track studio, +4 signals almost are never come across.
Examples of consumer line level equipment include tape decks, CD
players, and synthesizers. Record players are _not_ line level and
require a preamp. Their voltages are comparable to microphone levels.
Electric guitars are tricky, because they are usually stronger in
voltage than a microphone and yet lower than a line-level signal. Use
the gain knob wisely.
Typical voltages for these signals are roughly 1 volt for line level
signals, and maybe 100 millivolts for a microphone (depends on the
microphone type).
Remember to give yourself plenty of room to mix. Often I see people
with the volume sliders all the way up. This gives no flexibility.
If you have input gain knobs, play/sing at a normal level through all
sources and adjust so that there's equal volume coming out at equal
slider positions, and so that you don't have to push the slider too
high to get a good amount of volume. Now you have total flexibility
to mix with.
