Digital input levels 21Digital input levels 21Digital input levels 21
Digital input levels
Digital input signals entering the CBX-D5 cannot be level adjusted. This is the same for
most digital audio equipment, the idea being that once the level has been set during the
original A/D conversion it should not need readjustment. It also simplifies the interfacing
of digital audio signals between equipment.
The level of the audio signal output via the CBX-D5’s digital outputs, however, can be
level adjusted, and this is set by the controlling software.
Setting the analog input level
The recording level for analog input signals can be set using the CBX-D5’s ANALOG IN
LEVEL controls. These controls allows independent level setting for channels 1 and 2 and
they can also be used to balance the left and right channels of a stereo source connected to
the analog inputs. The maximum analog input level is +22dBm.
These controls should be used in conjunction with the input level meters, which are
described below.
Input level meters
Unlike analog tape recorders, digital audio recorders are very unforgiving when it comes
to excessive signal levels. Digital audio signal clipping normally produces unpleasant
distortion, pops, and clicks, and unless you have some very sophisticated editing
equipment it is impossible to remove it after the event. So great care must be taken when
setting the recording level.
With a digital audio recorder such as the CBX-D5, noise and hiss produced by setting the
recording level too low is not a problem. However, setting the recording level too lo w will
reduce the effective dynamic range of the recording and with a dynamic range of 96dB*
available it makes sense to use as much of it as possible.
Basically, the recording level should set so that the loudest signals light the –3, –6, –9
LEDs, but never light the CLIP LEDs. When recording with microphones, where sudden
signal increases are possible, it may be worth having a “dry run” before you hit the record
button. A compressor is a useful tool when recording vocals and acoustic instruments.
Headphone monitoring
During recording and playback, the four audio channels can be monitored using a pair of
stereo headphones. Headphones should be connected to the PHONES jack on the front
panel. The volume can be adjusted using the PHONES VOLUME control.
As you can see from the diagram below, channels 1 and 3 appear in the left speaker and
channels 2 and 4 in the right speaker.
* 96dB is the dynamic range available with a 16-bit digital system (6dB per bit).
Channel 1 RL Channel 2
Channel 3 Channel 4