22
NexLog Recorder User Manual v2.2.0
2.4.8. Connecting Telephone, Radio, and Other Analog Audio Signals to
the Recorder
This section applies to units equipped with one or more Analog Input Boards. If
you are not sure this board is installed, check the printed back-panel diagram
that was packed with your recorder.
WARNING
To reduce the risk of fire, use only 26 AWG or larger telecommunication
wire.
The Analog Input Board handles interfacing to analog audio signals. The
number of channels per board will vary depending on which is ordered. Eventide
sells 8, 16, and 24 channels versions of the Analog Board.
A mating connector is provided for each board unless a Quick Install Kit has
been ordered (see Section
2.4.9. The Optional Quick Install Kit
. The connector has
two rows of contacts. One row is numbered 1 through 25, and the other row is
numbered 26 through 50. Numbering is such that pin 1 is opposite 26, and 25
is opposite 50. Each audio input requires two wires, in what is known as a
“balanced” configuration. There is no “ground” connection. The channel and
connector pin correspondence is detailed in
Appendix D: Channel Wiring for
Eventide offers a Quick Install Kit that, besides pulling together the parts you
will need for a convenient installation, brings Channel 1 to the white-blue pair
(see Section
2.4.9. The Optional Quick Install Kit
To connect a telephone line to a given channel, simply connect the two wires to
the two pins for that channel. It is not necessary to check or observe polarity.
To connect an audio source such as the line output or recording output of a
radio, connect the “hot” lead to one pin and the ground or shield lead to the
other. Again, there is no distinction between input pins. Either can be connected
to the “hot” lead.
Any audio source may be connected, provided that the audio voltage is
nominally in the .1 - 1 Volt range and remains fairly constant. Differing voltage
levels are compensated for when setting up the board parameters from the
recorder front panel. Not recommended are sources with greatly varying levels,
such as “speaker” outputs. Also unusable are “microphone” signals, whose
levels are too low by far to be usable without pre-amplification.
2.4.9. The Optional Quick Install Kit
For each telephone recording board in the recorder, you will have received either
a mating blue-ribbon connector, or if ordered as an option, a Quick Install Kit.
The connections for the mating blue-ribbon connector are detailed in
D: Channel Wiring for Eventide Analog Input Boards
. The pins are numbered on
the connector itself for reference.
