CXM Technical
MANUAL
5
CS1 Stereo Music Module
2.01 This module contains RIAA equalised phono and line level amplifiers, sub-sonic
filter, equaliser, auxiliary sends, channel fader, crossfade assign, mono switch,
PFL select logic and remote start switch. Inputs are by way of gold plated RCA
phono sockets.
2.02 Input Amplifier Equalisation
Two input amplifiers are fitted. The RIAA equalised phono input has an input
impedance of 47k
Ω
, loaded with a capacitance of 220pF. The RIAA equalisation
is accurate to within
±
0.5dB 30Hz-20kHz. This input amplifier can be configured
internally with a 3 position jumper. The 3 input options are:
INPUT OPTION
DESCRIPTION
RIAA
For moving magnet cartridges.
Flat response @ 0dBu
For CD players and other ancillaries with outputs
compatible with an input range of-12dBu to
+12dBu
Flat response @ -10dBu
For low output ancillaries requiring an input range
of -22dBu to +2dBu. If this option is selected,
consider the possible risk of overload with
incorrect gain settings.
2.03 Input
Specification
The line amplifier is unbalanced with an input impedance of 47k
Ω
and a nominal
input sensitivity of 0dBu.
2.04 Input
Gain
The gain range for both input amplifiers is trimmed to
±
12dB with reference to
the centre (unity gain) point of the gain control.
2.05 Input
Select
The input select switch is positioned at the top of the module with LED status
indication. A provision to mark the fascia with input source details is adjacent.
2.06 Sub-Sonic
Filter
A permanent sub-sonic filter attenuates signals below 20Hz at a rate of
18dB/oct. This filter is positioned pre-equalisation thus preventing sub-sonic
signals being boosted by the bass control.
2.07 Equalisation
The equaliser has 3 bands, each band having a defined range resulting in a
controlled response outside the audio spectrum. In addition, the range of boost
and cut can be internally configured to operate at
±
12dB or limited to
±
6dB by
simply reversing a single circuit jumper. A second jumper can be used to bypass
the equalisation (see drawing).
The HF control operates at 10kHz, mid at 1200Hz and LF at 50Hz, all 3 controls
have a centre detent for positive neutral setting.
Factory default settings are
±
6dB with equalisation in circuit.
