between the mixer and the optional expander unit(s), if used; and which shall be designed to mate with the connectors on the expander ribbon cable provided with each Expander unit.
16.PHYSICAL CONFIGU- RATION. The mixer shall have a steel chassis frame painted
17.OVERALL MINIMUM SPECIFICATIONS. In ad- dition to specifications previously cited, the mixer shall meet or exceed the following performance criteria: Noise. (20
Total Harmonic Distortion. (1 kHz @ +14 dBu,
20Hz–20 kHz.) Channel input to any output, below
.0025% typical. Attenuation (1 kHz @
0dBu. 20
+0 dB/–1 dB. 10 Hz to
100kHz, +0 dB/3 dB. Maximum Levels. Mic preamp input, +14 dBu. All other inputs, +22 dBu. All outputs, +22 dBu.
Impedances. Mic preamp input, 2.5 kΩ. All other in- puts, 10 kΩ. All outputs, 120 kΩ.
Equalization. Lo EQ Shelving @ 80 Hz, ± 15 dB. Mid EQ Peak @ 2.5 kHz,
±12 dB. Hi EQ Shelving @
12 kHz, ± 15 dB.
Microphone Preamp. E.I.N. (150 Ω terminated, maxi- mum gain), –129 dBm.
18.DESIGNATION. The audio mixer shall be a Mackie Designs LM-3204.
LM-3204E Expander
19.GENERAL CONFIGURATION. The expander unit shall not be designed to operate alone, but in conjunction with a Mackie Designs
1through 4 shall each be fitted with left and right insert jacks.
Additionally, the expander shall include 4 stereo effects return inputs.
20.POWER SUPPLY. All necessary operating voltages for the expander shall be provided by an internal shielded power supply.
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21.INPUT CHANNEL CONNECTIONS. Each expander input channel shall have a left and a right electronically balanced line- level input, accommodating a nominal line level of between
22.INPUT CHANNEL LEVEL AND ASSIGNMENT CON- TROLS AND INDICATORS. Each expander input chan- nel shall be equipped with a rotary dual gain control, a solo switch, a mute switch which also functions as an assignment switch to the alternate output channels, and a stereo balance control. Additionally, any soloed channel(s) shall have their
23.INPUT CHANNEL EQUALIZATION. Each expander input channel shall be equipped with a stereo equalization function. The equalizer shall have three sections: a
knee set at 80Hz and a range of ± 15dB; a
width of 2 octaves and a range of ± 12dB; and a high- frequency shelving equalizer
with the knee set at 12kHz and a range of ± 15dB.
24.INPUT CHANNEL AUXILIARY SENDS. Each expander input channel shall have one stereo
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