background image

Mode 2

All

Priority Pre-select switches 

Down

In this mode, only one mic at a time can be “on.”  The lockout bus shuts down all other mics until
the first speaker pauses. As soon as the controlling microphone goes silent, the lockout bus goes
inactive and any other mic can come on. This switching takes place without any 
syllable-grabbing delay, or pops or clicks. (This mode is known as “First-come-first-served” 
or “Filibuster.”)

This mode is very useful when the gain setting of the overall sound system must be close to the
threshold of feedback, and additional microphones coming on could throw the system into feed-
back. The SmartMixer will not allow multiple microphones to be on at the same time in this mode.
The switching is so fast and silent that the meeting can still be completely interactive.

Mode 3

One

Priority Pre-select switch 

Up

The selected priority microphone can come on at any time and can mute any other mic that is on
(popularly called “The Chairperson” mode).

(Note that there may be special circumstances where two or three mics could be set to priority,
so those speakers could talk whenever desired, but still mute one or two non-priority mics.)

If multiple SmartMixers are used with AT8325/1.0 Link Cables, Priority Pre-select switches on all
channels in use will have the control effects described above.

The selected priority microphone(s) will mute only those non-priority microphones within the
same unit.

Preamplifier Gain

The SmartMixer has a substantial gain range, allowing it to accept a wide variety of

micro-

phones. However, if in some instances higher-output microphones are used for close talking, it
may be necessary to reduce the preamplifier gain. This can be done by changing switch settings
inside the unit. With the unit unplugged, remove the two screws on each side of the unit and
remove the top cover. Locate the internal switches designated on the circuit board by “S103,”
“S203,” “S303” and “S403” (Figs. 3 and 4, page 8). Changing the settings of these internal
switches will cause a gain reduction of 10 dB for channels 1, 2, 3 and 4 respectively. 

The preamplifier gain may be reduced further, allowing the SmartMixer to accept line-level
sources. Changing the settings of the internal switches designated by “S101,” “S102,” “S103”
and “S104” will cause an input reduction of 50 dB for channels 1, 2, 3 and 4 respectively. Note
that the appropriate internal switches can be used in combination for a total sensitivity reduction
of up to 60 dB for each channel. 

Output Gain

The SmartMixer’s output is factory set at line level. Should mic-level output be desired, simply
unplug the unit, remove the top cover and locate the switch on the circuit board marked “S501”
(Figs. 3 and 4, page 8). Changing the setting of this switch will cause a 50 dB reduction in output.

Phantom Power

Each of the SmartMixer’s inputs su12V DC phantom power. Should it be required to dis-
able the phantom power, simply unplug the unit, remove the top cover and locate the switches
designated on the circuit board by “S102,” “S202,” “S302” and “S402” (Figs. 3 and 4, page 8).
Changing the settings of these switches will disable phantom power on channels 1, 2, 3 and 4,
respectively. Note that, although they do not require phantom power for operation, most bal-
anced-output dynamic microphones can be used without disabling the SmartMixer’s phantom
power.

7

Содержание AT-MX341b SmartMixer

Страница 1: ...Microphone Mixer Installation and Operation Lockout Manual Priority Pre select 1 2 3 4 20 10 6 3 0 3 6 Output Level Master Threshold Master Level Gain 1 Gain 2 Gain 3 Gain 4 Power AUTOMATIC MICROPHONE MIXER AT MX341b Selected Channel ...

Страница 2: ... 1 This device may not cause harmful interference and 2 this device must accept any interference received including interference that may cause undesired operation Caution for FCC You are cautioned that any changes or modifications not expressly approved in this manual could void your authority to operate this equipment Note This equipment has been tested and found to comply with the limits for a ...

Страница 3: ...o are carried between mixers by the link cable The result is that all microphones on a multi mixer system can be controlled by one micro phone connected to any mixer Since all of the mixers are independently powered there is no practical limit to the number of SmartMixers that can be daisy chained Features To custom tailor conferencing needs the mode of each microphone channel can be independently...

Страница 4: ...n assigns the respective channel priority over the other channels A priority channel can not be locked out by other channels Any combination of priority non priority selections is allowed 7 Master Level control Normal setting is fully clockwise full output If reducing the mixer s output is necessary carefully turn the control counter clockwise as needed with a small screwdriver Once set as desired...

Страница 5: ...tput Can be changed to mic level output via internal switch see page 7 XLRM type connector 5 Inputs Balanced microphone inputs for low impedance dynamic or condenser mics Can be changed to line level inputs via internal switches see page 7 XLRF type connectors Figure 2 Rear panel 5 Link In Link Out Output Input 3 Input 2 Input 1 12V AC 15 18V DC Control Voltage Out 1 GND 2 3 4 Input 4 Lockout Manu...

Страница 6: ...shold control fully counterclockwise In this mode the unit will behave like a conventional four channel microphone mixer all automatic functions are bypassed 12 The Master Level recessed control on the front panel may be adjusted with a small screwdriver if necessary This control is at the last stage in the mixer and does not affect microphone gain threshold setting or meter indication Priority Mi...

Страница 7: ...stances higher output microphones are used for close talking it may be necessary to reduce the preamplifier gain This can be done by changing switch settings inside the unit With the unit unplugged remove the two screws on each side of the unit and remove the top cover Locate the internal switches designated on the circuit board by S103 S203 S303 and S403 Figs 3 and 4 page 8 Changing the settings ...

Страница 8: ...B VR202 VR302 and VR402 control off attenuation for channels 2 3 and 4 respectively Figure 3 Internal view of mixer Figure 4 Detail of internal controls Don t Touch Rear Panel Output Level LED Meter The Output Level LED meter is factory set to indicate RMS output Should peak output indication be desired simply unplug the unit remove the top cover and change the setting of the switch designated on ...

Страница 9: ...Out goes high 4 VDC This signal can be used to light indicator lamps switch speaker zones on and off select video cameras etc The control voltage should not be connected directly to an inductive load such as a relay coil as dam age to the mixer may result Several interface circuit possibilities are shown in Figure 5 Figure 5 Control interface examples 9 ...

Страница 10: ... to the unit When using more than one SmartMixer in a system it may be advantageous to mount two mixers in a 1U rack space This can be accomplished using the two short rack ears and an optional joining plate Model AT8628 which allows two units to be con nected side by side in a single rack space Security Caps For permanent installations where microphone selections positions and acoustic conditions...

Страница 11: ... DC either polarity 300 mA Operating Temperature 32 to 104 0 to 40 C Dimensions 8 25 210 mm W x 9 38 238 mm D x 1 75 44 mm H including feet knobs and connectors Weight 3 1 lbs 1 4 kg Included Accessories AC adapter AT8325 1 0 Link Cable Optional Accessory AT8628 Double Rackmount Joining Plate In the interest of standards development A T U S offers full details on its test methods to other industry...

Страница 12: ...P52324 2011 ...

Отзывы: