AVComm

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Revision as of 15:40, 5 April 2011

AVComm has some of your audio-visual needs. If you have any questions on how to setup something up, let us know at ec-avcomm@mit.edu.

Current Officers

• Ben Lehnert - 5E
• Gabriel Karpman - 5E

Inventory

Portable/Party Equipment

• 2x JBL MR835 Loudspeaker (3 way, 8 Ohm, 250W RMS/100W peak (pink noise), 38Hz-20kHz)
• 2x CSX35-S2 Loudspeaker (2 way, 8 Ohm, 150W RMS/375W peak, 60Hz-18kHz)
• 1x QSC USA900 Amp (450W/channel; 4 Ohm per channel/8 Ohm bridged mono)
• 1x Crown Power Base-2 Amp (400W/Channel; 4 Ohm per channel)
• 1x MX1400-DSP Mixer (4x stereo RCA in, 2x 1/4"TS/XLR hybrid mic in, 1x 1/4" TS mic in; house and rec RCA out, house and booth XLR out)
• 1 DMX Dimmer

Talbot Lounge

• HD Television
• Projector
• 1 Phillips Surround Sound Receiver w/ DVD Player & iPod Dock
• VCR
• HDTV Tuner for Projector

Recommended Speaker Configurations

• Standard party speakers: MX1400 house out --> USA900 in STEREO --> JBL MR835s on left/right channels
• Mono Amp/Quad Speakers: MX1400 house out --> USA900 in STEREO -->
  • JBL MR835s in parallel on channel 1[2]
  • CSX35s in parallel on channel 2[1]
• Bi-Amp/Quad Speakers, no crossover: MX1400
  • house out --> USA900 in STEREO --> JBL MR835s on left/right channels
  • booth out --> PB2 in BRIDGE MONO --> CSX35s in parallel as directed for bridge mono
• Bi-Amp/Quad Speakers with crossover: MX1400 house out --> 2-way crossover
  • low-pass crossover at max --> USA900 in STEREO --> JBL MR835s on left/right channels
  • high-pass at selectable --> PB2 in BRIDGE MONO --> CSX35s in parallel as directed for bridge mono
• Bi-Amp/Bad Ideas Subs: MX1400 house out --> 2-way crossover
  • low-pass crossover at selectable --> PB2 in BRIDGE MONO --> Bad Ideas Sub as directed for bridge mono
  • high-pass crossover at selectable --> USA900 in STEREO -->
    • JBL MR835s in parallel on channel 1[2]
    • CSX35s in parallel on channel 2[1]

When driving both the JBL MR835s and CSX35s off the same amplifier, put the JBLs together and the CSX35s together, and use individual channel gain control to prevent overdriving either pair (mixing JBLs and CSX35s on the same channel will either overdrive the CSX35s, or prevent full utilization of the JBLs)

Note that the USA900 is rated to handle 8 Ohms on bridge mono, while the PB2 is rated to handle impedances as low as 2 Ohms in bridge mono configuration (both can accept impedances of 4 Ohms and above per channel in stereo configuration)

If you don't understand what part of your desired configuration means, ask someone who does before your event.

Equipment Lending Policy

If the EC sound system is used for a hall party or other hall event, it must be returned to the AV closet in Talbot within two days of the event unless there is another event scheduled by a different hall within those two days, in which case it must be returned to the AV closet or transported to the other hall at least two hours prior to the other event. If a hall doesn't comply with the first of these two conditions, they will be fined $25.00 a day for each day that the equipment remains on the hall after the two day grace period. If another hall event is within the two days, the hall hosting that event gains responsibility of the system.