MultiPhones II is a multi-user headphones system for broadcast studio, professional audio, and similar applications. It provides independent stereo headphone listening facilities with Zoned Talkback for multiple users. The MultiPhones II system consists of the Master unit and up to 12 satellite Guest Pods which are interconnected using standard CAT5 cabling.
The MultiPhones II Master unit distributes Program audio to all Guest Pods via three outputs. Although the Program audio is identical, each output is an isolated Talkback zone. Guest Pods can be connected to the three Talkback zone outputs in
any combination. The zones are addressed via the three Talkback buttons on the front of the Master unit. This allows a producer or call screener to communicate with Guest Pod listeners in each zone, e.g., "Host", "A-Guests", or "B-Guests".
The MultiPhones II Master unit has inputs for stereo Program audio, Talkback audio, and remote Talkback control. Master Level trimmers for Program and Talkback allow the user to preset maximum levels. The Zoned Talkback system
allows a producer or studio engineer to speak to Guest Pod listeners in each Talkback zone, overriding normal Program audio with Talkback mic audio. The Talkback function can be remotely controlled. Three RJ45 jacks are provided to
distribute audio and power to the Guest Pods.
Each Guest Pod contains a stereo headphone amplifier, volume control and headphone jacks. Both 1/4" and 1/8" (3.5mm) jack are provided. A pair of (parallel) RJ45 jacks on each Guest Pod permit multiple units to be "daisy chain" connected to each Master unit output. As a convenience, each Guest
Pod has a "cough button" and "mic-on" LED that can be wired to the user's audio console or other equipment, although these functions are not part of
the MultiPhones II system per se.
The MultiPhones II system is optimized for use with contemporary highefficiency headphones with impedances between 24 and 600 ohms. Because
each Guest Pod contains its own amplifier, any combination of different headphones can be used. There is no interaction between units, and no degradation of audio performance regardless of the number of Guest Pods used. The system uses low-Z balanced audio distribution so that long cable runs do not affect audio quality.
The MultiPhones II Master unit is powered with a built-in AC power supply. It is 1/3 rack width and can be rack-mounted with the optional rack-mount
shelf, or cabinet or wall mounted using optional cabinet/wall mounting brackets. The Guest Pods can be flush-mounted in a tabletop cutout, or mounted on a desktop or to a cabinet using the included desk-mount chassis.
Technical Specifications, Complete System
- Program Input -15 to +0 dBm, stereo, 10K bal / 5K unbal
- Talkback Input Either bal. mic or line, switchable, mono
- Frequency Response 5Hz - 20 kHz, +/- 0.25 dB
- Distortion .005% typical
- Noise -80 dBm
- Outputs For 24-600 ohm headphones
- Talkback control Contact closure (GPI)
- Power Requirement* 115/230 VAC, 50-60 Hz, 8W
- Approvals* City of Los Angeles Elect. Test Lab, CE
- Construction* Steel enclosure
- Physical, Master unit 5.75"w X 5.50"d X 1.60"h, 3 LBS
- Physical, Guest Pod 4.00"w X 3.00"d X 2.25"h, 1 LB
- Cut-out, Guest Pod 3.75"w X 1.75"h
