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invisity listen only earpiece

invisity by Phonak is the smallest in-ear radio receiver in the world and a globally popular listen-only ear prompter.

Comfortable to wear and offering excellent sound quality, this miniaturized listen only earpiece is perfectly suited to situations in which clearly received messages are vital and discretion and freedom of movement a necessity.

invisity is unique in the market and a popular ear prompter in the security arena (interviews/interrogations) and the broadcast world (performances/productions/speeches).

  • Ultra-discrete
  • Comfortable to wear
  • Programmable

Two invisity versions are available:

invisity flex

1 channel (7 MHz range), programmable via the optional invisity programming unit (IPU) or through a Phonak dealer.

invisity 4-channel

4 channels (7 MHz range). Supplied with invisity remote control (pictured left) for discrete channel flicking. Additional adjustable parameters.

fixed or programmable (single or multi), 7MHz band
Frequency response
200 Hz - 4500 Hz
Audio signal output 94 dBSPL measured in a 1.3 cc ear simulator (Volume 1 default setting), 102 dBSPL measured in a 1.3 cc ear simulator (Volume 2 default setting),
or adjustable on 4-channel model
Noise filter squelch
Sensitivity SINAD >17 dB @ E=3mV/m
Channel selectivity >50 dB (at 200 kHz channel spacing)
Antenna magnetic, integral
Spurious emissions below -57 dBm ERP
Distortion >5% (depends on volume setting)
Dimensions 19 x 12 x 12mm (0.74" x 0.47" x 0.47")
Weight 1.5 g (incl. battery)
Battery life 13 h (constant reception) using Phonak battery
Power consumption 3.3 mA
SNR (signal over noise ratio) approx. 41dB in the AGC @ 1 kHz

Several transmitter options exist for the invisity listen only earpiece.
These include:

Phonak TX300V
The TX300V is the ideal 9.5-inch transmitter for long range use with Phonak invisity. It features:Frequency range of 150-220 MHz 20 frequency settings 2 adjustable length radials Remote antenna with mounting bracket
The TX300V is fully programmable, fully resistant to temperature extremes and humidity, and available with PTT (with/without VOX function).

The inspiro transmitter is a comfortable, belt-worn FM device designed for use over short distances. It is available with a lapel- or face-worn mic, features 40 channels, runs for up to 13 hours, and does not require any frequency allocation.

EasyLink is a simple yet effective voice transmitter. It features a single Zoom microphone mode, an audio input, and can be held in the hand or hung around the neck.