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The TalkBox is an acoustic signal generator for speech intelligibility measurements in evacuation and announcement systems, as well as for level alignment of teleconference and other audio systems. It allows for the complete end-to-end evaluation of the speech intelligibility STI-PA from the talker’s microphone to the listener’s ears. The TalkBox provides the test signal simulating a human talker at 60 dBA @ 1 meter according to IEC 60268-16.

The TalkBox features human head-like dimensions and is based on a solid-state-generator. It replays the STI-PA test signal at the precisely correct playback sampling rate, also ensuring best performance through the internal amplifier and the precision loudspeaker. A variety of supplied or user-defined test signals may be precisely output for different alignment applications.

NTi Audio TalkBox Features
  • Individually Equalized

NTi Audio TalkBox includes a precise broadband loudspeaker. Perfect flatness of ±1 dB over the relevant frequency range is achieved by individual equalization and calibration using advanced FIR filtering and DSP technology.

  • Adjusted Output Level

The IEC 60268-16 standard specifies a sound pressure level for a speaker simulator of 60 dBA at 1 metre distance. The TalkBox output levels are calibrated to comply with this standard and there is no volume control fitted.

  • Lombard Effect

The human voice tends to be raised in level in emergency situations, the so called Lombard Effect. In order to cope with this effect, all STI-PA related signals are additionally offered at an increased level of 70 dBA at 1 metre.

  • Balanced Line In / Out

Using the balanced line out, the TalkBox operates as a signal generator. Sampling frequency deviations - a problem when using portable CD players for STI-PA measurements - are completely eliminated.

Any external signal can be connected to the system using the balanced line input. The applied signal is transparently looped to the line output and processed in the internal DSP in real-time to appear equalised at the speaker.

  • Different Test Signals

The TalkBox also generates additional wave forms: White noise, pink noise, sine wave, reference speech signals and the delay time measurement chirp. Custom designed signals may be loaded onto the CF Card and are seamlessly looped.

  • Mic Stand Mount

Typically the NTi Audio TalkBox is positioned on a conventional mic stand in front of the speaker microphone; at exactly the position of the actual human speaker during announcements. The TalkBox features a mic stand mount on the bottom plate.

  • Remote Mute

The TalkBoxFor incorporates a remote mute function operated by any external switching device connected to the mute input. Useful for STI-PA measurements in large buildings.

  • Universal Power Supply

The TalkBox supports a power supply range 10 - 18 VDC. An external power supply for worldwide operation is included. Alternatively the optional battery pack may be used.

Product code: TALKBOX :: NTI 600 000 085 TalkBox Acoustic Generator £POA

Calibration Certificate

Although the TalkBox is factory calibrated before despatch it is not routinely supplied with a calibration certificate but one may be bought if required.

Product code: TALKBOX-CAL-CERT :: NTI 600 000 018 Calibration certificate purchased with TalkBox £POA
Product code: TALKBOX-RECAL-CERT :: NTI 600 000 028 Recalibration of TalkBox and certificate £POA

Battery Pack

The lightweight Lithium Ion battery with a nominal capacity of 39Wh serves as a portable power source where no AC-mains connection is available. After charging the battery for approximately 6 hours, the stored energy typically drives the NTi Audio TalkBox with:

  • STI-PA signal in Lombard mode (loud): 7.5 hours
  • STI-PA signal in normal mode: 12 hours
  • Idle mode, stand-by or line out: 15 hours
Product code: BATTERY-PACK :: NTI 600 000 086 Battery pack for NTi TalkBox £POA