The BTB65 TalkBox is a calibrated acoustic signal source designed for STIPA measurements and other speech intelligibility testing applications. It delivers standardized test signals through its built-in loudspeaker or via the line-out connection for use with external playback devices. An intuitive touchscreen interface makes setup and operation quick and straightforward in the field. The TalkBox features a wide loudspeaker frequency range of 20–15,000 Hz and outputs test signals at a standardized, calibrated sound level of 54–72 dB(A) at 1 meter, with the ability to increase or decrease the signal level to suit ambient environmental conditions. It is powered by an included external power supply and comes protected in a custom hard case for safe transport and storage.