Sound Level Meter The XL2 provides together with the measurement microphone a precise sound level meter for monitoring of live sound events and environmental noise. For example parameters like actual, Lmin, Lmax, Leq are measured with frequency weighting A, C, Z and time weightings F and S at the same time. All measurement results are simultaneously available. Customers may log all acquired level information onto a removable Mini-SD card including real time information. Additionally the XL2 offers wav-file recording for a complete documentation of the measured sound pressure levels, as well voice notes might be added for each measurement. The accuracy of the XL2 exceeds IEC 61672-1, class 1. The XL2 measures correction values between the loudest point of the live event and the actual measurement positions according DIN 15905-5 and SLV 2007.

Extended Acoustic Pack (optional) The Extended Acoustic Pack offers additional features for sound level- and acoustic measurements: Percentiles: 1%, 5%, 10%, 50%, 90%, 95%, 99% Time weighting: Impulse Sound Pressure Level LIeq, Sound Exposure Level LAE Clock-Impulse Maximum Level (TaktMax) and values as specified in DIN 45645-1 Digital I/O interface Recording of WAV-files (24 bit, 48 kHz) High-resolution Zoom-FFT, up to 0.4 Hz resolution in the range of 5 Hz to 20 kHz Reverberation time RT60 in 1/3 octave resolution

Real Time Analyzer RTA The RTA perfectly suits tasks, such as optimizing of sound systems. In addition to the wideband parameters the XL2 measures in parallel the real time spectrum either in 1/1 or 1/3 octave-band resolution according IEC 61260 class 0.

FFT Analysis The real-time FFT is the ideal tool for visualization of comb filters and narrow band effects. It measures the actual level and the averaged level Leq from 7 Hz - 20 kHz in three ranges. The optional Extended Acoustic Pack offers an additional high-resolution Zoom-FFT up to 0.4 Hz steps in the frequency range 5 Hz - 20 kHz.

RT60 Reverberation Time The XL2 measures the energy decay in the range from 63 Hz to 8 kHz by the Schroeder method in 1/1 octave bands. Automatic triggering and averaging of multiple measurements simplifies the operation and minimizes the measurement time. As test signal serves either an impulse source or gated pink noise. The optional Extended Acoustic Pack extends the RT60 measurement to a 1/3 octave resolution.

Polarity Same polarities are important to match the left and right speaker for a stereo sound image. The XL2 measures the polarity of cables, single speakers and speaker cabinets. The detailed result page displays the measured polarity of the octave bands from 125 Hz to 8 kHz. This allows in-depth verification of the polarity - frequency relation. As test signal serves the polarity signal provided on the NTi Audio Test CD or the Minirator test signal generator.

Delay Time The delay function suits the accurate setup of delay line arrangements, thus the directionality of the signal source will be optimized. The XL2 measures the delay time between the electrical reference signal and the acoustical signal from the speaker. The required acoustical delay settings are displayed automatically, thus the audio engineer may set the measured delay time directly at the delay device in the rack.

Speech Intelligibility STI-PA (optional) The STI-PA function measures the speech intelligibility of public announcement systems according the latest revision of IEC 60268-16:2003 standard. The XL2 displays the measurement results as STI or as CIS results, accompanied by the individual levels and modulation indices of the seven octave bands. The measurement results are acquired from the dedicated STI-PA test signal, generated by the included STI-PA Test CD Minirator MR-PRO, test signal generator, required for audio systems with line inputs NTi Audio TalkBox, acoustic signal generator, required for audio systems with voice microphones, thus measuring the complete signal chain

Analog Audio Analyzer Together with the balanced XLR and unbalanced RCA inputs includes the XL2 a comprehensive audio analyzer. It measures simultaneously level, distortion (THD+N) and frequency. The internal loudspeaker or headphone output offers audible monitoring of the test signal or just listening to the residual distortion. The optimized low distortion and low noise design enable level measurements down to -112 dBu and residual distortions typically lower than -100 dB, which is unmatched in handheld instruments.

Scope The scope function visualizes the waveform of the electrical input signal. It automatically triggers to the fundamental frequency and selects the scaling of the X-axis (time) and Y-axis (level) accordingly. The fundamental or most dominant frequency is displayed above the scope screen.