The hand-held instrument has an LCD showing menu options and measured values. It can be used with the rechargeable Lithium-polymer battery supplied for up to four hours. Dry cell batteries will give a similar life, or a external power supply can be used, which will charge the Lithium polymer whilst in operation. An XLR connector on the top offers a high-impedance, balanced connection for the audio input, with 48V phantom powering available for a microphone. Detection of NTI Audio M4261 or M2211 microphones is automatic. An RCA (phono) socket takes unbalanced signals. A 3.5mm headphone socket provides for monitoring the incoming signal. A microphone is built-in, which may be used for polarity and delay measurements as well as voice note recording to a Mini SD card, not supplied, up to 2GB, which can also be used to record screen shots, log measurements and to record WAV files, AD-PCM compressed as standard, but to 24-bit 48kHz quality with the Extended Acoustic Pack option. There is an internal speaker; a USB interface may be used for recharging the internal Li-Po battery as well as transfer of data.
The XL2 has a flexible user interface; the measurement screens may be personalised and ‘only a limited subset of the comprehensive functionalities enabled for simplified operator interfaces. Advanced users may access all menus, settings and store their preferred measurement configurations’. For basic users the XL2 offers ‘audio and acoustic analyser fixed operator interfaces with specific pre-defined settings. The XL2 boots up with exactly the required measurement parameters according the pre-defined instrument configurations. This ensures accurate measurements achieved by advanced and basic users.’
- IEC 61672, IEC 60651, IEC 60804, IEC 61260
- China: GB/T 3785:2010, GB/T 3241, GB 3096-2008, GB 50526, GB-T_4959-1995
- Germany: DIN 15905-5, DIN 45645-2, optional: DIN 45645-1
- Japan: JIS C1509-1:2005, JIS C 1513 class 1, JIS C 1514 class 0
- Switzerland: SLV
- UK: BS6698, BS5969
- US: ANSI S1.4:2014, ANSI S1.43, ANSI S1.11:2014
- SMPTE ST 202:2010, ISO 2969:2015
- SPL actual, Lmin, Lmax, Lpeak, Leq, gliding Leq
- Frequency weighting: A, C, Z (=flat) simultaneously
- Time weighting: Fast, slow and optional impulse simultaneously
- Correction values k1, k2
- Indicators show when sound level limits are exceeded
- Digital I/O interface for the control of external peripherals
Logging and Reporting
- All levels simultaneously
- Short-time levels including spectrum for 1 second or longer
- Wav-file for listening (compressed)
Real Time Analyzer RTA
The RTA perfectly suits tasks such as optimization of sound systems and rooms. The XL2 measures and logs wideband values and the real time spectrum in 1/1 or 1/3 octave-band resolution according to IEC 61260 class 0. The sound level meter results of the wideband and RTA spectrum are simultaneously available. Frequency weighting: A, C, Z (=flat). Time weighting: Fast, slow and optional impulse.
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 in three ranges over the entire audio band. 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 and adds the linear audio recording (24 Bit, 48 kHz). The Spectral Limits Option extends the FFT Analysis with trace capturing, relative curve display and comprehensive tolerance handling.
Reverberation Time RT60
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. Use either an impulse source or an interrupted pink noise as the test signal. The optional Extended Acoustic Pack extends the reverberation time measurement to a 1/3 octave resolution.
For a stereo sound image, it is important to match the polarities of the left and right speakers. The XL2 measures the polarity of cables, single speakers and speaker cabinets. The detailed result page displays the measured polarity as octave bands from 125 Hz to 8 kHz. This allows in-depth verification of the polarity - frequency relation. The polarity test signal is provided by the NTi Audio Test CD or the Minirator test signal generator.
The delay function supports the accurate setup of delay lines and thus the optimization of the directionality of the signal source. The XL2 measures the delay time between the electrical reference signal and the acoustic signal from the speaker. The required delay settings are displayed automatically, allowing the audio engineer to set the measured delay time directly into the delay device in the rack.
Analog Audio Analyzer
Level RMS / THD+N
The XL2 with balanced XLR and unbalanced RCA inputs offers a comprehensive, high performance audio analyzer. It simultaneously measures balance, level, distortion (THD+N) and frequency. The internal loudspeaker or headphone output offers audible monitoring of either the input signal or just 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.
Spectral audio measurements are offered in the units Volt, dBu and dBV within the following measurement functions: Sound Level Meter (1/3 and 1/1 Octave), FFT, 1/12 Octave (optional)
The scope function visualizes the waveform of the electrical input signal. It triggers to the fundamental frequency and selects the scaling of the X-axis (time) and Y-axis (level) automatically. The fundamental or most dominant frequency is displayed above the scope screen.
Included accessories: Test signal CD, USB cable, Li-Po battery, hand-strap, operating manual.
Optional accessories: As listed below.