Connnercial Acoustic Measurement Systems


Name: CLIO 3.1

Computer : MS-DOS

Disiributor: Audiomatica S. R. L.

Agent: ORCA Design and Manufacturing Corp.

W. A. R. Audio (Australia)

Price: US$1595

Description: CLIO works as a precision 16-bit sigma-delta A/D and D/A audio analyzer, and is capable of generating any pre-defined stimuli such as sine, square wave, bursts, noise, and MLS (Maximum-Length Sequence). It is capable of measuring signals in both the time and frequency domains, and has a wide range of programmable output attenuations and input gains. The CLIO board is a half-length PC card that can be directly connected to a microphone or a separate (optional) battery powered preampl ifier, which can perform A-weighting filtering or drive long cables. CL10 performs real measurements of acoustic phase, with the facility to zero the received signal' s group delay. CLIO executes steadystate sinusoidal analysis with digital filtering of the input signal to achieve high noise immunity. CLIO is capable of measuring/performing: FFT of input signal with THD analyzer, THD with burst signals, electrical and acoustical phase, anechoic transfer function, MLS analysis of linear systems, system impulse response, energy time curve (ETC), cumulative spectra decay(waterfall plot) ) sinusoidal steady-state transfer function, near-field response, impedance function, loudspeaker Thiele-Small parameters, real time 1/3 octave analysis, generation of predefined waveforms, time signal display (oscilloscope), measurement of inductance and capacitance values, amplitude measurements in SPL, dBV, dBm. and volts. The results of each measurement can be saved in a file and can be recalled for subsequent analysis. overlaid plots are also available. Measurement files can be exported to loudspeaker CAD programs such as CALSOD and LEAP. Audiomatica has both an email address and a Web page (see their address details for full information).

Name: DAAS 3L

Computer : MSDOS

Distributor: ADM Engineering

Agent: old Colony

Price: US$995

Description: The DAAS 3L consists of a 16-bit card, associated software, calibrated microphone and documentat ion. St imul i include: sine wave, tone burst, pink noise, MLS, white noise, periodic noise, and chirp. It uses a 16-bit A/D and D/A converter, with sampling rates of 48kHz and 6kHz, 16384 maximum sample length, and FFT lengths from 512 to 4096 points. Frequency range: 15-20000Hz high, 5-2000Hz low, maximum frequency resolution 0. SHz. Measurement facil ities include: frequency response, phase response, group delay, harmonic distortion, intermodulat ion distortion, TIM distortion, impedance response, Thiele-Smal1 parameters, inductance and capacitance, oscilloscope function, energy time curves, smoothing, and waterfall spectrum plots. Input/output: lx line out, lx line in, lx mic.


Name: DSA 11 - Digital System Analyzer 11

Computer : MS-DOS

Distributor: ADM Engineering

Ageni: 0ld Colony

Price: US$7995

Description: The big brother to DAAS3L, DSA 11 is made up of a converter PCB, associated software, front-end hardware in a rack mount chassis, and illustrated manual. Measurement functions and features: signal conditioning and measuring by 16-bit D/A and A/D converters, transfer function and impedance response, calculation of phase response with automatic correction of signal propagation time, group - delay, step response and waterfall plots, distortion measurement as a function of frequency, distortion measurement with external signals, IM, TIM/DIM, and difference frequency distort ion measurements, maximum frequency resolution 0.5Hz, export files for use in speaker CAD programs.


Name: Liberty Aids Software

Computer: MSDOS

Price: US$2 0

DiSiribuior: old Colonv S0und Lab

Programmer: G. R. Koonce

Description: These programs and files work with IMP and Audiosuite audio measurement systems. IMPSPACE designs anechoic test layouts. IMPR00M designs near field and far field test layouts. IMPZOBEL designs simple and comple& Zobels based on input ZMA files. IMPPCOEO (Passive Crossover and Equalizer) places a fourbranch network ahead of the system defined by FRD and ZMA files. IMPEOLZR designs downslope equal izer functions used with. FRD files. Three datafiles are supplied for use with IMPSPACE.


Name: Liberty Audiosuite (software)

Computer : MSDOS

Distributor: Liberty instruments inc

Agent: old colony Sound Lab, Marton Music

Designer: Bill Waslo

Price: US$269 Audiosuite software with printed user' s manual.(a US$30 discount is available for IMP/M owners.)

US$69 Mic/Probe Preamp Kit, including case.

US$99 Assembled Mic/Probe Preamp Kit.

US$13 Highimpedance Test Probes Assembled.

US$23 Calibrated Mic Caosule and Leads.

US$129 Housed microphone capsule, calibrated, with holde (for use with IMP or the Mic/Probe Preamp).

US$179 Echo/DSP Sound Card, modified for better low-frequency response, with bundled software (Soundlmpress ions and drivers) .

Description: The Liberty Audiosuite is a component test system capable of measuring frequency/transient response, impedance, distortion, and spectral energy. Features include dual chpnnel MLS testing, cepstral analys is, gated s inewave testing for high dynamic range results at user chosen frequency points, steady state sinewave testing including measurement of harmonic distortion components as low as 0.03% with distortion versus frequency plotting, high purity multiprecision programmable signal generator, impedance measuretuents al low analys is of electronic components and automatic determination of loudspeaker Thiele-Small parameters, energy versus time displays for acoustical analysis of rooms and speakers, dual channel oscilloscope function with moveable markers, waterfal1 plots of cumulative spectral decay for resonance investigations, powerful data conversion faci 1 ities provide convers ion between FFT-derived data (constant frequency increments) and log frequency fortuat spacing or map data to user-defined frequency 1ists; programmable automatic operations for efficient research testing or cost effective production testing, choice of 13 sample rates up to from 5.5kHz to 48kHz with digital/analog anti-aliasing filtering, acquisition sizes of up to 16383 points, ASCll data export for compatibility with popular design and simulation packages, 2-channel 16-bit data acquisition with software controlled input/output gains, easy operation with on-line help, 1/l-octave to 1/12-octave band smoothing of measured frequency responses. The Liberty Audiosuite uses a versatile and powerful, yet inexpensive, DSPbased Personal Sound Architecture soundcard designed by Analog Devices and Echo Speech Corporation based around the ADSP2115 DSP processor. These boards include the orchid SoundWave 32 and GameWave 32 Plus, the Cardinal Digital Sound Pro 16, the Wearnes Beethoven, the Paradise DSP16, and the Echo soundcard. These boards generally also provide standard compatible multimedia sound and synthesis functions. A testing microphone needs to be purchased separately. The IMP microphone (plans available for builders) or the Mitey Mike could be used.


Name: LMS (Loudspeaker Measurement System)

Computer : MS-DOS .

Distributor: LinearX Systems inc

Agent: ME Technologies, Munro Associates, and many others.

Programmer: Chris Strahm

Price: US$ 1500

Description: The LMS features a programmable sine wave oscillator, dual tracking filters with LP/HP/BP/BR modes, and a high-speed gating system for quasi-anechoic measurements. Includes a calibrated condenser microphone referenced to B&K microphone. Electrical and acoustical tests include: SPL response, gated SPL curves, rub/buzz test, impedance response, Nyquist plots, polar plots, and inverse FFT. System utilities are provided for scaling, smoothing, subtracting, dividing, and PASS/FAIL curve comparisons. The Hilbert Transform is used to calculate an approximation to the phase curve. A macro programming capability is included for automatic test operation. Measurement files can be exported for use in loudspeaker CAD programs such as CALSOD and LEAP. A detuo is available by anonymous ftp, and there is also a Web site (see address details listed elsewhere).


Name: MLSSA 9. 0

Computer: MS-DOS

Distributor: DRA Laboratories

Agent: Harmonic Design GmbH, Munro Associates, and many others.

Price: US$3500 (hardware and software)

US$500 (MLSSA SPO Speaker Parameter option)

Description: MLSSA pioneered the maximumlength sequence (MLS) method of system analysis, which has significant benefits over simple impulse response measurement techniques. It has become a popular tool used by loudspeaker system designers and acousticians. It is an 8-bit PC card, with a 12-bit A/D converter is used, and the maximum sampling rate is 160kHz. Four sequence lengths are provided in hardware: 4K, 16K, 32K and 64K. MLSSA can measure a long impulse and store it to disk for later analvsis. Measurements over a lkHz bandwidth can be performed with 0.06Hz resolution, or 1Hz resolution over a 20kHz bandwidth. MLSSA can perform many mathematical operations on both time and frequency domain data files including average, add, subtract, multiply, divide, smoothing, convolution, correlation, and the inverse FFT. MLSSA also computes reverberation time and other acoustical parameters in IEC-standard octave bands, as well as energy-time curves (ETCs), absolute SPL and noise-criteria (NC) readings, speech transmission index (STI), ISO 3382 acoustical parameters, lateral energy fraction. MLSSA can act as an inductance and capacitance meter using impedance nieasurements (unaffected by the test lead series resistance). MLSSA can compute the minimum-phase and excess phase response from measured frequency response data, including the excess group delay which makes it easier to check the minimumphase behaviour of speakers. An Adaptive Window measurement technique is provided to mimic human hearing when performing room response measuretaents so that they look more like they sound. An integrated macro processor is provided, allowing complex sequences of commands to be recorded and played back. Measurement files can be exported for use in loudspeaker CAD programs such as CALSOD, LEAP, and XOPT.Frequency domain data can be exported and imported in linear format or logarithmic format for reduced file size. An additional software module (Speaker Parameter option or SPO) al lows measurement of Thiele-Smal I and electro-mechanical driver parameters us ing added-mass and closed-box methods. A rub detection measurement technique is also provided, and automated quality control acceptance limits and pass/fail functions are supported.



Name: System Two

Computer: Microsoft Windows 3.11 and Windows 95

Distributor: Audio Precision inc

IRT Electronics Pty Ltd (Australia)

Price: SYS-2022 two-channel analog test set.

SYS-2222 analog domain test set plus DSP modules.

US$18000 SYS-2322 dual domain test set plus digital I/0.

SYS-2300 same as SYS-2322 but no analog domain capability. `

Description: The System Two is designed for use from an external computer, including small notebook computers. It includes true Dual Domain architecture, allowing measurements in both the analog and digital domains. Analog hardware gen'erator and analog hardware analyzer for analog domain devices is separate and independent from DSP modules which stimulate and analyze digital domain devices. Analog generator: distortion120dB, flatness 0.01dB. Analog analyzer: res idual noise -117, 7dBu, flatness 0.01dB, residual THD+N -110dB (0. 0003%), and FFT analysis following analog notch filter down to -140dB. Digital domain: signals are pure to -135dBFS, THD+N residuals below -120dB, and FFT dynamic range and accuracy extend to -140dBFS. System Two's user interface is the APWIN software (Windows 3. 11 and Windows 95 versions), and includes extensive on-line help. APWIN features include: keystroke-learned test procedures, easy creation of acceptance limits, sweeping with automatically computed steps or from tables, and a data settling algorithm which maximizes sweep speeds while still providing stable, repeatable data. FFT analysis via synchronous multi-tone techniques operates with no time domain windowing function before the FFT, allowing for the first time proper noise measurements of compressors, processors, and noise gates. Signals generated in both analog and digital domains: sinewaves, squarewaves, SMPTE/DIN, CCIF, and DIM/TIM IMD signals. Additional analog-generated signals include: random and pseudorandom white and pink noise, bandpassed noise. Multitone signals are generated in the digital domain and available at both digital and analog outputs. Predefined and user defined equalization curves can be applied to analog or digital generator outputs during a sweep, or a tueasured parameter may be equalized. Complete test setups and measurement results can be stored to disk for later retrieval


Name: TEF System 20 and Sound Lab Software

C0mputer: MS-DOS and Macintosh

Distributor: TEF Products

Price: US$5000 (dependent on hardware and software configuration)

Description: The TEF system is a computer-based analyzer designed to make quick, accurate measurements of room acoustics, sound systems, and audio components. TFF measuremonts are then used to help solve room acoustics problems, deiermine installation parameters for large sound systems, or determine the performance of individual system components. The term TFF is derived from time, energy, frequency. if TFF functions are based on Time Delay Spectrometry, a measurement method developed by the late Dr. Richard C. Heyser. Measurement capabilities include: 3-D waterfall plots, production testing, frequency response, phase response and group delay, polar response, frequency time curves, octave noise measurements, energy time curve (ETC), Nyquist display, SPL meter, oscilloscope, single channel FFT with up to 512k points, ALcons, RASTI, MLS measurements with 24kHz bandwidth, data sample lengths 255-512k points, alternate sequence seeds, display modes include overlay difference, and % octave smoothing, file import and export facilities in a variety of formats. A seven-disk demo software set provides a comprehensive review of all seven modules of the Sound Lab software.