CLIO ELECTRICAL & ACOUSTICAL TESTS User's Manual Version 4.
INPUT A INPUT B OUTPUT A OUTPUT B The CLIO PC board
© Copyright 1991–99 by AUDIOMATICA SRL All Rights Reserved Edition 4.06, September 1999 IBM is a registered trademark of International Business Machines Corporation. Windows is a registered trademark of Microsoft Corporation.
CONTENTS 1 INTRODUCTION........................................................................................ 9 1.1 GENERAL CONDITIONS AND WARRANTY ............................................................................ 9 1.2 THE HARDWARE OF CLIO .................................................................................................... 11 1.3 THREE SOFTWARE VERSIONS ........................................................................................... 11 1.
DISK MENU AND FILES MANAGEMENT .............................................. 39 6.1 INTRODUCTION ..................................................................................................................... 39 6.2 DATA FILES ORGANISATION ................................................................................................. 39 6.3 LOADING FILES ...................................................................................................................... 39 6.4 SAVING FILES .....
10 MLS MENU ............................................................................................ 63 10.1 INTRODUCTION ................................................................................................................... 63 10.2 DESCRIPTION OF MLS THEORY ....................................................................................... 63 10.3 MLS ANALYSIS CONTROL PANEL ...................................................................................... 65 10.3.
13.2 EXPORT ............................................................................................................................. 107 13.2.1 FFT .............................................................................................................................. 107 13.2.2 MLS ............................................................................................................................. 108 13.2.3 SINUSOIDAL FREQUENCY RESPONSE AND IMPEDANCE ....................................
1 INTRODUCTION This User's Manual explains the CLIO system hardware and software. All software versions - Standard, Lite and QC - are covered; we remind you that the Standard and QC software are hardware protected and work in demo mode if the proper PC board (the one with the correct serial number) is not installed or found . If the software does not recognize the correct serial number works in demo mode! The CLIO software is year 2000 compliant. 1.
WARNINGS AND LIMITATIONS OF LIABILITY Audiomatica will not assume liability for damage or injury due to user servicing or misuse of our product. Audiomatica will not extend warranty coverage for damage of the CLIO system caused by misuse or physical damage. Audiomatica will not assume liability for the recovery of lost programs or data. The user must assume responsibility for the quality, performance and the fitness of Audiomatica software and hardware for use in professional production activities.
1.
n Input signal autorange for optimum signal to noise ratio. n Selectable analysis window n Manual or continuous programmable time average n Loop function with continuous measurement refresh n Mathematical operations on data in memory n Automatic merge function between near and far field n Selectable smoothing factor (from 1/2 to 1/12 of octave) 1.4.
n Two channels measurement and display (time and frequency) n Internal trigger with programmable delay (time and frequency) n Real-time THD calculator n FFT up to 4096 points n Transfer function between input channels Modulus, real and imaginary parts display n Linear or logarithmic frequency axis n Linear or dB amplitude scale n Alltone signals for real-time transfer function n Multitone signals generation With FFT it is possible to easily execute bursted distortion measurements delivering, for a definable
1.5 THE QC (QUALITY CONTROL) MEASUREMENT MENU PLUG-IN The QC software represents Audiomatica’s “on-field developed” solution for any production facility; it is a plug-in software that enhances CLIO 4 giving the possibility of no-compromise testing of production lines.
2 THE CLIO SYSTEM Depending on the hardware options that have been purchased, the CLIO system consists of the following components: – The HR-2000 PC board – The MIC-01 or MIC-02 (also Lite) microphones – The PRE-01 microphone preamplifier – The ClioQC Amplifier & Switch Box In the next few pages we will describe each component and give its respective technical specifications. NOTE: Audiomatica reserves the right to modify the following specifications without notice. 2.
ANALYZER Type: Input range: Input impedance: Phantom: Two channel 16-bit sigma-delta A/D converter +30 to –40 dBV 64 kohm 8.2 V (5.6 kohm mic input impedance) MISCELLANEOUS Sampling frequencies: Card type: Card connections: 16 51.2 kHz, 25.6 kHz, 12.8 kHz, 6.4 kHz, 3.2 kHz and 1.
2.2 THE MIC-01 MICROPHONE The MIC-01 microphone is an electret measuring microphone that is particularly well suited to be used in conjunction with the other components of the CLIO system. It is furnished with its own stand adaptor and a calibration chart, all fitted in an elegant case. Its long and thin shape renders it ideal for anechoic measurements. Because its frequency response is very flat over the entire audio band, no particular correction is needed for professional-quality measurements. 2.2.
2.3 THE PRE-01 MICROPHONE PREAMPLIFIER The microphone preamplifier PRE-01 has been designed to match Audiomatica’s microphones MIC01 and MIC-02. It is particularly useful when the microphone has to be operated far from the analyzer or when weighted measurements are needed. PRE-01 powers the microphone connected to its input with an 8.2V phantom supply and adds a selectable weighting filter (A or B or C); also available there is a 20 dB gain stage.
2.4 THE CLIOQC AMPLIFIER & SWITCH BOX The CLIOQC amplifier and switch box is of invaluable help when configuring an automatic or manual quality control setup and even in everyday laboratory use.
PC control Input 1 Input 2 To CLIO Input 8 From CLIO Speaker 10 dB I Sense Internal connections for impedance measurements 2.4.1 TECHNICAL SPECIFICATIONS Inputs: Functions: Output power: THD (1 kHz): Dimensions (cm): Weight: AC: 20 Two (Model 2) or eight (Model 3) line/microphone inputs with selectable phantom power supply (8.2V) TTL controlled internal switches for impedance measurements 10W with current sensing 0.004 % 23x9x23 2.
3 INSTALLATION OF CLIO NOTE: PLEASE REFER TO CHAPTER 4 FOR POTENTIAL PROBLEMS REGARDING THE COMPATIBILITY OF THE CLIO SYSTEM WITH YOUR PC (EITHER HARDWARE OR SOFTWARE). 3.
5) Close the cabinet. 6) Reconnect the mains cable and switch the computer on. At this point the CLIO board hardware installation is finished. To proceed further, you need an RCA pin-to-pin cable (one of those used in a stereo system) to connect the CLIO channel A input and channel A output; we strongly suggest you to carefully follow paragraph 3.4 in order to verify the correct behavior of your CLIO system.
3.4 RUNNING CLIO FOR THE FIRST TIME If you have completed the preceding installation procedure, you are ready to run CLIO! The steps hereafter described will guide you through a complete verification of the system performance and operation. FIGURE 3.2 To run the software just type CLIO (be sure to start from within the CLIO system directory) and . You should see CLIO’s main window (Fig. 3.2). After having answered the initial prompt you are ready to make your first measurement.
you can inspect the amplitude of each single frequency bin, if it is positioned as in figure the marker will read the level at 1 kHz of -2.2 dBV. Press Esc to exit the FFT control panel and go back to CLIO’s main menu. FIGURE 3.7 FIGURE 3.8 FIGURE 3.9 FIGURE 3.10 We will now undertake the system calibration procedure: press “D” to enter the Disk menu and “C” to start the system calibration (Fig. 3.
To start working with CLIO you may want to familiarize yourself with the user interface and the many hot keys. Read carefully chapters “5-Clio’s User Interface”, “6-Disk Menu and Files management” and “7-Configuring and Calibrating Clio” after this chapter before proceeding further. 3.5 CLIO CONNECTIONS The CLIO board has four RCA plugs that are used to connect it with the outside world (Fig. 3.12). The lower ones, J1 and J2, are the two outputs, while J3 and J4 are the inputs.
measuring point and ground. Use Shift-F1 to recall the global/local settings dialog box and select the input channel desired; refer to chapter 7 for any further detail about it. WARNING: Both CLIO inputs and outputs are referred to a common measuring ground.
INPUT A PC-IBM CLIO INPUT B OUTPUT A OUTPUT B FIGURE 3.14 – Connection for calibration INPUT (A OR B) PC-IBM CLIO OUTPUT (A OR B) MIC-01 OR 02 AMPLI BLA CK RED RED BLA CK FIGURE 3.
INPUT A PC-IBM CLIO INPUT B ZX OUTPUT A OUTPUT B FIGURE 3.16a – Impedance measurements in "Internal Mode" INPUT A PC-IBM CLIO INPUT B RS OUTPUT A OUTPUT B ZX BLA CK AMPLI RED FIGURE 3.16b – Impedance measurements with an external sensing resistor Rs in "Constant Current Mode" INPUT A PC-IBM CLIO INPUT B ZX OUTPUT A OUTPUT B RS BLA CK AMPLI RED FIGURE 3.16c – Impedance measurements with an external sensing resistor Rs in "Constant Voltage Mode" FIGURE 3.
INPUT A INPUT B CLIO OUTPUT A PC-IBM OUTPUT B LPT PORT CLIOQC AMPLIFIER&SWITCHBOX I SENSE BLACK RED 10 dB FROM CLIO TO CLIO INPUT 1 INPUT 2 INPUT 8 FIGURE 3.17 – ClioQC Ampli&SwitchBox with internal connection for response measurements INPUT A INPUT B CLIO OUTPUT A PC-IBM OUTPUT B LPT PORT CLIOQC AMPLIFIER&SWITCHBOX I SENSE BLACK RED 10 dB FROM CLIO TO CLIO INPUT 1 INPUT 2 INPUT 8 FIGURE 3.
Chapter 3 – Installation
4 PC COMPATIBILITY 4.1 HARDWARE COMPATIBILITY CLIO’s hardware makes intensive use of the resources of the computer in which it is installed. Its functionality is based on two DMA (Direct Memory Access) 8-bit channels that are present on the PC main board with 80286 and higher processors. One DMA channel is used for generation and the other for acquisition. Four I/O addresses are also used, and these can be specified to start at HEX 300 or HEX 310, depending on board and software configurations.
Chapter 4 – PC compatibility
5 CLIO’S USER INTERFACE 5.1 GENERAL INFORMATION CLIO’s user interface has been created by embodying many modern concepts relating to the design of graphical user interfaces for programs running on personal computers. Many of these ideas have been implemented in products such as the Microsoft Windows graphical environment, which has enjoyed a high degree of acceptance by computer users.
5.3 CONTROL PANELS Fig. 5.3 shows a typical control panel (obtained after choosing the Analyze option from the MLS menu). In general, the screen will be divided into three physically and functionally distinct areas. title bar buttons measurement screen cursor title bar status line function buttons FIGURE 5.
remains active when it is pressed, and changes colour to confirm that a particular operational mode has been selected. To deactivate such buttons it necessary to press them a second time. THE STATUS LINE This is located between the function buttons and the end of the graphics window, and it is used to present useful messages to the user that help to enhance the understanding of the measurement.
5.4 HOT KEYS These are the keyboard keys that are always active from within any menu or control panel. They are a quick and convenient way to execute many of the most commonly used operations. They are not visible and therefore may not be selected with the mouse. After frequent use, these keys should become easy to remember. Let us now take a look at them in detail: ESC Exits the current control panel or dialog box. Alt-P Prints the executed measurements from within any control panel.
5.5 CLIO HELP ON LINE Pressing the Ctrl-F1 Hot Key or clicking on the icon you enter the CLIO Help On Line (Fig. 5.4). FIGURE 5.4 – CLIO Help On Line (from MLS control panel) This dialog box gives help relative to the control panel from which it has been recalled; to navigate it is possible to use the ↑, ↓, PageUp, PageDown, Home and End keys.
Chapter 5 – CLIO’s User Interface
6 DISK MENU AND FILES MANAGEMENT 6.1 INTRODUCTION As you might expect from its title, this chapter deals with the functions that result in read or write access to and from the hard disk. Setup, Calibration and Exit functions, although not logically tied to disk operations, are also present in this menu as they are of such common use. Before we begin examining each item on this menu, we strongly recommend that you read through the chapter 5 describing the use of CLIO’s “hot keys”.
File dialog box appears as in Fig. 6.1 (as an example from the MLS Analyze control panel). This dialog box displays a list of files all of which have the same extension used in that prticular control panel. As a refernece the file name extensions that CLIO uses are: Fft: measurement files obtained through the Fft menu. Mls: measurement files obtained through the MLS Analyze menu. Wtf: measurement files obtained through the Mls Waterfall menu.
operation. The directory in which the file is saved is the current active directory (see the Chdir and Mkdir menu commands for further details). Aside from the measurement itself, additional relevant information will also be saved. This includes a comment that can be added by means of the About button, as well as several settings related to the measurement. 6.5 Mkdir This command creates new work subdirectories that will be put under the DATA directory.
Chapter 6 – Disk Menu and files management
7 CONFIGURING AND CALIBRATING CLIO 7.1 INTRODUCTION This chapter explains how to correctly configure the CLIO system software in order to obtain the best results when performing electrical and acoustical measurements. Section 7.2 will explain how to configure CLIO at startup. Section 7.3 will deal with some software configuration issues related to the CLIO board that will affect all measurements. Section 7.4 will cover various aspects of configuration that are related to the PC platform (e.g.
7.3 MEASUREMENT SETTINGS The measurement specific configuration items can be input from within some control panels or even from the main window. There are Local Measurement Settings that are private to each type of measurement and are loaded every time one enters a control panel. There are also the Global Measurement Settings that are the default condition when the program is run for the first time, and these settings are subsequently saved in the CLIO.STP file (see section 7.4).
– MLS – Scope NOTE: The lower the sampling frequency that you choose, the slower will become some of the measurements. This fact is readily understood if one considers the theory behind the sampling process. For example, if executed using a 3200 Hz sampling rate, the MLS measurement will take about 16 times the length of time it takes if executed at 51200 Hz (in fact the generator needs exactly 16 times the time to play the MLS of the same length). 7.3.
7.4 THE DISK Setup CHOICE After choosing Setup from within the Disk command presented on the menu bar, one enters the Setup dialog box, which is shown in Fig.7.2. It is possible to configure your printer, on-screen colours, as well as CLIO’s I/O address from the various parameters displayed in this dialog box. FIGURE 7.2 – The Disk Setup dialog box 7.4.
7.4.4 EXTERNAL HARDWARE CONTROL The CLIO software release 4 and QC is able to control external hardware by means of the TTL signals generated with the parallel printer port of the PC. It is possible to activate the selected printer port for external control or disable it. If TTLCONTROL is left to OFF no output control is performed (also the SHIFT-F4 hot key is disabled).
7.6 CALIBRATING CLIO To calibrate CLIO it is necessary to connect the A output directly to the A input. INPUT A PC-IBM CLIO INPUT B OUTPUT A OUTPUT B FIGURE 7.6 – Connection for calibration NOTE: Always wait for the computer system and the installed CLIO board to reach a stable temperature. Never try to calibrate or verify the accuracy during the first few minutes that the computer has been on. You should wait at least fifteen minutes before trying any calibration operation. 7.6.
The calibration procedure is completely automatic and several progress indicators will accompany all the executed measurements. After about some minutes (depending on the computer speed) calibration process will be concluded and the program will once again enable the user to select commands. The calibrations will be saved (inside the CLIO directory) in six different files with the names “MLS1.CAL”, “MLS2.CAL”, “MLS3.CAL”, “SIN.CAL”, “LEV.CAL” and “RTA.CAL”.
Always keep in mind that a calibration has to be made: – when first installing CLIO – every time the software is reinstalled – every time the program requests it (by means of an appropriate message) – when, in the user’s judgement, the measurement conditions have changed. In order to determine, at any given time, if it is necessary to calibrate CLIO, one must first let the system warm up.
8 TOOLS MENU 8.1 GENERATOR & LEVEL METER CONTROL PANEL FIGURE 8.1 – The Generator & Level Meter control panel 8.1.1 INTRODUCTION The Generator & Level Meter control panel shown in Fig. 8.1 is of fundamental importance while using CLIO.
PRESSURE MODE In this measuring mode the reading is selected to be in dB SPL (sound pressure level). Readings taken in dB SPL are relative to a pressure of 20 µPa. While in Pressure mode, the four buttons labelled Vrms, dBRel, dBV and dBm are disabled. 8.1.3 SIGNAL GENERATOR The CLIO board has a built-in two-channel programmable signal generator. Although the two channels could be separately driven, CLIO software Release 4.
2Sin Starts the generation of a double tone. Two frequency input field control the desired frequencies. Amplitude of each sinusoid is controlled with the level 1 and level 2 in percentage of full scale. Obviously the sum of the two cannot exceed 100%; it can be less but in this way you loose part of the 16 bits resolution. White Starts the generation of pseudo-random white-noise signal. This signal can also be selected from the displayed list of available signal files (WHITE.SIG).
In+ Increments the input sensitivity in 10 dB steps; the same effect can be obtained by pressing the F10 key. In- Decrements the input sensitivity in 10 dB steps; the same effect can be obtained by pressing the F9 key. A Selects channel A to be used as input. Alt-1 hot key does the same job. B Selects channel B to be used as input. Alt-2 hot key does the same job. A-B Selects both channels to be used as input in a balanced differential configuration. Alt-3 hot key does the same job.
8.3 SCOPE CONTROL PANEL 8.3.1 INTRODUCTION FIGURE 8.3 – The Oscilloscope control panel The Oscilloscope control panel (Fig. 8.3) turns the CLIO board into a powerful low-frequency dual channel oscilloscope. It is possible to view the input signal on a rapidly updating display, capture it, and save it to a file. The signal can be triggered (with programmable delay) by the internal generator, thus permitting the analysis of transient signals such as sinusoidal bursts.
TRIG LEVEL UP AND DOWN Select a trigger level (as a percentage of the scale). A and B buttons select the channel for the trigger in dual mode. The right channel is automatically selected in single channel mode. NOTE: the above eigth buttons are accessible from the keyboard with the TAB, SHIFT-TAB and SPACE keys. When a button is active, it is highlighted by a thicker border. Use the TAB key to move forward and select a button. Use the SHIFT-TAB keys to move backwards and select a button.
9 FFT MENU NOT available in Lite version! 9.1 INTRODUCTION By selecting the FFT command from the main menu bar, it is possible to carry out Fourier analysis of the input signal to determine its frequency content using the Fast Fourier Transform (FFT).
of three): this lets the user select the more appropriate sampling and to reach the lower limit of 1600 Hz sampling with a maximum of 0.39 Hz frequency resolution. FIGURE 9.2 – The FFT Locals dialog box Please note that, differently from all the others control panels, the choice of the input acquisition channel is not made in this dialog box but in the FFT measurement settings one. When you recall it, as seen in figure 9.
Freq.Axis Selects linear or logarithmic scale for the frequency axis. MAG Scale Selects linear or decibel scale for the Y-axis when Magnitude display is selected. NOTE: These settings and the graph control ones (see next) are saved with the measurement data in the FFT file on disk; when you recall a previously saved file its settings will reset the FFT control panel. 9.2.2 GRAPH CONTROL These settings define the conditions under which the FFT measurement is displayed.
9.2.3 FUNCTION BUTTONS Start Starts a new FFT measurement. The display will continuously refresh but if you are in Average mode the measurement will end after the pre-defined number of averages has been reached, unless you manually stop the measurement process. NOTE: The input sensitivity reflects the value set within the Generator&LevelMeter (and controllable with the F9 and F10 keys) control panel; if the input AutoRange (see 8.1.5) is selected also the FFT will autorange.
Window Activates the application of a time weighting window on the input signal. The window type can be selected from the FFT Settings dialog box. IntTrig Causes CLIO to enter the Internal Trigger mode. The acquisition is then triggered by the internally generated signal and starts after a delay time that can be input in the Scope Trigger Settings dialog box (see 8.3.2).
Chapter 9 – FFT Menu
10 MLS MENU 10.1 INTRODUCTION In this measurement mode, CLIO is able to carry out analysis of linear systems based on the properties of signals known as Maximum Length Sequences (MLS). One of the many interesting results that one can achieve is the measurement of an anechoic sound pressure response of a loudspeaker. i.e.
shown in Fig. 10.1). On the other hand, the MLS signal is a deterministic and periodic signal with a repetition frequency equal to the inverse of its length (in our case 16383 samples, which corresponds to 320 milliseconds), and its characteristics will be known at any instant in time. These kinds of signals are therefore named pseudo-random noises. The main property of the MLS sequence is that its autocorrelation function is, aside from a negligible DC error, a perfect impulse.
10.3 MLS ANALYSIS CONTROL PANEL The MLS Analysis control panel (Fig. 10.3) is used when carrying out electrical and acoustical measurements using the MLS_14.SIG signal as a stimulus applied to the device under test. By using the controls that are available on the MLS Analysis control panel, it is possible to manage the acquisition of the measurement and the frequency domain display. From this panel one can enter the Impulse Response control panel.
the MLS_14.SIG file from the list. The software will automatically autorange the input signal thus optimizing dynamic range. Although the MLS measurement is extremely insensitive to noise, when performing a measurement it is still always a good rule to try and minimise all possible extraneous noises. To familiarise yourself with these kinds of problems, we suggest that you deliberately cause some noise during a measurement to evaluate its effects on the final result.
FIGURE 10.4 – Typical amplitude and phase response curve this button the Mathematical Tools dialog box shown in Fig. 10.5 will appear on your screen. Four fundamental mathematical operations are present: Add (addition), Sub (subtraction), Mul (multiplication), Div (division). Several extra options are also present: Shift, Delay, Merge and Inside.
bibliography references for further information related to the application of this technique. If the “Delay” operation has been selected, a positive or negative time shift is applied to the measurement. This is extremely useful in correcting any large group delay that might arise, such as from acoustical measurements. If the “Merge” operation has been selected, two response, the one in memory and the one in the selected file, will be merged.
10.3.2 THE MLS SETTINGS DIALOG BOX Amp.Scale Modifies the range of the amplitude display. It is possible to select between five different scales: 1, 2, 5, 10, 20 dB/division. The same result is obtained by pressing the Page Up and Page Down keys from within the MLS control panel. Smoothing Activates a frequency smoothing of the active curve. FIGURE 10.6 – Example of one-third-octave smoothing This smoothing effect will allow for a better appreciation of the general features of the response curve. In Fig.
– 20 to 20000 Hz – 200 to 20000 Hz – 2000 to 20000 Hz sampling frequency = 12800 – 5 to 5000 Hz – 50 to 5000 Hz – 500 to 5000 Hz sampling frequency = 3200 – 1.25 to 1250 Hz – 12.5 to 1250 Hz – 125 to 1250 Hz The same result is obtained by pressing the Home key from within the MLS control panel. Phase Used to select how phase response is obtained. Normal calculates and displays the phase curve starting from the selected time domain data.
between each measure; it is useful, for example, in averaging different microphone positions. 10.4 IMPULSE RESPONSE CONTROL PANEL The impulse response control FIGURE 10.7 – The Impulse Response control panel panel shows the time behaviour of the system impulse response (Fig. 10.7). A complete understanding of all the possibilities that this panel offers is a fundamental necessity in order that the measurement results are correct and satisfying.
FIGURE 10.8 - Effect of group delay on phase response FIGURE 10.9 – Phase response with group delay effect removed the sound wave emitted by the loudspeaker before its arrival at the microphone, the phase response will of course show a rapid linear variation with increasing frequency. This is the so called “sawtooth” or “wrap-around” effect that greatly reduces the legibility of the measured phase response.
→ and ← Moves the cursor one single sample (20 µs) in the appropriate direction. >> and << Moves the cursor 10 ms to the right or left, and this action can be performed by pressing the PgUp and PgDown keys. ↑ and ↓ Modifies the curve’s amplification factor in the appropriate direction. Start and double click left mouse button Selects the starting point of the analysis window. This action is accomplished by pressing “S” or clicking the button using the mouse.
End By pressing this key, the cursor will be brought within the last 10 ms (310 to 320 ms) of the temporal response. FIGURE 10.10 – The ETC control panel ← Ctrl→ → and Ctrl← Moves the cursor twenty time samples in the according time direction. 10.5 ETC CONTROL PANEL The ETC control panel is shown in Fig. 10.10, and it is used to analyse the energy-time curve.
algorithm and is suitable for longer analysis periods. Two typical short and long term ETC curves are shown in Fig. 10.11. 10.5.1 FUNCTION BUTTONS → and ← Moves the cursor one pixel in the appropriate direction (the actual time step depends on the pre-defined length).
>> and << Moves the cursor 20 pixels in the appropriate direction (the actual time step version! depends on NOT available in Lite the pre-defined length). This action can also be accomplished by pressing “Ctrl-RightArrow” and “Ctrl-Left-Arrow”, or by clicking the mouse on the corresponding buttons. Go Used to start a new measurement while remaining within the ETC control panel. FIGURE 10.
particular, for short term decay times (up to 10 ms) the representation is made on a 200 Hz to 20 kHz scale, while for longer analysis times a 20 Hz to 20 kHz scale will be used. NOTE: The program will not load the Waterfall control panel unless it finds a correct calibration file. Refer to the MLS Analyze Calibration chapter for all necessary information on this subject and on how to correctly calibrate this measurement.
interested in evaluating the quality of the coarse settings, or in determining settings that will provide an optimal display of information. Fig. 10.13 shows a comparison of the same analysis carried out with two different numbers of spectra. About Used to input, modify, or display text comments corresponding to the present measurement. Go Used to start the calculation of the cumulative spectral decay graph of for the selected active portion of the MLS curve.
The device under test is an anonymous commercial two-way loudspeaker system. We will begin by describing CLIO’s connections to the external world. As shown in Fig. 10.14, CLIO’s output A needs to be connected to the input of a power amplifier. An integrated amplifier can also be used, but the major imprecision that such a device may induce can be correlated to a correct attenuation versus frequency related to the various positions of its volume control.
FIGURE 10.16 – Measured response with and without first reflection therefore expect to have to sacrifice the possibility of being able to measure the lowest frequencies. Now let us study why this is so. Sound reflections arrive at the microphone after a time that is proportional to the distance from the microphone of the object that generated them. Therefore, in order to obtain an anechoic measurement, one must define a temporal window that excludes all undesired reflections.
is shown in Fig. 10.15, where some sound absorbing material has been placed on the floor to help reduce the intensity of the reflection from this surface. Fig. 10.16 shows two measurements where a temporal window has been used. One measurement includes the first sound reflection while the other excludes it. It is clear that a smoother response curve is obtained when the first reflection is omitted from the analysis. 10.7.
At this point enter “I” to eliminate the sound of the noise and Esc to close the generator and go back to the MLS Analysis control panel. Now we are ready for a real measurement! Press “G”. Within a few seconds we will have plotted the loudspeaker’s frequency response, an example of which is shown in Fig. 10.17. If no temporal window has been defined the response will appear irregular as in Fig. 10.17 due to the fact that in this case the response of the room and its reflections has also been analyzed.
it to disk. You should enter the Waterfall control panel by pressing “M” and “W” from CLIO’s main menu bar on the main screen. Before beginning the required calculation procedures, the results of an MLS measurement must have been loaded into memory (this is the reason why the Go button is not activated, should this not be the case). Press “M” to activate the MLS Analysis control panel directly from the Waterfall one, then press F3 to load the previously mentioned measurement.
Chapter 10 – MLS Menu
11 SINUSOIDAL MENU 11.1 INTRODUCTION All sinusoidal measurements that CLIO is capable of are described in this chapter. The options under the Sinusoidal menu command are the following: Frequency Response, Impedance, Parameters, Distortion, Polar and Calibration. These will now be described. 11.2 FREQUENCY RESPONSE This option is used to measure sinusoidal steady-state frequency responses. Fig. 11.1 shows the frequency response control panel. FIGURE 11.1 – The Frequency Response control panel 11.2.
(!) Burst response of D.U.T. has to be taken into account in selecting measurement speed; if in doubt, use the “Slow” one. In the Gate group the parameters for gating measurements can be defined. The most frequent application of this technique is quasi-anechoic frequency response of Loudspeakers. Basically you define an acquisition delay that takes account of the time of fly of the sound and a “meter on” time that should be short enough to exclude reflections.
NOTE: due to the overall bandwidth of the analyzer the second harmonic is limited to 12 kHz while the third harmonic is limited to 8 kHz. NOTE: the GenEq, Ref, Phase and Over function buttons are disabled when THD is active. NOTE: THD and Gate can be activated at the same time. However it should be pointed out that for meaningful distortion data the gate parameters are very critical. As a starting point the delay time should be increased slightly to prevent settling time of the speaker to affect distortion.
NOTE: When you activate this option, the Over option will be deactivated and all overlaid curves will be lost. It will be subsequently possible to recall the Over function to overlay more than one curve in the Ref mode. The same thing will happen when, by pressing the Ref button again, one returns to the normal mode.
If the “Inside” operation has been selected, the program will process a measurement that has been executed with the microphone placed inside the box so as to make it equal to one that has been executed in the open air. Please note that the level that is presented is rather arbitrary, and its interpretation is determined by experience of use.
11.3 IMPEDANCE This option serves to obtain impedance measurements taken under sinusoidal steady-state conditions. The modulus range in which the system furnishes reliable results in Internal Mode (see below) goes from 1 to 400 ohms. Once this option is chosen the Impedance Analysis control panel screen shown in Fig. 11.5 will be displayed. FIGURE 11.5 – The Impedance Analysis control panel 11.3.
Mode Allows to define four possible ways of measuring impedance. These are Internal, Constant I, Constant V and I Sense. The last one is feasible only if you are using a CLIOQC Model 2 or Model 3 amplifier (see later). Refer to figure 11.6 (a, b, c) for the right connections which are different in each case. Internal Mode, which does not require external amplifier, allows to measure impedance relaying on CLIO’s output impedance which is 100 ohm. CLIO’s output level is set during the measure to 0dB.
choice. It should be pointed out here that CLIO measures levels in both sensing points as complex values, that is real and imaginary part; therefore accuracy in case of linear devices is not affected by the ratio of sensing resistor to measured impedance as it would be with an RMS voltmeter. MEASURING IMPEDANCE WITH THE CLIOQC AMPLIFIER&SWITCHBOX If you use this unit the Impedance Mode setting interact both with the unit's own custom control panel (see also 7.4.4) and the relative connections with CLIO.
INPUT A INPUT B CLIO OUTPUT A PC-IBM OUTPUT B LPT PORT CLIOQC AMPLIFIER&SWITCHBOX I SENSE BLACK Zx 10 dB FROM CLIO RED TO CLIO INPUT 1 INPUT 2 INPUT 8 FIGURE 11.6e – Impedance measurements with the CLIOQC amplifier in "I Sense Mode" Phase The phase curve will be activated and it will be plotted on the display. The “Over” button can be useful when you want to simultaneously display both the modulus and the phase curves.
11.4 SPEAKER PARAMETERS This option is used to obtain the mechanical and electrical parameters of the loudspeaker. Having chosen this option, the control panel screen shown in Fig. 11.7 will be displayed. Before moving on to the description of each option, we would like to offer a few words of advice. The automatic determination of loudspeaker parameters may induce the user to believe that he may ignore the many considerations that lie behind this type of measurement.
At the end of this process a plot of the impedance curve will be shown, and a Minimum Square Error routine the will determine Fs and the various Q factors. Once this has been completed the display will update to show the measured parameters. Should there be any anomalies present on either the impedance curve or the estimated parameters, it would be imprudent to accept the values and to proceed any further with the estimation process.
happens pressing either Added Mass or Known Volume. Obviously in that case the file to select must have been done with one of the two methods. 11.4.2 ADVICE AND CAUTIONARY NOTES As was stated before, a loudspeaker’s parameters are deduced from an electrical measurement of impedance. Aside from the electrical parameters Re and Qes, there are acoustical and mechanical elements that act on the electrical part with greater or lesser contributions.
there are a number of possible drawbacks that can arise from the use of this method. They include the following: box losses due to air leaks; internal standing waves developed within the enclosure; structural resonance of the enclosure panels; the amount of air that moves together with the cone depends, among other things, on the shape of the box. All of these factors can work to reduce the accuracy of the parameter estimates unless care is taken when selecting a suitable enclosure.
NOT available in Lite version! 11.5 DISTORTION From within this menu it is possible to measure distortion Vs level or Power (Fig.11.8). Four Standards are available, THD, SMPTE, DIN and CCIF. FIGURE 11.8 – The Distortion control panel 11.5.1 FUNCTION BUTTONS THD Standard THD, Total Harmonic Distortion is Selected. Test Frequency is selected from within the Distortion Settings control panel as described below.
11.5.2 DISTORTION SETTINGS Several numeric input field define the needed parameters. THD Fr is for the frequency of THD measurements; it may range from 10Hz to 5kHz. CCIF Fr is for the frequency of CCIF measurements; the CCIF frequency typed in is in the center of the two. As an example typing a frequency of 15500Hz Clio will generate two tones at 15kHz and 16kHz. Admitted values are from 7kHz to 20kHz. START and STOP are for levels, in Volts or Watts, at which the measure should start and stop.
NOT available in Lite version! 11.6 POLAR This option is used to measure sound level at different angles from a sound source at a given frequency. Fig.11.9 shows the Polar control panel. Both manual and automatic rotation device are handled from Clio. As automatic rotation device the Outline model ET1 - ST1 automatic electronic turntable is controlled via LPT port.
11.6.2 OTHER FUNCTION BUTTONS Over Activates the overlay mode for plots. Two curves can be displayed, that is the one in memory and the previous one that appears with dashed line in a different colour. About Used to add, display, and modify the text of a comment used to describe the measurement. The comment will be saved along with the measurement, and the print routine will print it along with the measurement.
Chapter 11 – Sinusoidal Menu
12 RTA MENU 12.1 INTRODUCTION With this menu command it is possible to carry out one-third-octave analysis. The frequency range that is covered goes from the one-third of an octave centred on 20 Hz to the one centred on 20 kHz. The results of the measurement are plotted on the screen, and the plot is updated at a rate that is largely dependent on the speed of the PC. 12.
12.3 RTA CONTROL PANEL If the RTA menu is selected from the main menu bar, followed by the Analyze command, the control panel shown in Fig. 12.1 will be displayed if a calibration has already been carried out. The various buttons available on this control panel will now be described. FIGURE 12.1 – The RTA control panel dB Allows one to modify the range to be covered by the amplitude display. The two possible scales are 10 dB and 5 dB per division.
About Used to add, view, and modify a comment on the present measurement. This comment will be saved along with the measurement and will also be reloaded with it. The print routine will print this comment along with the measurement. Load Used to load on screen a reference curve that was obtained from an earlier measurement that had been saved on disk. Clear Clears the reference curve from the screen. 12.
12.5 IASCA SCORING NOT available in Lite version! This dialog box (fig. 12.2) calculates the International Auto Sound Challenge Association (IASCA) scoring for the SPL/RTA tests, as is reported on the Official Judging Rules. FIGURE 12.2 – The IASCA scoring dialog box (with 1993 rules) The score is calculated starting from the RTA and the LEQ measurements loaded in memory; it is necessary to perform at least one of the two measurements in order to obtain a calculation.
13 FILE EXPORT AND IMPORT 13.1 GENERAL INFORMATION With the use of the Shift-F2 hot key, which is active in almost all of CLIO’s control panels, CLIO exports measurements in an ASCII text file format, with .txt extension, that is useful in a great number of cases. The main purpose of this feature is the exchange of data with other programs, particularly simulation and modelling programs.
[FREQ] [CH A MAG dBV] 50.0 -75.77 100.0 -75.39 150.0 -75.72 200.0 -75.63 250.0 -77.14 ............... ............... 19850.0 -90.41 19900.0 -90.19 19950.0 -89.34 20000.0 -89.34 13.2.2 MLS Both Frequency and Time data can be exported from here. Frequency data are exported with ShiftF2 from the MLS Frequency Response control panel while Time data from within the Impulse response one. Frequency data are 540 lines of logarithmic spaced frequencies.
13.2.3 SINUSOIDAL FREQUENCY RESPONSE AND IMPEDANCE Data exported here depends on Measure Settings, not on the display ones, that is start and stop frequency and resolution. If THD button is active 2nd and 3rd harmonic value are exported. Freq dB Phase 10.0 -70.56 -28.9 10.6 -68.70 -33.0 11.2 -66.90 -37.8 11.9 -65.08 -42.0 12.6 -63.29 -46.7 13.3 -61.52 -51.4 14.1 -59.84 -56.1 15.0 -58.17 -60.7 15.8 -56.49 -65.5 16.8 -54.85 -70.2 .......................... .......................... 16788.0 -6.84 -98.6 17782.
17278.4 17782.9 18302.2 18836.6 19386.7 19952.8 94.99 95.30 93.81 91.79 90.92 91.24 86.4 177.2 -97.2 16.0 136.0 -112.5 -226.00 -226.00 -226.00 -226.00 -226.00 -226.00 -226.00 -226.00 -226.00 -226.00 -226.00 -226.00 Freq Ohm Phase 10.00 4.15 34.20 10.29 4.22 34.91 10.59 4.28 35.64 10.90 4.36 36.36 11.22 4.44 37.09 11.55 4.52 37.83 11.89 4.61 38.56 12.23 4.71 39.29 ........................... ........................... 18302.20 19.22 53.70 18836.63 19.56 53.92 19386.68 19.88 54.13 19952.78 20.24 54.
Cms 0.84 [mm/N] 13.2.6 SINUSOIDAL DISTORTION Lev [W] Dist [%] 0.37 0.27 0.40 0.30 0.44 0.32 0.49 0.34 0.53 0.36 ............... ............... 12.19 0.42 13.37 0.45 14.66 0.49 16.07 0.53 17.63 0.56 19.32 0.60 21.15 0.67 23.22 0.97 25.27 2.62 27.21 6.71 29.24 13.06 13.2.7 SINUSOIDAL POLAR Test Frequency 3000 Angle dBSpl 0 92.46 5 92.50 10 92.43 15 92.21 20 91.86 25 91.38 .......... .......... 330 90.29 335 90.91 340 91.41 345 91.80 350 92.10 355 92.
13.2.8 RTA Freq 20 25 31 40 50 63 80 100 125 160 200 250 315 400 500 630 800 1000 1250 1600 2000 2500 3150 4000 5000 6300 8000 10000 12500 16000 20000 112 dB 75.07 80.02 82.67 83.90 85.98 87.34 90.32 92.45 90.32 88.33 87.02 89.01 91.21 92.90 92.92 92.29 90.32 89.23 88.31 87.90 86.71 85.45 85.32 86.21 84.99 83.23 82.21 81.21 81.01 80.21 73.
13.3 IMPORT From the Sinusoidal Frequency Response control panel, with the hot-key Shift-F3, is possible to import measures saved as ASCII files in the same format Clio uses for export. This allows for example to import MLS exported measurements and compare them with Sinusoidal ones, to visualize hand edited responses, responses produced by other programs, as well as files used for the GenEq option. Once you have imported the file it is possible to save it as a Clio’s internal format .frs file.
Chapter 13 – File Export and Import
14 ACOUSTICS MENU NOT available in Lite version! 14.1 INTRODUCTION This menu will allow CLIO users to carry out measurements in the architectural and room acoustics field as well as in the noise control field. 14.2 REVERBERATION TIME ANALYSIS With the RT60 control panel CLIO is able to make the reverberation time (RT60) calculation based on a particular post-processing of the system impulse response acquired through an MLS-based measurement.
14.3 THE RT60 CONTROL PANEL Figure 14.2 shows the RT60 control panel. FIGURE 14.2 – The T60 control panel Besides the function buttons located under the measurement screen there are two more groups of buttons (the octave buttons and the limits buttons) that are located at the right of the measurement screen and that are useful during the interaction with this control panel. NOTE: When saving or loading files from disk, you must always remember that the file extension associated with this measurement is “.
FIGURE 14.3 – The T60 bar display Go This starts an RT60 measurement.
About Used to insert or display a text comment describing the present measurement. The comment will be saved with the measurement. 14.3.2 OCTAVE BUTTONS These button are normally disabled when first entering the RT60 control panel; once a measurement has been taken or a file has been loaded from disk they select the octave for which the decay curve is displayed and the reverberation time is calculated. 14.3.
14.4 LEQ ANALYSIS With the LEQ control panel CLIO is able to make the real-time Leq (equivalent sound level as defined in IEC-804 standard) calculations. In fig.14.4 you can see the Leq plotted versus the actual level of the signal (time history); Leq can be regarded as the level of a signal that, if held constant, would have the same energy content over the observation interval. FIGURE 14.4 – Time history and equivalent level Leq of a signal 14.4.
14.5 THE LEQ CONTROL PANEL In fig 14.5 we can see the LEQ control panel. FIGURE 14.5 – The Leq control panel The software displays, while the LEQ measurement is progressing, both the time history and the equivalent level of the signal (see fig 14.4).
NOTE: if not stopped before, the measurement is automatically ended when time reaches the Stop Time value. Sett Used to select the Integration and the Stop Time. The Integration can be selected between: -”Impulse” 31.25 ms averaging -”Fast” 125 ms averaging -”Slow” 1 s averaging The maximum allowable Stop Time is 23h 59m 59s. NOTE: Use the slowest possible integration as this directly reflects on the disk space needed to perform the measurement; the software creates the “DUMP.
Chapter 14 - Acoustics Menu
15 QUALITY CONTROL MENU Available ONLY in QC version! 15.1 INTRODUCTION The quality control menu adds to the CLIO system the possibility of no compromise quality control testing of production lines.
15.2 THE QUALITY CONTROL SOFTWARE OPERATION The QC software is a “file driven” event processor that, in series, performs a number of user-defined measurements to test the quality of a production line.
CLIO has the possibility of, in series, execute up to: - 40 different Level QC tests - 14 different FFT QC tests - 10 different MLS QC tests - 10 Polarity checks - 4 different Sinusoidal Impedance QC tests - 4 different Sweeps The tests may be executed presenting simple "go-nogo" masks as in Fig. 15.1 without any information, except the aforementioned ones, regarding the measurements executed.
15.2.1 HOW IT WORKS Let's now see an example of a fairly simple sequence of two QC tests: a FFT two tones distortion test and a MLS frequency response test.; refer to figures 15.3 and 15.4. A B C 126 FIGURE 15.
The definition of this QC test will be done within an ASCII file (the SETUP FILE) that we will describe later in this chapter. In Fig. 15.3 we see the normal flow of the QC tests sequence; we also suppose that the first test (FFT) will be passed good.
15.2.2 EXTERNAL TRIGGER The described QC tests sequence can be triggered (started and continued) by an external signal (see 15.6) and this is controlled by the MANUAL mode. The default operating mode is manual and the user has to press a key for starting the whole QC tests sequence; in the previous example we were operating in manual mode. Otherwise, when NOT in Manual mode, the QC control panel changes as in Fig. 15.
15.3 QC FILES As already underlined in the preceding section the QC software is a “file driven” event processor. The setup, reference and limits files are necessary to define and run a QC test; the report files and the autosaved measurement files are usually the output product of a QC session; the cyclic file is a particular setup file described later. 15.3.1 THE SETUP FILE The setup file is an ASCII file with the extension ".STP" where all information regarding a QC session are stored.
... ... MANUAL=0 NOTE: to write and save a setup file you have to use a external program like the DOS Edit, Windows Write or W95 Wordpad or any other word processor; please be sure to save the file in a plain ASCII format; no other control or formatting characters have to be present. Remember also that the required extension for these files is ".STP". The setup file syntax is fairly easy; you have several keywords (see later 15.
15.3.3 LIMITS FILES A limits file is an ASCII file with the extension ".LIM" containing the definition of the limits of the QC mask.
CYCLIC=TESTCYCL.STP REPETITION=100 In this case the file named "TESTCYCL.STP" is executed every one hundred QC tests. The cyclic file syntax is the same as a normal setup file. It is also possible to execute the cyclic setup file before the actual beginning of the QC session; in this case one has to use the following syntax: CYCLICFIRST=1 When the cyclic sequence is initiated the operator is prompted with the following dialog box: Pressing SpaceBar the cyclic sequence is initiated.
REPORT FILES These files are written by the software as documentation of the executed tests; their name is automatically generated starting from current date and QC session number; their extension is ".STA" and they reside in the \REPORT subdirectory under the current work directory; as an example the following report file would be named "20059702.STA" meaning QC session 2 in date 1997, May 20th.
15.4 DEFINITION OF A QC MEASUREMENT CLIO has the possibility of, in series, execute up to: - 40 different Level QC tests - 14 different FFT QC tests - 10 different MLS QC tests - 10 Polarity checks - 4 different Sinusoidal Impedance QC tests - 4 different Sweeps 15.4.1 LEVEL QC TEST Within the QC environment it is possible to define a level measurement with bargraph display (see figure 15.7).
A typical definition of a Level QC measurement is: [LEV] LEVOUT=0 LEVSINUS=1000 LEVUPPER=+3 LEVLOWER=-3 LEVLOOPMODE=1 ; ; ; ; ; generator output level test frequency upper limit lower limit loop mode activated In the case of level tests is mandatory to define the output level of the signal (LEVOUT); this is done in the first line of the example. It is also mandatory to specify a upper and lower limit; this is done in the third and fourth lines of the example.
15.4.1 FFT QC TEST A typical definition of a FFT QC measurement is: [FFT] FFTOUT=0 FFTIN=-10 FFTREFCURVE=ref.fft FFTREFLIMITS=fftabs.lim SINUS1=900 SINUS2=1100 PERCENT1=50 PERCENT2=50 ; ; ; ; ; ; fft output level fft input gain reference curve reference limits test frequency 1 test frequency 2 In the case of FFT tests is mandatory to define the output level of the signal (FFTOUT); this is done in the first line of the example.
FFTREFCURVE=ref.fft FFTREFLIMITS=fftabs.lim FFTSTIMULUS=\system\all1024.sig FFTACQUIDELAY=200 In this case we set the input sensitivity to a fixed +10 dBV, used the file "all1024.sig" (the alltone file relative to a FFT of size1024) as stimulus and let the signal play for 200 ms before starting acquisition. This setup was used to test in a very fast way the impedance of a midrange as reported in the side figure.
15.4.2 MLS QC TEST A typical definition of a MLS QC measurement is: [MLS] MLSOUT=0 MLSREFCURVE=ref.mls MLSREFLIMITS=mlsrel.lim ; mls output level ; reference curve ; reference limits In the case of MLS tests is mandatory to define the output level of the signal (MLSOUT); this is done in the first line of the example. It is also mandatory to specify a reference file and a limits file; this is done in the second and third lines of the example.
THE MLS GLOBAL LEVEL CHECK It is possible to define a MLS global level check that will allow precise comparison and test of the DUT sensitivity.
The two following situations try to explain the cases when a DUT is rejected; the first is bad frequency response while the second is bad sensitivity.
THE MLS STANDARD DEVIATION CURVES During a MLS QC test it is possible to calculate and visualize two standard deviation curves as in figure 15.8. FIGURE 15.8 - MLS test with standard deviation curves and limits display off. This two curves are calculated, at run-time, starting from all the MLS tests that executed good in the current QC session; each point of the curves is obtained from the mean value plus or minus two times the standard deviation.
15.4.3 POLARITY CHECK Immediately after the definition of a MLS test it is possible to execute a polarity check. The following example shows the definition of a relative polarity check: [MLS] .. .. .. [POLARITY] PHASE=REF The definition of a polarity check has to follow immediately a MLS test because it is done analyzing the time impulse response just measured.
15.4.4 IMPEDANCE QC TEST A typical definition of a Sinusoidal Impedance QC measurement is: [IMPEDANCE] IMPREFCURVE=ref.imp IMPREFLIMITS=impabs.lim ; reference curve ; reference limits In this case it is mandatory only to specify a reference file and a limits file. In the case of an impedance measurement the stimulus, output level, input gain and acquisition timing are univocal and controlled by the software. FIGURE 15.
THIELE/SMALL PARAMETERS QC CHECK It is possible to define a quality control test of some Thiele/Small parameters. This check has to be defined in the limits file using the IMPQUPPER and IMPQLOWER keywords for Qts and the IMPFSUPPER and IMPFSLOWER keywords for Fs; a limits file as an example follows: TYPE=ABSOLUTE [PARAMETERS] IMPREDC=5.2 IMPQUPPER=0.3 IMPQLOWER=0.
15.4.5 SWEEPS GENERATION AND CONTROL Sinusoidal sweeps for classical "ear-driven" tests can be easily defined in the setup file: [SWEEP] START=150 STOP=500 RESOLUTION=48 LENGTH=2 SWEEPOUT=6 ; ; ; ; ; Hz Hz sweep resolution in fraction of octave sweep length in seconds sweep output level A sweep is the only test that can be executed and repeated independently from the QC test sequence (see 15.5). During sweep generation several hot keys are active: ESC Immediately stops generation.
15.5 THE QUALITY CONTROL PANEL FUNCTION BUTTONS Referring to the QC control panel we have the following function buttons: Start Starts a quality control measurement. NOTE: The tests are executed in the same order as they are input in the setup file. Sweep Starts a sweep generation. It is usually disabled when in manual and not in interactive modes and when not in manual mode.
15.6 QC KEYWORDS REFERENCE 15.6.1 KEYWORDS USED IN SETUP FILES KEYWORDS FOR GLOBAL DEFINITIONS [GLOBALS] Initiates the global definitions of every setup file. COMPANY String used as the first title of the QC measurement panel. Usually the company name. TITLE String used as the second title of the QC measurement panel. Usually a description of the test setup. WORKDIRECTORY Directory under DATA\ where all the QC files are stored. INTERACTIVE =1 displays the result of each measurement and prompts.
PHANTOM =1 switches the phantom power supply on. =0 switches the phantom power supply off. If omitted defaults to 0 i.e. PHANTOM OFF. MANUAL =1 starts the QC tests manually (pressing the start button). =0 starts the QC tests on receipt of an external trigger signal. If omitted defaults to 1 i.e. MANUAL. STARTSIGLOGIC When not in manual mode defines the logic of the external trigger signal; =1 is active high. =0 is active low. If omitted defaults to 1 i.e. active high.
LEVSAMPLING Sampling frequency. If omitted defaults to 51200 Hz. LEVAVERAGE Integration time (Slow = 1 s, Fast = 125 ms, Imp = 31.25 ms). If omitted defaults to Fast. LEVREFERENCE Reference level for the measurement. The units in this case are dBRel. LEVUPPER Defines the upper measurement limit. LEVLOWER Defines the lower measurement limit. LEVLOOPMODE Loop mode for interaction with the user and DUT tuning.
FFTSAVEPROMPT =1 when in AUTOSAVE and in INTERACTIVE modes, prompts before saving if a file name has been specified with SAVENAME; otherwise the name of the file is generated automatically and the file is save without prompting. =0 when in AUTOSAVE saves without prompting If omitted default to 0 i.e. NO PROMPT. FFTTXTSAVE When in AUTOSAVE mode, saves the current measurement in a compact ASCII format.
MLSDISPLAYONBAD When not in interactive mode stops and displays a faulty measurement instead of continuing the sequence of tests. If omitted defaults to 0 i.e. not active. MLSAUTOSAVE =1 the measurement is saved automatically. =0 no measurement is saved. If omitted the default is NO AUTOSAVE. MLSSAVENAME Name of the file saved when in AUTOSAVE. If omitted the name of the file is generated automatically.
IMPDISPLAYONBAD When not in interactive mode stops and displays a faulty measurement instead of continuing the sequence of tests. If omitted defaults to 0 i.e. not active. IMPAUTOSAVE =1 the measurement is saved automatically. =0 no measurement is saved. If omitted the default is NO AUTOSAVE. IMPSAVENAME Name of the file saved when in AUTOSAVE. If omitted the name of the file is generated automatically.
MESSAGE Text of the user message. CUSTOM CONTROLS FOR THE CLIOQC AMPLIFIER&SWITCHBOX [SETINPUT1] Selects input 1 of the CLIOQC Ampli&SwitchBox. [SETINPUT2] Selects input 2 of the CLIOQC Ampli&SwitchBox. [SETINPUT3] Selects input 3 of the CLIOQC Ampli&SwitchBox. [SETINPUT4] Selects input 4 of the CLIOQC Ampli&SwitchBox. [SETINPUT5] Selects input 5 of the CLIOQC Ampli&SwitchBox. [SETINPUT6] Selects input 6 of the CLIOQC Ampli&SwitchBox. [SETINPUT7] Selects input 7 of the CLIOQC Ampli&SwitchBox.
KEYWORDS FOR DEFINING A SIGNAL OR DELAY [SIGNAL] Defines an unconditioned digital TTL signal. [SIGNAL ON GOOD] Defines an signal conditioned by the positive result of the previously executed measurement. [SIGNAL ON BAD] Defines an signal conditioned by the negative result of the previously executed measurement. [GLOBAL ON GOOD] Defines an signal conditioned by the positive results of all the executed measurement.
15.6.2 KEYWORDS USED IN LIMITS FILES COMPULSORY KEYWORDS TYPE =ABSOLUTE the limits curves are constructed from the absolute values defined in the limits files. =RELATIVE the limits curves are calculated starting from the reference file and then adding and subtracting the values of the limits. If omitted defaults to RELATIVE.
15.7 INTERACTING WITH EXTERNAL HARDWARE The interaction with an external hardware gives CLIO the possibility of realizing semi or fully automatic production lines QC tests. Several keywords have been introduced to implement this functionality (refer to the preceding section 15.6). 15.7.
15.7.2 EXTERNAL TRIGGER When not in manual mode it is possible to trigger the QC tests sequence with an external TTL signal (see also 15.2.2) wired to the PC parallel printer port. STARTSIGLOGIC defines the logic behaviour of the input signal (i.e. active high or low). PULSELENGTH defines the period of time (approximately in ms) for which the input signal has to be held active to be correctly detected. The following lines are needed in a setup file for connecting a push-button (Fig.15.
STATUS=1 [SIGNAL] LPTBIT=0 STATUS=1 DELAY=200 LPTBIT=0 STATUS=0 LPTBIT=1 STATUS=0 LPTBIT=3 STATUS=0 This example defines a signal high on bit 3 if the MLS test performs bad, a signal high on bit 1 if all the tests are OK and an unconditioned pulse of 200 ms on bit 0 that may be used to signal the end of the QC test sequence. Referring to Figure 15.11 we can see the time signal of the three bits in the two possible cases A and B; in case A the MLS test performed bad and in case B good.
15.7.4 TIME DELAYS GENERATION It is possible to define a time delay in any point of a setup file with the following definition: [SIGNAL] DELAY=200 In this example the QC sequence waits for 200 millisecond when encountering these keywords. In the previous paragraph you can see also the possibility of mixing time delays with signals definitions in order to generate pulses. 15.7.5 PARALLEL PORT SIGNALS MANAGEMENT The TTL signals generated with the active parallel printer port of the PC (see 7.4.
Chapter 15 – Quality Control Menu
BIBLIOGRAPHY [1] J.M. Berman and L.R. Fincham, “The Application of Digital Techniques to the Measurement of Loudspeakers,” J. Audio Eng. Soc., Vol. 25, 1977 June. [2] L.R. Fincham, “Refinements in the Impulse Testing of Loudspeakers,” J. Audio Eng. Soc., Vol. 33, 1985 March. [3] S.P. Lipshitz, T.C. Scott and J. Vanderkooy, “Increasing the Audio Measurement Capability of FFT Analyzers by Microcomputer Postprocessing,” J. Audio Eng. Soc., Vol. 33, 1985 September. [4] D.D. Rife and J.
[19] D. Clarke, “Precision Measurement of Loudspeaker Parameters”, J. Audio Eng. Soc., 1997 March. [20] IASCA - International Auto Sound Challenge Association Inc. - “Official Judging Rules”.
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