Using the Panasonic WM6. A as a Measurement Microphone. Measurement microphones are an indispensable tool for the. Measurement microphones. Hz., and above 2. Hz., and do not have weighted, or equalized frequency. They are also optimized for measuring high SPL. Revus builtin measurement tools make it easy to take length, area, perimeter, diameter, volume and radius measurements, count from PDFs and perform area. Silhouette Studio Designer Edition 13 Reasons Why Its Worth the Upgrade. Draw and Paint with Digital Tools Crayola Art Studio. Core Learning has partnered with Crayola to produce an outstanding art software program for children. Measurement microphones are an indispensable tool for the musician and soundrecording engineer. Measurement microphones differ from recording microphones. Smaart v8 is the Industry Leading, Dual Platform Mac PC, FFTBased Audio Analysis Software. At its core, Smaart is a computer based dualchannel FFT platform that. MSU Video Quality Measurement Tool VQMT is a program for objective video quality assessment. It provides functionality for both fullreference two videos are. PML is a world leader in the science of measurement. We determine the definitive methods for nearly every kind of measurement employed in commerce and research. The Legion simulation system predicts, measures and displays actual human movement within existing and unbuilt venues, to improve design and operational effectiveness. Measurement microphones retail for US 1. US 5. 00. but very adequate measurement microphones can be made using. Panasonic WM6. 1A. Digi Key, part number P9. ND. for under US 2. For simple measurements, i. SPLs. greater than 6. MvBR54on9k/Tu17wNg97SI/AAAAAAAAAAM/dUCsqRTcr0o/w1200-h630-p-k-no-nu/untitled.bmp' alt='Measurement Studio License' title='Measurement Studio License' />B, and less than 1. B, the WM6. 1A. can be interfaced directly to a PCs sound Figure I. Interfacing the Panasonic WM6. A Electret Microphone to the Sound. Blaster CT4. 81. 0 PC Sound Card. Figure I, which is available in larger size jpeg. Panasonic. Electret Microphone cartridge to the Sound. Blaster CT4. 81. 0 PC. Sound Card, including approximate signal voltage levels. The WM6. 1A. is quite small, 6 mm in diameter, 4 mm height, and a. Figure II. Construction of a Measurement Microphone Using the Panasonic WM6. Lego Indiana Jones 1 Torrent Pc Games. A Electret Cartridge. Figure II, which is available in larger size jpeg. Measurement Microphone. Panasonic WM6. 1A. Electret cartridge. The electret cartridge should be covered. I use GEs Silicon II, Household. Glue which is available in the paint department of home. The wires. should be soldered to the cartridge first, cut to length, and. The measurement microphone is specified at 3. B 4 d. B. 0 d. B 1 V Pa, with an load resistance of 2. K, and 1 Pa. is 9. B SPL. or 9. 4 d. B SPL. produces 1. V across the 2. 2. K load resistance, 9 m. V across. two 2. 2. K resistors in parallel 1. K. Note with a load. K resistors in parallel, or 1. K, and. the tip and ring shorted, 1. B SPL. produced a measured 1. V signal at input to the sound card. B FS. Figure III. WM6. 1A Typical Frequency Response. Figure III is a plot of the frequency response of a typical. Note that the unequalized response is flat to 1. B to 2. 0. k. Hz. However, there appears to be a zero in the transfer. Hz., causing the response to be high by. B at 7. 5 k. Hz., which could be canceled in the. Hz. The microphone is quite good, within its SPL. Baudline FFT. time frequency browser designed for scientific visualization. Xoscope, turning. PC into an audio analysis system. Ray Carlisle. has developed a Spicecircuit. WM6. 1A. electret microphone using LTSpice. Linear Technology. The. simulations agree reasonably well with the empirical. Ruslan Migirov contacted the Panasonic corporation. FET part number for the Japanese version of the WM6. A. is 2. SK1. 23. For the US version of the WM6. A. the FET part number is 2. SK3. 37. 20. RLCT ND. Amplifier for the Panasonic WM6. A. Electret Microphone Figure IV. Schematic of the Amplifier for the Panasonic WM6. A Electret Microphone. Figure IV, which is available in larger size jpeg. Panasonic. Electret Microphone. Almost any operational amplifier will. JFET gain is quite high, so amplifier noise. Linear Technology. LT1. 67. 7. is a good choice because of its common mode input range. They are. available on the Linear. Technology site for under US 3. A less expensive. TLC2. 72. from Texas Instruments. It is. a dual, the other channel is not used and may be used as a. Newark for under US 0. It is a linear CMOS design, and has inferior noise. Hz. range, compared to the. LT1. 67. 7. but may be acceptable for high SPL. The TLC2. 72. can also drive line levels, i. Bu 0. 7. 75 V RMS across. Bm 0. 7. 75 V RMS across 6. Ohms 1 m. W 1. B. FS, as per EBU R6. Ohm resistor in the. Ohms. total. The amplifier circuit is adaptable the only modification. JFET load resistor. It should be selected such that the worst. A, for the 2. SK3. JFET, should pull. V below. the rail for common mode input operation of the operational. Likewise, the worst case maximum idss, 4. A, for. the 2. SK3. JFET, should not pull the voltage across the load. V above ground, for all. This is a very conservative circuit design over. An alternative. electret cartridge interface is shown that is DC coupled to. The WM6. 1A. data sheet does not offer worst case temperature. DC coupled bias circuit can not be determined. Also shown is a simple gain trim, for the 4 d. B gain. tolerance of the WM6. A,. that replaces the 2. K resistor and 1. F capacitor in the. Figure V. Complete Schematic of the Amplifier for the Panasonic WM6. A Electret Microphone. Figure V, which is available in larger size jpeg. Panasonic WM6. 1A. Electret Microphone. The component bill of materials is about. US 1. 0, and all components are available on line. Note the use. of 4. V, 3 X AA batteries which can be rechargeable. Direct. Coupled Stereo Headphone Amplifier. Note, also, that no. MTBF. characteristics. Alternatively, the power could be provided by. PC sound card, 5 and 1. Volts are available from the. PC power supply. busses. Also, if 6 Volts can be used, 4 X AA batteries, a 3. Volt tap can be used for an artificial ground for the. F polyester capacitor which is the most. Figure VI. Alternative Schematic of the Amplifier for the Panasonic WM6. A Electret Microphone. Figure VI, which is available in larger size jpeg. Panasonic WM6. 1A. Electret Microphone. The component bill of materials is a. US 1. 0, and all components are available on. The 1f noise break frequency of the WM6. A. cartridge is about 5. Hz., as measured by Baudline, which is about. TLC2. 72. making the noise contributed by the operational amplifier. This is probably the simplest schematic. Figure VII. A More Elaborate Schematic of the Amplifier for the Panasonic WM6. A Electret Microphone. Figure VII, which is available in larger size jpeg. Panasonic WM6. 1A. Electret Microphone. The component bill of materials is still. US 1. 0, and all components are available on line. BOM consists of fairly high quality components that are easy. TL4. 31. shunt regulator to provide a stable, above ground, reference. Only one of the TLC2. TL4. 31. A gain trim can be added by reducing the value of the 2. K. resistor, and adding a potentiometer connected as a rheostat. TL4. 31. Note that the bandwidth is limited at the input, directly. WM6. 1A. cartridge, with poles at 5 Hz. Abbyy Finereader 11 Serial Key. Hz. The other two. As an alternative power supply, the amplifier. Volt Wall Wort, an. Note there are substantial variations in the amplifier. WM6. 1A. has a low enough frequency response to be used as a. Panasonic WM6. 1A. Electret Microphone There are several alternatives for removing the SPL. Panasonic WM6. 1A. Siegfried Linkwitzremoves. JFET amplifier. transistor in the cartridge. Ideally, it should be a constant. But there is a simple way to cancel the non linear. JFET amplifier. From semiconductor device physics, the id vs. JFET. id idss 1 vgs vpo2. If the load of the JFET microphone amplifier, Q1, is. JFET, Q2, in a cascode circuit topology, i. Rl, which is about 2. K, replaced with a. JFET, as shown in Figure VIII, below. Meaning, the gain, G vgs. JFET. transistors, Q1 and Q2, do not have to be matched the only. Figure VIII. Linearizing the Panasonic WM6. A Electret Microphone. Figure VIII, which is available in larger size jpeg. Panasonic. Electret Microphone. From the 2. SK3. 37. JFET data sheet, 1. A lt idss lt. A, as a worst case design at 2. C which will be much. B worst case specification for the WM6. A,. and from the typical graph for id vs. V lt vpo lt 0. V. G, is 2. 20. 0. G lt 2. G lt. 6. 8. 9. Note that Panasonic is probably cherry picking. SK3. 37. 2 JFET for 4 d. B tolerance, since they.