【實用工具app】SPLnFFT Noise Meter|最夯免費app-綠色工廠好玩App

SPLnFFT is a noise meter (or sound meter) with many extra features: frequency analyzer, frequency meter, test signal generator, dosimeter, ...For daily use, a very simple interface displays the level of exposure: if orange or red, protect your ears !Advanced users will have access to a wide range of measurements: Leq, peak, L10, L95, taktmaximal, frequency analysis, histogram, dosemetering, ... A&C; weightings are compliant with ANSI® S1.42 standard. "468" refers to ITU-R 468-4Here are extracts from reviews:"our favorite sound measurement app" SafetyAwakenings.com"SPLnFFT is comprehensive, easy to use" TapeOp.comThe only soundmeter App on iOS recommended by the "Laborers' Health and Safety Fund of North America" !Other reviews are listed here: https://www.facebook.com/SPLnFFTSome critical information:- you absolutely need to allow access to microphone to use this App- screen rotation must be un-locked- there are built-in help messages (speech bubble). Need more ? Contact me !: email, blog, Facebook,... Indeed I cannot answer to comments on iTunes- in very - very - rare occasions App fails to install: just delete it completely and re-install it !Top digital display is for measurement of sound power in 'slow' mode (averaged on 1s). Central analog display is for 'fast' mode (averaged on 1/8th s). But it can display 'slow' mode as well on request: just click on 'fast' label.Peak and average values are displayed below and are holded until you touch the 'reset' label.Bottom view is a real time FFT. You will notice that predominant frequency and next one are highlighted. Their frequencies and relative power are displayed on the right. If your input signal is a pure tone then this App will lock on its frequency and display a very accurate result.Green line is the result of a real time FFT done with 1024 points. Purple line is the averaged FFT (exponential filtering done on power of each frequency). Blue line is a copy of what the purple line was when the user froze the display the last time.A test tone at 1kHz or a white noise or a pink noise can be generated and sent to right and/or left outputs (select the type you want in BEEP tab). This FFT view - more precisely an upsized version of it - can be exported as a picture in your own photo library, using the camera button (when display is frozen only). This picture can be exported in a mail as well, or to social networks (when available and configured).The display can be flipped upside-down to ease reading: just rotate your iPhone while holding it vertically.Very sensitive: for example it can detect a CRT TV (*) at a distance of few meters ! A dedicated flag is raised to warn you in such situation.(*): CRT = not Plasma nor LCDAs for ALL sound meters (thus including this one and all others at any price), calibration is suggested if you want to reach extreme precision. This is enabled in this App thanks to a slider to apply some compensation and to three non volatile memories (choice to be made in MIKE tab). How to ? For calibration, you need and external reference, either a calibrated sound meter, or a calibrated noise source.Note as well that the tiny embedded loudspeaker cannot reproduce extreme frequencies. Thus if you want to hear a real white or pink noise, you will need to use a quality headphone or HiFi system.This App was designed seriously for my own needs. I am a signal processing expert and you will find other audio applications from myself in AppStore.***** Any comment, any feedback ? Click on 'support' in iTunes: there is a blog for this. You can even contact me directly by email *****