Low Frequency Detector vs GPS Speedometer

"Low Frequency Detector" is an acoustic measurement tool for detecting low-frequency sounds that is hard to hear in normal situation. The human ear is not sensitive enough to low-frequency sounds. If you are exposed to noise from nearby construction or factories without realizing it, you may feel discomfort or a sense of pressure. In such cases, you can use this app to check what kind of low-frequency noise is present. Generally, low-frequency sounds is a sound wave ranging from 1Hz to 100Hz. Depending on its frequency component and sound level, the degree of influence on the human body and the noise sensation is different. This app allows you to examine the frequency component of low-frequency sounds by 1/3 octave band analysis and FFT analysis. Features: - Low-frequency power level measurement less than 100Hz (LF Level): Flat characteristic, Updating indication of measurement period 1 sec. - Power level measurement in the audible band (Leq): Flat characteristic, Updating indication of measurement period 200ms. - 1/3 octave band analysis (OCT) - FFT analysis (FFT) - Time course graph (TIME) - Snapshot (Snap) on the measurement display screen. - Report function (Report): Analysis report of a peak LF Level with TIME, OCT and FFT. - Measurement time: up to 60 sec Functions: The measurement analysis is performed in the following step. Be sure to set the measurement conditions in Step-1 once before starting the sound measurement. 1) Calibration (Calibrate): The reference signal (1kHz sine wave) is output to determine the reference noise level for the low-frequency component. If the volume level of iPhone is set to about 20-50%, the calibration will automatically adjust it to the optimum volume level for the reference signal. 2) Measurement (Measure): Analyze a power level of low-frequency sounds. - LF Level (dB): Low-frequency power level less than 100Hz. - Leq (dB): Sound power level with the frequency weight characteristic Z (Flat) of the audible band. 3) Measurement display: It can select either 1/3 octave band frequency analysis, FFT analysis or Time course graph. They are updated in real time. 4) Report: Measurement result report. It is effective when measuring for 10 seconds or more. # Time course graph: TIME - Low-frequency (LF) Level (dB): Time course graph with peak level noise level judgment (RED-very noisy, YELLOW-noisy, GREEN-normal) at the peak level. - LF max (dB): maximum dB value of low frequency. # Frequency response graph: OCT, FFT - OCT Band LF max (dB): maximum dB value in 1/3 octave band at LF max observation. - Max Level Frequency (Hz): peak frequency at LF max observation. Notes: - The sound measurement of the low-frequency range is a level difference with respect to the reference signal, which indicates the relative power level. - The reference signal is output during calibration and sound level measurement. - Do not change the volume level of iPhone after the calibration. - White line in the OCT and FFT modes indicates frequency characteristics in frequency weight correction of G characteristics. - Since iPhone's built-in microphone has a lower sensitivity on the very low frequency range, it is not recommended to measure a huge volume sound near a very loud noise source. - Since it takes a while for the observation value to stabilize immediately after the start of measurement, the maximum value is calculated from about 2 seconds later. - In the case high power of 1kHz component is included in the measured noise source, the precision of measured value by this app largely decreases. - Sudden noise or impulsive sounds are not low frequency noises in general. - The previous calibration information can be maintained internally. - The analysis results may vary due to individual differences in iPhone devices. - The authorization to access built-in microphone and Photos will be confirmed by iOS system at first access. Please visit our iOS app support page for more information.

See your speed. Track your distance. Remember your journey. SpeedNow turns your iPhone into a clear GPS speedometer and a simple companion for everyday trips. Whether you are cycling, commuting, or exploring somewhere new, see your current speed, follow your distance, and keep track of how long you have been on the move. From a short ride around the neighborhood to a longer day out, SpeedNow brings your trip essentials together in an easy-to-read interface. Start a ride, check your progress, pause when you take a break, and stop when you reach your destination. YOUR SPEED AT A GLANCE Watch your current GPS speed on a dedicated speedometer display. A large speed reading and visual gauge make it easy to understand your pace at a glance. Choose a maximum speed for the gauge that suits your journey, so the display feels right for the way you travel. CHOOSE THE UNITS THAT WORK FOR YOU Switch between kilometers per hour, miles per hour, and knots in Settings. Distance uses the matching units: kilometers, miles, or nautical miles. Whether you think in metric or imperial measurements, your speed and distance stay easy to read. TRACK DISTANCE AND TIME See your distance and elapsed trip time alongside your speed. Keep the essentials in view without switching between separate tools. SpeedNow gives you a straightforward way to follow the trip you are taking, from the moment you start until you finish. PAUSE WHEN YOU NEED A BREAK Taking a rest or stopping along the way? Pause your ride and resume when you are ready to continue. Simple ride controls let you manage each journey without turning a quick stop into a separate ride. KEEP YOUR DISPLAY READY Turn on Keep Screen Awake to prevent your iPhone from automatically locking during a ride, including while the ride is paused. Set your preferred units and gauge scale in Settings to make the speedometer fit your routine. GO FURTHER WITH SPEEDOMETER PRO Unlock the map, saved ride details, and ride sharing with Speedometer Pro. FOLLOW YOUR ROUTE LIVE Open the map during a ride to see your location and the route you are recording. View the path as your journey unfolds, check distance and duration beneath the map, and recenter the view on your location with a tap. Move between the speedometer and map depending on what you want to see. REVISIT YOUR RIDES Completed rides appear in History, making it easy to find previous journeys. With Pro, open a saved ride to view its recorded route, distance, and duration. Look back at where you went, revisit a familiar outing, or keep a record of the trips you want to remember. Remove rides from History when you no longer need them. SHARE THE JOURNEY Create a ride summary image from a saved ride and share it through your iPhone's sharing options. Bring your route and trip details together in one image, whether you want to send a ride to a friend or save a visual reminder of your day out. SIMPLE TO MAKE YOUR OWN Use kilometers per hour for one journey or miles per hour for the next. Change the gauge scale, choose whether the screen stays awake, and switch between your current ride and past trips. SpeedNow keeps these everyday controls close at hand, so you can spend less time setting up and more time enjoying your journey. Keep a useful record of your everyday travel, from a daily commute to a route you have never tried before. Each completed ride gives you a new journey to revisit and, with Pro, share with friends. START YOUR NEXT TRIP WITH SPEEDNOW A clear speed display, practical ride controls, and distance and time tracking give you the essentials for everyday use. Add Speedometer Pro when you want to follow your route on the map, explore saved ride details, and share your journeys. Map access, saved ride details, and ride sharing require Speedometer Pro. GPS speed and route recording require location access. Privacy Policy: https://speednow.app/privacy/ Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/