![]() In principle on Windows Vista and later you can force Audacity to request the sample rate direct from the device without Windows interfering with its own resampling by choosing “Windows DirectSound” host in Audacity and both “Exclusive Mode” boxes in Windows Sound. Unfortunately you don’t give your version of Audacity or Windows (see the pink panel at the top of the page). This is an extremely complex issue, but see this answer I wrote in response to a similar question. Don’t rely on Actual Rate being free of bugs. ![]() “Actual Rate” when recording aims to show the rate communicated by the sound card to Audacity. “Actual Rate” in the right-hand section of the Audacity Status Bar at the bottom aims to shows (when playing) the rate being communicated by Audacity to the sound card. MME host resamples everything to and from 44100 Hz, so if you choose MME you are getting the device’s current rate (if not 44100 Hz) resampled to 44100 Hz by Windows, then resampled to 384000 Hz by Audacity. Doing a recording at 384000 Hz I can with my low grade microphone se spectral peaks at up to 86 kHz.Īs Steve says, it is not as simple as the drivers determining the sample rate - the audio “host” API that you choose in Audacity’s Device Toolbar makes a big difference. Now I don’t believe that my sound card (AMD High definition audio device, Realtek High definition audio or Intel display sound?) supports that rate so I believe Audacity increases the sample rate by interpolation. Recording sound in Audacity I can select several sampling rates, the highest being 384000 Hz. If a cheap sound card says that it supports 192 Hz, it is probably “bending the truth” and referring to a resampled rate. If you are lucky, the hardware specifications may tell you what sample rates are supported by hardware, but sadly, for the sake of advertising hype, such information is often not available, or misleading. The only thing that Audacity cares about is that it gets the data.Īs you are probably aware, there is generally no point in selecting a sample rate that is higher than the sample rate supported by the hardware. Depending on the operating system version and the sound system API being used (whether you are using MME, DirectSound, ASIO, WASAP, or whatever), resampling may be available there. Some sound card drivers are able to resample. Some ADC support multiple rates in the actual hardware. There are various places that resampling may occur if the requested stream does not match a rate that is supported by the ADC. When the computer system (operating system) receives a request from an application to provide an audio stream at a specified rate, the system will request audio data stream from the audio device. If the computer system is unable to send audio to Audacity, Audacity will raise an error message to check the sample rates. Audacity just requests what it wants and records what the computer system sends it. The “actual” sample rate that is used by the analog to digital converter (ADC) in your audio device, is unknown to Audacity. When recording, Audacity requests audio at the “project rate” (bottom left corner of the main Audacity window), unless you are “append recording” into an existing track, in which case the track sample rate is used. The “real” sample rate depends on where you are looking. ![]() ![]() How can I determine the real samplingrate? There is something called ASIO4ALL that will work with Realtek, but it’s “half-ASIO” (it replaces part of the Windows driver stack) and I’m not sure if it actually “locks into” the hardware’s sample rate. Audacity also doesn’t support ASIO as distributed, and there won’t be ASIO drivers for your Realtek hardware. (Real ASIO only works at the hardware sample rate.)Īudacity doesn’t support ASIO as-distributed, and unfortunately Audacity can only use WASAPI to record playing/streaming audio (not directly from your soundcard). I think you have to use WASAPI drivers or ASIO drivers, but again I don’t know how to configure WASAPI to “lock-into” the physical sample rate. There might be a way to know, but I don’t know how to do it. I doubt your soundcard/soundchip can really sample at 384kHz, and your “cheap” microphone certainly can’t go much above 20kHz, if it can even do that! It will also happily print an image of lower resolution than the printer’s actual DPI resolution with the drivers quietly doing the conversion in the background. Your printer will happily print an image that has higher resolution than your printer is capable of and you won’t get any kind of warning… It just “works”. I don’t know… Your DRIVERS will do the conversion for you, so it’s hard to know what the physical sample rate is…
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