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Thread: Audio Hacker to Teensy 3.2

  1. #1
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    Audio Hacker to Teensy 3.2

    Hi guys,

    I'm pretty new to the Teensy / Arduino, though I normally use PIC CPUs in my designs. I've got an Uno and a Teensy 3.2 that I've been playing with and it's an amazing experience.

    I bought a Nooptropic Audio Hacker and have it running on the Uno. I'd like to make a board that uses the Teensy CPU since it already has a 12 bit A/D and D/A instead of the individual chips on the Audio Hacker. In the Audio Hacker project, I tried changing the target board to the Teensy just to see if it would compile and get all sorts of errors and I could use some help sorting them out.

    Is my idea even possible? Any help appreciated.

    Doug

  2. #2
    Senior Member PaulStoffregen's Avatar
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    Please take a look at this tutorial for using the Teensy Audio Library.

    https://www.pjrc.com/store/audio_tutorial_kit.html

    It's 31 pages and there's a full walkthrough video if you scroll down a bit.

    Yeah, this is a totally different approach than Nooptropic. Generally it's much, much better. And if you *really* want to get access to the raw audio data, you can with the "queue" objects. Those aren't covered in the tutorial, but you can find them documented in the design tool.

  3. #3
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    Thanks Paul.

    I already have the audio board and it sounds great. My goal is to have a hardware sampler that can record, as well as playback at variable speed, forward and reverse, which is my reasoning for looking at the Audio Hacker. They have sampler code that does speed control (forward only though). Do you think that's possible with Teensy?

  4. #4
    Senior Member PaulStoffregen's Avatar
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    Variable speed is difficult for a fixed sample rate system. It's on my todo list. The really hard part is playing faster. The high frequencies cause nyquist aliasing.

  5. #5
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    I've seen references to that and I'm familiar with the basics of Nyquist, but do you know of any articles that might explain the difficulties and possible solutions when playing faster?

    My needs are not CD quality (though it would be nice). A ~6KHz playback bandwidth would be OK for my application, and I can live with 12 bits.

  6. #6

  7. #7
    I have the same problem with you. Until now I cannot control it.

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