Comments on: Android audio applications http://www.endolith.com/wordpress/2009/11/24/android-audio-applications/ move along Mon, 23 Jan 2012 22:37:58 +0000 hourly 1 http://wordpress.org/?v=3.3.1 By: beun http://www.endolith.com/wordpress/2009/11/24/android-audio-applications/comment-page-1/#comment-8028 beun Fri, 29 Oct 2010 21:29:11 +0000 http://www.endolith.com/wordpress/?p=750#comment-8028 I just uploaded my own signal generator app for android. Its called FuncGen, if you want please check it out. I just uploaded my own signal generator app for android. Its called FuncGen, if you want please check it out.

]]> By: Endolith http://www.endolith.com/wordpress/2009/11/24/android-audio-applications/comment-page-1/#comment-7227 Endolith Fri, 16 Jul 2010 15:12:16 +0000 http://www.endolith.com/wordpress/?p=750#comment-7227 Yes, that's what I mean. It should look like a sine wave, but it doesn't. The spectrum should be only the frequencies that are present in a square wave, not the aliased harmonics from sampling an ideal mathematical square wave without filtering it first: http://flic.kr/p/83JMi6 http://flic.kr/p/83JMjT http://flic.kr/p/83Ekg2 Yes, that’s what I mean. It should look like a sine wave, but it doesn’t. The spectrum should be only the frequencies that are present in a square wave, not the aliased harmonics from sampling an ideal mathematical square wave without filtering it first: http://flic.kr/p/83JMi6 http://flic.kr/p/83JMjT http://flic.kr/p/83Ekg2

]]> By: beun http://www.endolith.com/wordpress/2009/11/24/android-audio-applications/comment-page-1/#comment-7226 beun Fri, 16 Jul 2010 15:08:04 +0000 http://www.endolith.com/wordpress/?p=750#comment-7226 The 10kHz square will always look bad since the sample rate is only 44.1kHz, there are only just over two samples in a 10kHz signal. After low pass filtering in the DAC it should look like a sine as the next harmonic (the 3rd) is already fully suppressed. To get a better indication of the square wave capability run it at 1kHz. I do agree with you that the frequency spectrum doesn't look right. There should be no sub-harmonics. The 10kHz square will always look bad since the sample rate is only 44.1kHz, there are only just over two samples in a 10kHz signal. After low pass filtering in the DAC it should look like a sine as the next harmonic (the 3rd) is already fully suppressed. To get a better indication of the square wave capability run it at 1kHz.

I do agree with you that the frequency spectrum doesn’t look right. There should be no sub-harmonics.

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