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I am generating an audio signal on a 12bit DAC I'm reading from a 16bit .wav file. My processor is 3.3V so I shift everything up 32768 so my values swing between 0-3.3V centered around 1.65V and shift it right 4 bits so I have 12bit values.

The trouble I'm having is when I turn on the DAC I get that loud pop when my amplifier sees that step function. I have an RC low pass filter on there now with a corner frequency of 4KHz and it isn't doing me much good.

I would like to fix this in hardware if I can but I can't think of the best way to do that. These are just voice commands played on a mono speaker so I don't need fantastic fidelity or anything.

The other solution I thought of was to ramp the DAC up and down but I would like to avoid the extra time that will take.

Any suggestions?

lusher00
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1 Answers1

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My DAC is constantly running through a 16 slot circular buffer so I just prefill it with my DC bias value before I start the audio and fill it again at the end of any audio I play. This removed the step functions and things sound great now.

lusher00
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