adcHighPassFilterEnable();

Status
Not open for further replies.

Klemen96

Member
Hello guys,

I am doing some audio project with tennsy 3.2 + audio board. Now i've calibrated microphone on audio board and adjuted to show the decibels. I think that works quite fine.
I also found option "adcHighPassFilterEnable();". If I understand correctly, this function is used by default, even if I don't use it and it cut the low frequency noises?

Does it works like A-weighting? Can I somehow set the border frequency of filtering (in case if cuts "too much").

""By default, the analog input (either line-level inputs or mic) is high-pass filtered, to remove any DC component.""

Every answer will be helpfull.

Best regards,
 
Personaly, I always disable that ADC filter as I find that it adds unacceptable noise to the system. See my post on this issue here:

http://openaudio.blogspot.com/2017/03/teensy-audio-board-self-noise.html?m=1

If you choose to disable the adc's highpass filter, you will have a small DC offset in your audio stream. You can remove this by adding a highpass filter using one of the filter blocks in the Teensy Audio Library (or using your A weighting filter, which also filters away DC). I have no problem with filtering; I only have a problem with the specific implementation of the HP filter used by default in the ADC.

Chip
 
Status
Not open for further replies.
Back
Top