Hello,
I am working on the DSK5510 board that has the AIC23b audio codec. When
I do a simple audio loopback, I see that there is attenuation at the
output below 400Hz. The audio output seems to be at a stable maximum
value beyond 400Hz. But, between 1Hz to 400Hz, there is a roll-off.
Has anybody seen this before? Is this high-pass effect being introduced
by the audio codec?
On the schematic of the DSK5510 board I do see capacitors (AC coupling)
that are connected both at the input and output audio channels. That is,
there are caps connected between the audio input jack and the audio
input pin of the codec. There are caps also connected between the audio
output pin of the codec and the audio output jack. I am not sure if this
is causing the high-pass effect?
Could you please tell me what is actually causing this? I would be more
than happy to try a few things and provide more information if you have
a clue.
Thanks,
Meenakshi.
Audio codec AIC23 on DSK5510 board
Started by ●August 4, 2005
Reply by ●August 5, 20052005-08-05
Hello,
The DSK manual and the datasheet for the audio codec do not explicitly
state any "working" frequency range. Infact, in the codec's datasheet
there are a few DAC and ADC filter response curves which actually go
down to DC without showing any kind of attenuation.
-Meenakshi.
>hi,
>
>yes, those series capacitors are a bit concern..
>you need to check with the dsk manuals to see if there
>is any specifications given for the low frequencies.
>further, you may also look at the aic23 codec data
>sheet itself for the same kind of specifications.
>
>it is very well possible that you may find the answer
>in these docs...
>
>regards,
>Dileepan.
>--- Meenakshi Matai <mmatai@mmat...> wrote: >
>>Hello,
>>I am working on the DSK5510 board that has the
>>AIC23b audio codec. When
>>I do a simple audio loopback, I see that there is
>>attenuation at the
>>output below 400Hz. The audio output seems to be at
>>a stable maximum
>>value beyond 400Hz. But, between 1Hz to 400Hz, there
>>is a roll-off.
>>Has anybody seen this before? Is this high-pass
>>effect being introduced
>>by the audio codec?
>>On the schematic of the DSK5510 board I do see
>>capacitors (AC coupling)
>>that are connected both at the input and output
>>audio channels. That is,
>>there are caps connected between the audio input
>>jack and the audio
>>input pin of the codec. There are caps also
>>connected between the audio
>>output pin of the codec and the audio output jack. I
>>am not sure if this
>>is causing the high-pass effect?
>>Could you please tell me what is actually causing
>>this? I would be more
>>than happy to try a few things and provide more
>>information if you have
>>a clue.
>>
>>Thanks,
>>Meenakshi.
>>
>>
>>
>>
>>
>>
>>
> >__________________________________________________
> >
The DSK manual and the datasheet for the audio codec do not explicitly
state any "working" frequency range. Infact, in the codec's datasheet
there are a few DAC and ADC filter response curves which actually go
down to DC without showing any kind of attenuation.
-Meenakshi.
>hi,
>
>yes, those series capacitors are a bit concern..
>you need to check with the dsk manuals to see if there
>is any specifications given for the low frequencies.
>further, you may also look at the aic23 codec data
>sheet itself for the same kind of specifications.
>
>it is very well possible that you may find the answer
>in these docs...
>
>regards,
>Dileepan.
>--- Meenakshi Matai <mmatai@mmat...> wrote: >
>>Hello,
>>I am working on the DSK5510 board that has the
>>AIC23b audio codec. When
>>I do a simple audio loopback, I see that there is
>>attenuation at the
>>output below 400Hz. The audio output seems to be at
>>a stable maximum
>>value beyond 400Hz. But, between 1Hz to 400Hz, there
>>is a roll-off.
>>Has anybody seen this before? Is this high-pass
>>effect being introduced
>>by the audio codec?
>>On the schematic of the DSK5510 board I do see
>>capacitors (AC coupling)
>>that are connected both at the input and output
>>audio channels. That is,
>>there are caps connected between the audio input
>>jack and the audio
>>input pin of the codec. There are caps also
>>connected between the audio
>>output pin of the codec and the audio output jack. I
>>am not sure if this
>>is causing the high-pass effect?
>>Could you please tell me what is actually causing
>>this? I would be more
>>than happy to try a few things and provide more
>>information if you have
>>a clue.
>>
>>Thanks,
>>Meenakshi.
>>
>>
>>
>>
>>
>>
>>
> >__________________________________________________
> >
