Audio artifacts

[Stephen Prior]

When I turned the K3 on tonight with AFX on and wearing headphones I could
hear some slight high frequency roughness on the audio as if there were a
problem with the headphones being overdriven.  They were not, and are in
fact an expensive pair of Sennheisers.

I turned the K3 off and then on again and they were still there. However the
problem disappeared completely on adjusting the filter width and has not
come back since.

I am using latest firmware on K3 no. 980.  (Where is the hash key on a Mac
keyboard??!!)

73 Stephen G4SJP



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[Stephen Prior]

It's okay, I've found it!  #980!


On 20/06/2008 20:32, "Stephen  Prior" <[hidden email]> wrote:
<snip>
 
> (Where is the hash key on a Mac keyboard??!!)
>
> 73 Stephen G4SJP



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[KK7P]

> When I turned the K3 on tonight with AFX on and wearing headphones I could
> hear some slight high frequency roughness on the audio as if there were a
> problem with the headphones being overdriven.  They were not, and are in
> fact an expensive pair of Sennheisers.
>
> I turned the K3 off and then on again and they were still there. However the
> problem disappeared completely on adjusting the filter width and has not
> come back since.

Also, if SPKR+PH is ON and SPKRS =1, the forced combining of AFX outputs
can cause this sort of effect.

73,

Lyle KK7P

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[John W2XS]

I had some audio distortion while listeining to AM when I set the some of the AGC settings at maximum (based on a recent post). Backing off on the settings made the audio crystal clear.

73,

John W2XS

Stephen Prior wrote

When I turned the K3 on tonight with AFX on and wearing headphones I could
hear some slight high frequency roughness on the audio as if there were a
problem with the headphones being overdriven.  They were not, and are in
fact an expensive pair of Sennheisers.

I turned the K3 off and then on again and they were still there. However the
problem disappeared completely on adjusting the filter width and has not
come back since.

I am using latest firmware on K3 no. 980.  (Where is the hash key on a Mac
keyboard??!!)

73 Stephen G4SJP



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[Stephen Prior]

It's the first time I've noticed this problem.  I assume Lyle that you are
not suggesting that it's a by-product of using the AFX, because I use AFX
all the time and had not noticed it before.  I don't have the settings for
SPKR+PH _and_ SPKRS=1 on.

73 Stephen G4SJP


On 20/06/2008 20:55, "Lyle Johnson" <[hidden email]> wrote:

>> When I turned the K3 on tonight with AFX on and wearing headphones I could
>> hear some slight high frequency roughness on the audio as if there were a
>> problem with the headphones being overdriven.  They were not, and are in
>> fact an expensive pair of Sennheisers.
>>
>> I turned the K3 off and then on again and they were still there. However the
>> problem disappeared completely on adjusting the filter width and has not
>> come back since.
>
> Also, if SPKR+PH is ON and SPKRS =1, the forced combining of AFX outputs
> can cause this sort of effect.
>
> 73,
>
> Lyle KK7P
>
>

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[KK7P]

> It's the first time I've noticed this problem.  I assume Lyle that you are
> not suggesting that it's a by-product of using the AFX, because I use AFX
> all the time and had not noticed it before.  I don't have the settings for
> SPKR+PH _and_ SPKRS=1 on.

AFX provides a delay between the two channels. If the channels are then
summed, there will be peaks and nulls depending on the pitch.  The same
thing happens if you have two speakers in a room with hard walls and no
draperies.  It is not distortion, it is combining signals that are no
longer in phase due to the intentionally introduced delay.

73,

Lyle KK7P


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[Stephen Prior]

I hear what you are saying Lyle, and maybe I didn't explain myself clearly
enough- what bothered me was that moving filter bandwidth from 2.7 to 2.8kHz
and then back again completely stopped what I was perceiving as distortion.
That is what made me wonder if it were something amiss somewhere.

It's not there now anyway.

73 Stephen


On 20/06/2008 22:02, "Lyle Johnson" <[hidden email]> wrote:

>> It's the first time I've noticed this problem.  I assume Lyle that you are
>> not suggesting that it's a by-product of using the AFX, because I use AFX
>> all the time and had not noticed it before.  I don't have the settings for
>> SPKR+PH _and_ SPKRS=1 on.
>
> AFX provides a delay between the two channels. If the channels are then
> summed, there will be peaks and nulls depending on the pitch.  The same
> thing happens if you have two speakers in a room with hard walls and no
> draperies.  It is not distortion, it is combining signals that are no
> longer in phase due to the intentionally introduced delay.
>
> 73,
>
> Lyle KK7P
>
>
>

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