Posted by Smarty on 04/28/07 01:50

If what you are experiencing is truly sibilance, the very specific unnatural
emphasis given to fricative sounds like "s" and "f", rather than distortion,
the likely culprit is an uneven frequency response which places undue
emphasis on mid to high frequency energy somewhere in the modulation chain.
It is commonly associated with devices which have very irregular
frequency/phase characteristics, such as a microphone with a very peaked
response in the upper vocal frequencies, or an equalization curve which has
been improperly set. Companders and modulators are not the typical cause,
although a defect in either can cause excessive treble exaggerations which
produce sibilance on fricative sounds.

As nappy states, you will need to get into the modulation chain at
intermediate points with a scope, a reliable reference playback system, or
both, while driving the system with a known, balanced audio source. There is
no way to easily diagnose the problem otherwise, at least not that I am
aware of.

Smarty

"Rick Merrill" <rick0.merrill@NOSPAM.gmail.com> wrote in message
news:fo2dnUOF4ek19q_bnZ2dnUVZ_jWdnZ2d@comcast.com...
> nappy wrote:
>> "Rick Merrill" <rick0.merrill@NOSPAM.gmail.com> wrote in message
>> news:YYKdnXtRaNbzoq_bnZ2dnUVZ_tidnZ2d@comcast.com...
>>> Richard Crowley wrote:
>>>> "Rick Merrill" wrote ...
>>>>> My TV station (PEG/public access) has a lot of similiance.
>>>>> There is a CADCO modulator after an MTS-4 compander. How do
>>>>> I tune the system to address sibiliance???
>>>> Do you hear the problem on ALL program material?
>>> Yes.
>>>
>>>> Wouldn't the maintenance engineer handle this?
>>
>>
>> so if ALL of the audio [emanating] from the station sounds too sibilant
>> it is likely that one of the stages on the way to the transmitter is
>> either being compressed to far and then amplified or there is too much
>> gain. Interrupt the signal and find out where it is happening
>
>
> You really cannot separate the MTS-4 (compander) from the Cadco
> (modulator). ... darned analog components!

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