Archived from groups: alt.comp.periphs.mainboard.asus,alt.computer,alt.computers,microsoft.public.windowsxp.hardware (
More info?)
you could download DSP software for the bass and treble controls
--
Thank You,
Keith R. Lewis
Computers Everywhere!
http://www.computerseverywhere.net
"Paul" <nospam@needed.com> wrote in message
news:nospam-2311042227280001@192.168.1.177...
> In article <3MednbL_37EnBz7cRVn-vQ@comcast.com>, "Ritter197"
> <Ritter197@Comcast.net> wrote:
>
>> I have the ASUS P800 Motherboard and windows xp.
>> This MB has the sound built in but I have found no way to reduce the bass
>> output.
>>
>> I can adjust Balance, Mic input and many other things, but the bass and
>> treble adjustments were greyed out.
>>
>> How can I adjust this bass on my Cambridge speakers with the separate
>> bass
>> reflex speaker?
>
> In the AC97 standard, Bass and Treble are options. In the few
> device datasheets I've looked at, Bass and Treble are not implemented.
> And that is why the Bass and Treble controls are typically greyed
> out. Bass and Treble could be implemented with DSP (digital signal
> processing) or they could be implemented with analog circuits - the
> former adds a fair number of logic gates to the chip, and makes the
> silicon die larger. The latter might mean adding pins to the chip,
> and AC97 chips have a fixed defined set of pins, so making bigger
> chips is not much of an option for the chip makers.
>
> You'll have better luck with a separate sound card, but again beware
> of cheaper products, and read the documentation/reviews carefully, to
> make sure they have the controls you are after. I try to get pictures
> of the control panels now (from review articles on the Internet, as
> the company making the product usually don't give pictures), to prove
> the product has the features I want.
>
> It is funny, how a simple feature like this requires so much
> care when you are shopping, but that is the nature of computing -
> some complicated functions are provided, that you'll never use,
> and some simple things go missing, no matter how much you pay.
>
> There are several ways a function like this can be provided:
>
> 1) Place the function in the AC97 CODEC, as described above. Use
> DSP or old fashioned analog filter circuits.
> 2) Place the function in the Southbridge. The Nforce2 MCP-T
> on the A7N8X Deluxe boards, has DSP functions in it, and I
> believe there is a graphics equalizer function in the mixer.
> 3) Place the function in the audio software path. That requires
> digital signal processing (DSP) software, which modifies the
> spectrum of the signals as the user desires. The P5xxx boards
> that have a Cmedia CODEC on them, have a graphics equalizer that
> uses CPU cycles (as near as I can tell, as there doesn't appear
> to be a DSP in either the Southbridge or in the CODEC chip
> itself).
>
> When it comes to DVD playback, there is an additional issue.
> If the DVD provides ordinary audio signals, these can go through
> the analog path and receive whatever processing the hardware and
> software offer. For example, if you had a board with Azalia audio
> and the Cmedia CODEC, you could use the graphics equalizer to
> change the bass and treble on the DVD playback. The signals could
> come out in analog format in that case.
>
> When the DVD disk has AC3 encoded digital audio information, you
> need a Dolby Labs license to touch the stream of information. That
> is why, I think without exception, AC3 streams are passed
> transparently through the hardware path and out the SPDIF connector.
> Knowing that, any computer speaker maker should have audio shaping
> controls on the speakers themselves, as otherwise the user has no
> way of adjusting things.
>
> Both the Nforce2 MCP-T on the A7N8X Deluxe and the Cmedia software
> for their Azalia CODEC, have a Dolby license to encode AC3. That
> means, when a 5.1 digital stream is available, the MCP-T uses
> its hardware, and the Cmedia CODEC uses its driver software, to
> convert 5.1 digital, into the two channel compressed AC3 format
> that travels out the SPDIF connector. If either of those solutions
> have spectral shaping in front of the encoder, then a user can
> equalize signals as desired. In the Cmedia case, one user has
> already noticed, that the Cmedia software adds a 1.5 second delay
> to the audio path, which in many situations is a disaster.
>
> Really, for all of the complexity, I think an all analog audio
> solution will make you happier than a digital solution. There
> is more room for manipulation of the signal streams, without
> anyone having to pay licensing fees. If the stupid SPDIF
> connector had six channels on it, none of this would be
> necessary. I guess nobody sees any benefit in creating a
> digital audio standard, to bypass the licensing issues.
> (USB2 would probably be fast enough for this, but you really
> want the constant bit rate provided by SPDIF like devices, to
> keep a steady flow of data available to the speakers. USB has
> a bit too much software in the path for my liking.)
>
> To summarize:
> 1) AC97, simple bass and treble optional and seldom done.
> 2) DVD playback via analog path, can be changed in flight
> by whatever functions are in hardware or software.
> 3) DVD playback via AC3 digital option, goes straight out
> the SPDIF connector.
> 4) Motherboards where the audio hardware or software has
> a Dolby digital license for decoding/encoding AC3,
> could potentially do more - but exactly what, I don't
> know. Perhaps an audio or DVD newsgroup has more info
> on such complex issues. Motherboard manuals have little
> to offer on such subjects. Keeping audio/video sync is
> hard to do in such a situation.
>
> HTH,
> Paul