correct DC offset or uneven audio

In article <Xns9AA24E26FE600nobody@199.45.49.11>, pb <[email protected]> wrote:
>I corrected the DC offset so the base line is centered, but I can't really
>hear the difference. Because the original baseline moved toward the
>bottom, the bottom part was much shorter than the part above the baseline.
>With that, you can't normalize it further. The volume is low since the
>upper side is over the edge. How can the audio like this be further
>enhanced?

You can't hear DC offset, no. There's really nothing wrong with having
DC offset on a digital file, other than it's using a little bit of your
headroom that you could otherwise use for signal.

It sounds to me like you have a signal that is asymmetric to begin with,
maybe because it was clipped when it was recorded?

>I also found some recorded audio without DC offset problem but has a
>little bit difference in length below and above the baseline. Is it
>normal? What does it tell about the recording device?

Nothing about the recording device, just about the sound source. Vocals
are asymmetric. Triangles aren't asymmetric. Bass drums are very asymmetric.
Flutes aren't asymmetric.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

> Vocals are asymmetric. Triangles aren't asymmetric. Bass drums are very
> asymmetric.
> Flutes aren't asymmetric.

And trombones are the most asymmetrical...
F.

Federico <[email protected]> wrote:
>
>> Vocals are asymmetric. Triangles aren't asymmetric. Bass drums are very
>> asymmetric.
>> Flutes aren't asymmetric.
>
>And trombones are the most asymmetrical...

Trumpets too... as much as 30 dB difference between the top and bottom of
the waveform. Really weird the first time you look at it.

This is why using aggressive limiting on trombones is so effective, but it
also makes them a lot less blatty-sounding.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

But... why are there asymmetrical waveforms?
F.

Federico <[email protected]> wrote:
>But... why are there asymmetrical waveforms?

In the case of the trombone, it's because of the player's lips.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

> In the case of the trombone, it's because of the player's lips.
> --scott

Are you saying that the lips are asymmetrical???:-)
F.

On May 19, 2:40 pm, "Federico" <[email protected]> wrote:
> > In the case of the trombone, it's because of the player's lips.
> > --scott
>
> Are you saying that the lips are asymmetrical???:-)

There is a DC component to the original sound source, because the
air being blown through the horn is moving in (mostly) one direction.
That component is filtered out of the sound as it leaves the bell and
enters open air, but the effect on the sound remains.

rd

On Mon, 19 May 2008 15:45:23 -0700, RD Jones wrote:

> There is a DC component to the original sound source

There is, in the sense you mean, but that's not the reason for an
asymmetrical waveform.

The sound is produced by the lips (or the reed in any reed instrument)
snapping open and shut, and asymmetry results whenever the open period
and shut period aren't the same, and of course there's no reason why they
should be the same.

--
Anahata
[email protected] ==//== 01638 720444
http://www.treewind.co.uk ==//== http://www.myspace.com/maryanahata

Federico wrote:
>> In the case of the trombone, it's because of the player's lips.
>> --scott
>
> Are you saying that the lips are asymmetrical???:-)
> F.

That's why Mick Jagger is so goo with his trombone !


geoff

A trombone player friend of mine is worried 'cause the other instruments
have a "normal" waveform.
He thinks that there are problems with his sound.
F.

Federico <[email protected]> wrote:
>A trombone player friend of mine is worried 'cause the other instruments
>have a "normal" waveform.
>He thinks that there are problems with his sound.
>F.

So, he should try playing the sax instead. Women dig sax players.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Scott Dorsey wrote:

> So, he should try playing the sax instead. Women dig sax players.

Flute is pretty symmetrical, but it will get you more gay guys than
women. Maybe he should get a guitar and learn to yodel. That's a good
chick magnet.


--
If you e-mail me and it bounces, use your secret decoder ring and reach
me here:
double-m-eleven-double-zero at yahoo -- I'm really Mike Rivers
([email protected])

"Scott Dorsey" <[email protected]> wrote in message
news:g0si36$3mn$1@panix2.panix.com...
> Federico <[email protected]> wrote:
>>A trombone player friend of mine is worried 'cause the other instruments
>>have a "normal" waveform.
>>He thinks that there are problems with his sound.
>>F.
>
> So, he should try playing the sax instead. Women dig sax players.
> --scott
> --
> "C'est un Nagra. C'est suisse, et tres, tres precis."

Not necessarily, I played sax in a band and the girls in the audience were
all hot for the drummer.

Go figure.

malachi

malachi wrote:
> "Scott Dorsey" <[email protected]> wrote in message
> news:g0si36$3mn$1@panix2.panix.com...
>> Federico <[email protected]> wrote:
>>> A trombone player friend of mine is worried 'cause the other instruments
>>> have a "normal" waveform.
>>> He thinks that there are problems with his sound.
>>> F.
>> So, he should try playing the sax instead. Women dig sax players.
>> --scott
>> --
>> "C'est un Nagra. C'est suisse, et tres, tres precis."
>
> Not necessarily, I played sax in a band and the girls in the audience were
> all hot for the drummer.
>
> Go figure.
>
> malachi
>
>
Obviously they had something against musicians....

jak (ducks)

"jakdedert" <[email protected]> wrote in message
news:w9qYj.157689$Er2.138192@bignews6.bellsouth.net...
> malachi wrote:
>> "Scott Dorsey" <[email protected]> wrote in message
>> news:g0si36$3mn$1@panix2.panix.com...
>>> Federico <[email protected]> wrote:
>>>> A trombone player friend of mine is worried 'cause the other
>>>> instruments
>>>> have a "normal" waveform.
>>>> He thinks that there are problems with his sound.
>>>> F.
>>> So, he should try playing the sax instead. Women dig sax players.
>>> --scott
>>> --
>>> "C'est un Nagra. C'est suisse, et tres, tres precis."
>>
>> Not necessarily, I played sax in a band and the girls in the audience
>> were all hot for the drummer.
>>
>> Go figure.
>>
>> malachi
> Obviously they had something against musicians....
>
> jak (ducks)

LOL