Re: Advice to an audiophobe -- If others need it.

2008-12-28 Thread Tim
On Sat, 2008-12-27 at 15:50 -0500, William Case wrote:
> You will notice that the first 11 URL's I cite are for people like me
> who have 'tin ears' and only have a secondary interest in sound as it
> relates to music.  As a side note, all my life I had distinguished
> music as having only three characteristics; loud or soft, high or low;
> and, pleasant or annoying.  It seems that I wasn't as far off the mark
> as I thought I was.  I will, from hereon, try to pick up on and
> understand some of the more basic musical nuances I hear.

Might be worth exploring some other types of music, if you're tone deaf,
you might find something that does appeal.

As well as popular, there's a plethora of genres:  Classical, jazz,
avantgarde, percussion, etc., etc.

-- 
[...@localhost ~]$ uname -r
2.6.27.9-73.fc9.i686

Don't send private replies to my address, the mailbox is ignored.  I
read messages from the public lists.



-- 
fedora-list mailing list
fedora-list@redhat.com
To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
Guidelines: http://fedoraproject.org/wiki/Communicate/MailingListGuidelines


Re: Advice to an audiophobe -- If others need it.

2008-12-27 Thread Russell Miller

William Case wrote:

Hi;

With special thanks to Tim and David, I have read and assembled a list
of audio explanation sites.  Tim and David gave me enough context so
that when I read (or re-read) the information at these sites, things
began to make sense.  I have copied the list of sites I have used for
anyone else who might be as befuddled as I was.  I have tried to put
them into some logical order.
 
I'm a classical musician who obviously also has an interest in this 
subject.  If there's not a separate list for discussion of it, I'd like 
to create one (I run a mailing list server).  But I'm not going to be 
the only member.  Anyone interested?


--Russell

--
fedora-list mailing list
fedora-list@redhat.com
To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
Guidelines: http://fedoraproject.org/wiki/Communicate/MailingListGuidelines


Re: Advice to an audiophobe -- If others need it.

2008-12-27 Thread William Case
Hi;

With special thanks to Tim and David, I have read and assembled a list
of audio explanation sites.  Tim and David gave me enough context so
that when I read (or re-read) the information at these sites, things
began to make sense.  I have copied the list of sites I have used for
anyone else who might be as befuddled as I was.  I have tried to put
them into some logical order.
 
On Tue, 2008-12-23 at 10:55 -0500, William Case wrote:
> Hi;
> 
> I have avoided sound technology most of my life.  I have a 'tin ear' and
> most music just sounds to me like somebody talking in an annoying voice.
> However, recent problems with alsa mixer and/or pulseaudio has convinced
> me that the time has come to spend some time learning the rudiments of
> sound technology.  So ...
> 

> 
> I have googled, searched Wikipedia, read the PulseAudio documentation as
> well as Gnome Help.  It all still leaves me befuddled -- either too
> simple or two technical.  Once I try to throw in the concept of various
> 'codecs' I am lost.
> 
__
Sound (& Music) Creation and Perception

http://en.wikipedia.org/wiki/Auditory_cortex

http://en.wikipedia.org/wiki/Musical_acoustics

http://en.wikipedia.org/wiki/Place_theory

http://en.wikipedia.org/wiki/Temporal_theory

http://en.wikipedia.org/wiki/Volley_theory

http://en.wikipedia.org/wiki/Perception

http://en.wikipedia.org/wiki/Pitch_(music)

http://en.wikipedia.org/wiki/Loudness

http://en.wikipedia.org/wiki/Timbre

http://en.wikipedia.org/wiki/Harmonic

http://en.wikipedia.org/wiki/Rhythmic
___

Computer Sound - Acquiring, transferring, storing, altering and
broadcasting.

http://en.wikipedia.org/wiki/Sound_cards

http://computer.howstuffworks.com/sound-card5.htm

http://www.pctechguide.com/44SoundCards.htm

http://en.wikipedia.org/wiki/ALSA_(Linux)

http://en.wikipedia.org/wiki/PulseAudio

http://en.wikipedia.org/wiki/Codecs

http://en.wikipedia.org/wiki/Open_source_codecs_and_containers

http://en.wikipedia.org/wiki/List_of_codecs

http://en.wikipedia.org/wiki/Ogg

http://en.wikipedia.org/wiki/Vorbis

http://en.wikipedia.org/wiki/GStreamer

http://en.wikipedia.org/wiki/Totem_(media_player)

http://en.wikipedia.org/wiki/Firewire

http://en.wikipedia.org/wiki/List_of_Linux_audio_software

Musical Instrument Digital Interface
http://en.wikipedia.org/wiki/MIDI

On Wikipedia, I recommend checking "See also", "References" and
"External Links" at the bottom of each page to find further and deeper
explanations.

The main breakthrough for me was being shown that ALSA was a driver for
the sound card (chip) hardware, while PulseAudio was a server program,
in much the same way that 'ati' or 'nv' are video card drivers and X
windows is a window graphics server.

All other sound programs, codecs etc. are, at heart, just libraries used
by either ALSA or PulseAudio.

It is best to take a look at http://en.wikipedia.org/wiki/PulseAudio
flowchart a few screens down as recommended by David Timms just to get a
visual road map before starting in reading.

You will notice that the first 11 URL's I cite are for people like me
who have 'tin ears' and only have a secondary interest in sound as it
relates to music.  As a side note, all my life I had distinguished music
as having only three characteristics; loud or soft, high or low; and,
pleasant or annoying.  It seems that I wasn't as far off the mark as I
thought I was.  I will, from hereon, try to pick up on and understand
some of the more basic musical nuances I hear.

Thanks all.

-- 
Regards Bill
Fedora 10, Gnome 2.24.2
Evo.2.24.2, Emacs 22.2.1

-- 
fedora-list mailing list
fedora-list@redhat.com
To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
Guidelines: http://fedoraproject.org/wiki/Communicate/MailingListGuidelines


Re: Advice to an audiophobe ??

2008-12-25 Thread David Timms

William Case wrote:

David, Thank you;

If you cut and pasted these answers, I would love to know where (or what
site) you got them.  If you took the time to write them off the top of
your head, I doubly thank you. You have given me enough information to
do some proper research of my own particular questions and do a small
write up for my own use.
Unfortunately the background digital audio theory comes straight from my 
electronics and communication engineering degree course (15 years ago), 
but I guess became "common knowledge" to me due to interest and 
continued usage, both for at home and work (where we use audio DSP black 
boxes to save on needing to supply separate audio mixers, equalizers, 
volume controls, and audio routing boxes to client jobs). If you are 
into guitar, you might like to try a program like rakarrack. This 
provides audio processing functionality similar to what those DSP boxes 
can do, without the expense; but it does require a pretty decent CPU, 
and an understanding of the jack audio connection kit.


While I was expanding on Tim's answer's, I found myself starting to 
spout technical terms; I just backpedalled each time and tried to find 
non-technical words to describe the way things are.


In terms of audio apps in fedora, my summarizing way over-simplifies 
things, but hopefully it gives a good idea of the makeup of the system. 
( http://www.linux.com/feature/119926

http://en.wikipedia.org/wiki/PulseAudio flowchart a few screens down
http://0pointer.de/blog/projects/guide-to-sound-apis.html for a what 
sound system fits best where)


Thanks for the complement, David T.

--
fedora-list mailing list
fedora-list@redhat.com
To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
Guidelines: http://fedoraproject.org/wiki/Communicate/MailingListGuidelines


Re: Advice to an audiophobe ??

2008-12-25 Thread Les

On Fri, 2008-12-26 at 01:04 +1100, David Timms wrote:
> William Case wrote:
> > On Wed, 2008-12-24 at 08:30 +1030, Tim wrote:
> >> On Tue, 2008-12-23 at 10:55 -0500, William Case wrote:
> ...
> > 1. Gives me a whole range of adjustments for different channels.  (I
> > assume channels means different sources  e.g. Master, Headphone, PCM etc.).
> Just to clarify, a source device generates an audio signal( line in, PCM 
> (pulse code modulation = wav uncompressed audio), that might then get 
> processed (eg volume control, master, headphone), and then sent to a 
> destination (often an output device like a speaker connector or 
> headphone jack).
> 
> Because a typical soundcard has an internal hardware mixer, it can 
> usually mix together various inputs (sources) like CD input, mic input 
> and recorded audio signals, and produce a single output signal (mostly 
> in stereo=2 channels). When mixing together externally received signals, 
> no main CPU processing power is used, unless you are trying to record to 
> hard disk etc.
> 
> > 2. gives me two choices and 
> > 3., 4., 5. gives me only Master.  
> > Which should I choose and why?
> capture means recording - usually from a line in (eg from a vcr or mp3 
> player etc), or from a microphone. So exclude those from your choice.
> 
> > If I should be using HDA NVida (Alsa-mixer), why do I have PulseAudio
> > options?
> Consider pulse audio to be a real-time digital mixer and volume control, 
> where the audio calculations are performed inside your main CPU. In the 
> default setup, once pulseaudio has done it's processing, it passes the 
> result to the alsa driver which outputs the audio data to the soundcard. 
> The soundcard turns the digital audio data into analog audio signals for 
>   use with amplifier, speakers, or headphones.
> 
> Pulseaudio also has enhanced capabilities like remembering that when you 
> playback with xmms that you like to output via your amplifiers and 
> speakers, but when you are viewing a flash video, to playback into your 
> headphones instead, at a different level. Another capability let's you 
> choose the destination playback device while the material is actually 
> being played. A third capability let's the output go to an audio device 
> on another machine. Obviously, this is a bit trickier to set up.
> 
> ...
> >> These individual mixer input controls should normally be left off if you
> >> never use them, as they can each introduce noise (hiss, beeps and
> >> burbles, etc.) to the system.  
> > I will turn them off except for Master and Front.  I will experiment
> > with PC Speaker.  Of course these are only available to me if I use the
> > default alsa mixer setting.
> It's not a one or other setting, both parts will still be involved; 
> pulseaudio will process, mix, and attenuate sound signals, whereas alsa 
> will drive the physical hardware. The setting you are seeing lets you 
> decide whether to control the physical driver volume levels or the 
> software generated pulseaudio volume controls. If you mute or turn the 
> alsa master way down, it wont matter how high you turn the pulseaudio 
> mixer, since the alsamixer comes after the pulseaudio one in the audio 
> chain. (also true for the reverse).
> 
> If you play back a loud audio file, and turn both the pulseaudio source 
>   and master up full. Then change to the alsa setting. You can then use 
> the also setting to set up an absolute maximum level that you would want 
> to hear, by adjusting the master. Then you could go back to the 
> pulseaudio setting to adjust the playback to a comfortable setting, and 
> from then on only use the pulseaudio setting.
> 
> ...
> >>>   * How is sound related to video ?
> > 
> >> Sound is the sound, video is the picture...  The question is too vague
> >> to be answerable.
> In digital format, sound and vision are both represented with digital 
> 1's and 0's. With all video and audio file types, there is a packing 
> together of the audio and video information into the one file. The 
> multiplexed file provides information about when to playback each frame 
> of video in relation to the audio in the file. For example, an mpeg2 
> (dvd) file might have two frames of video, then 2 of audio, then 1 of 
> video, two audio in an order to achieve a consistent throughput of audio 
> and video data.
> 
> >>>   * Why are there so many files associated with producing sound?
> In digital audio, the most basic file type is waveform (.wav), where 
> each momentary value of audio is stored, on a 1 for 1 basis. Experiments 
> and calculations can show us that for something we store as quality 
> musical recording we need to sample that momentary value at 44kHz (times 
> per second) or higher so as not to disrupt our digital recording with 
> audio aliases. Since we also seem to enjoy the spatial enhancement 
> produced by stereo or more channels, the file needs to store both left 
> and right information. Finally, we found that if

Re: Advice to an audiophobe ??

2008-12-25 Thread William Case
David, Thank you;

If you cut and pasted these answers, I would love to know where (or what
site) you got them.  If you took the time to write them off the top of
your head, I doubly thank you. You have given me enough information to
do some proper research of my own particular questions and do a small
write up for my own use.

Ps.  I am top posting because there is no other place to appropriately
express my thanks.

On Fri, 2008-12-26 at 01:04 +1100, David Timms wrote:
> William Case wrote:
> > On Wed, 2008-12-24 at 08:30 +1030, Tim wrote:
> >> On Tue, 2008-12-23 at 10:55 -0500, William Case wrote:
> ...
> > 1. Gives me a whole range of adjustments for different channels.  (I
> > assume channels means different sources  e.g. Master, Headphone, PCM etc.).
> Just to clarify, a source device generates an audio signal( line in, PCM 
> (pulse code modulation = wav uncompressed audio), that might then get 
> processed (eg volume control, master, headphone), and then sent to a 
> destination (often an output device like a speaker connector or 
> headphone jack).
> 
> Because a typical soundcard has an internal hardware mixer, it can 
> usually mix together various inputs (sources) like CD input, mic input 
> and recorded audio signals, and produce a single output signal (mostly 
> in stereo=2 channels). When mixing together externally received signals, 
> no main CPU processing power is used, unless you are trying to record to 
> hard disk etc.
> 
> > 2. gives me two choices and 
> > 3., 4., 5. gives me only Master.  
> > Which should I choose and why?
> capture means recording - usually from a line in (eg from a vcr or mp3 
> player etc), or from a microphone. So exclude those from your choice.
> 
> > If I should be using HDA NVida (Alsa-mixer), why do I have PulseAudio
> > options?
> Consider pulse audio to be a real-time digital mixer and volume control, 
> where the audio calculations are performed inside your main CPU. In the 
> default setup, once pulseaudio has done it's processing, it passes the 
> result to the alsa driver which outputs the audio data to the soundcard. 
> The soundcard turns the digital audio data into analog audio signals for 
>   use with amplifier, speakers, or headphones.
> 
> Pulseaudio also has enhanced capabilities like remembering that when you 
> playback with xmms that you like to output via your amplifiers and 
> speakers, but when you are viewing a flash video, to playback into your 
> headphones instead, at a different level. Another capability let's you 
> choose the destination playback device while the material is actually 
> being played. A third capability let's the output go to an audio device 
> on another machine. Obviously, this is a bit trickier to set up.
> 
> ...
> >> These individual mixer input controls should normally be left off if you
> >> never use them, as they can each introduce noise (hiss, beeps and
> >> burbles, etc.) to the system.  
> > I will turn them off except for Master and Front.  I will experiment
> > with PC Speaker.  Of course these are only available to me if I use the
> > default alsa mixer setting.
> It's not a one or other setting, both parts will still be involved; 
> pulseaudio will process, mix, and attenuate sound signals, whereas alsa 
> will drive the physical hardware. The setting you are seeing lets you 
> decide whether to control the physical driver volume levels or the 
> software generated pulseaudio volume controls. If you mute or turn the 
> alsa master way down, it wont matter how high you turn the pulseaudio 
> mixer, since the alsamixer comes after the pulseaudio one in the audio 
> chain. (also true for the reverse).
> 
> If you play back a loud audio file, and turn both the pulseaudio source 
>   and master up full. Then change to the alsa setting. You can then use 
> the also setting to set up an absolute maximum level that you would want 
> to hear, by adjusting the master. Then you could go back to the 
> pulseaudio setting to adjust the playback to a comfortable setting, and 
> from then on only use the pulseaudio setting.
> 
> ...
> >>>   * How is sound related to video ?
> > 
> >> Sound is the sound, video is the picture...  The question is too vague
> >> to be answerable.
> In digital format, sound and vision are both represented with digital 
> 1's and 0's. With all video and audio file types, there is a packing 
> together of the audio and video information into the one file. The 
> multiplexed file provides information about when to playback each frame 
> of video in relation to the audio in the file. For example, an mpeg2 
> (dvd) file might have two frames of video, then 2 of audio, then 1 of 
> video, two audio in an order to achieve a consistent throughput of audio 
> and video data.
> 
> >>>   * Why are there so many files associated with producing sound?
> In digital audio, the most basic file type is waveform (.wav), where 
> each momentary value of audio is stored, on a 1 for 1 basis. Experim

Re: Advice to an audiophobe ??

2008-12-25 Thread David Timms

William Case wrote:

On Wed, 2008-12-24 at 08:30 +1030, Tim wrote:

On Tue, 2008-12-23 at 10:55 -0500, William Case wrote:

...

1. Gives me a whole range of adjustments for different channels.  (I
assume channels means different sources  e.g. Master, Headphone, PCM etc.).
Just to clarify, a source device generates an audio signal( line in, PCM 
(pulse code modulation = wav uncompressed audio), that might then get 
processed (eg volume control, master, headphone), and then sent to a 
destination (often an output device like a speaker connector or 
headphone jack).


Because a typical soundcard has an internal hardware mixer, it can 
usually mix together various inputs (sources) like CD input, mic input 
and recorded audio signals, and produce a single output signal (mostly 
in stereo=2 channels). When mixing together externally received signals, 
no main CPU processing power is used, unless you are trying to record to 
hard disk etc.


2. gives me two choices and 
3., 4., 5. gives me only Master.  
Which should I choose and why?
capture means recording - usually from a line in (eg from a vcr or mp3 
player etc), or from a microphone. So exclude those from your choice.



If I should be using HDA NVida (Alsa-mixer), why do I have PulseAudio
options?
Consider pulse audio to be a real-time digital mixer and volume control, 
where the audio calculations are performed inside your main CPU. In the 
default setup, once pulseaudio has done it's processing, it passes the 
result to the alsa driver which outputs the audio data to the soundcard. 
The soundcard turns the digital audio data into analog audio signals for 
 use with amplifier, speakers, or headphones.


Pulseaudio also has enhanced capabilities like remembering that when you 
playback with xmms that you like to output via your amplifiers and 
speakers, but when you are viewing a flash video, to playback into your 
headphones instead, at a different level. Another capability let's you 
choose the destination playback device while the material is actually 
being played. A third capability let's the output go to an audio device 
on another machine. Obviously, this is a bit trickier to set up.


...

These individual mixer input controls should normally be left off if you
never use them, as they can each introduce noise (hiss, beeps and
burbles, etc.) to the system.  

I will turn them off except for Master and Front.  I will experiment
with PC Speaker.  Of course these are only available to me if I use the
default alsa mixer setting.
It's not a one or other setting, both parts will still be involved; 
pulseaudio will process, mix, and attenuate sound signals, whereas alsa 
will drive the physical hardware. The setting you are seeing lets you 
decide whether to control the physical driver volume levels or the 
software generated pulseaudio volume controls. If you mute or turn the 
alsa master way down, it wont matter how high you turn the pulseaudio 
mixer, since the alsamixer comes after the pulseaudio one in the audio 
chain. (also true for the reverse).


If you play back a loud audio file, and turn both the pulseaudio source 
 and master up full. Then change to the alsa setting. You can then use 
the also setting to set up an absolute maximum level that you would want 
to hear, by adjusting the master. Then you could go back to the 
pulseaudio setting to adjust the playback to a comfortable setting, and 
from then on only use the pulseaudio setting.


...

  * How is sound related to video ?



Sound is the sound, video is the picture...  The question is too vague
to be answerable.
In digital format, sound and vision are both represented with digital 
1's and 0's. With all video and audio file types, there is a packing 
together of the audio and video information into the one file. The 
multiplexed file provides information about when to playback each frame 
of video in relation to the audio in the file. For example, an mpeg2 
(dvd) file might have two frames of video, then 2 of audio, then 1 of 
video, two audio in an order to achieve a consistent throughput of audio 
and video data.



  * Why are there so many files associated with producing sound?
In digital audio, the most basic file type is waveform (.wav), where 
each momentary value of audio is stored, on a 1 for 1 basis. Experiments 
and calculations can show us that for something we store as quality 
musical recording we need to sample that momentary value at 44kHz (times 
per second) or higher so as not to disrupt our digital recording with 
audio aliases. Since we also seem to enjoy the spatial enhancement 
produced by stereo or more channels, the file needs to store both left 
and right information. Finally, we found that if we only store the 
digital value using a small no of bits per sample, when played back we 
hear a harsh, chunky sound, rather than the CD like quality of using 16 
(or more) bits per sample. The catch with all that is it takes up a lot 
space.


To solve space i

Re: Advice to an audiophobe ??

2008-12-24 Thread William Case
Thanks Tim;

Some of these questions were meant simply as examples of the kind of
thing I don't understand.  Nonetheless, to flesh them out:
On Wed, 2008-12-24 at 08:30 +1030, Tim wrote:
> On Tue, 2008-12-23 at 10:55 -0500, William Case wrote:
> >   * What is the difference between alsa and pulseaudio?
> 
> Major differences:  Pulseaudio can produce different sounds at the same
> time (e.g. your IM program can bleep at you while your music program
> carries on playing music, and do so without crashes, hangs, hold-ups for
> one to finish, or nasty noises), and with individual volume controls for
> each (e.g. your IM bleeps subdued, while your music may be reasonably
> loud).
> 
That begs the question, when I use the volume control gui the Device:
field gives me five options:
 1. HDA NVida (Alsa-mixer)
 2. Analog Devices AD1986A (OSS Mixer)
 3. Playback: HDA Nvida - AD198X Analog (PulseAudio Mixer)
 4. Capture: Monitor of HDA NVidia - AD198x (PulseAudio Mixer)
 5. Capture: HDA NVidia - AD198x Analog (PulseAudio Mixer)

HDA NVida (Alsa-mixer) seems to be the default.  

1. Gives me a whole range of adjustments for different channels.  (I
assume channels means different sources e.g. Master, Headphone, PCM
etc.). 
2. gives me two choices and 
3., 4., 5. gives me only Master.  
Which should I choose and why?

Help is less than useless.  There should be a man page but damned if I
can find anything helpful.  man pulseaudio has techish for installing
and setting up the backend but nothing that might be useful to an audio
newbie.

In case it helps:
]$ lspci returns 00:10.1 Audio device: nVidia Corporation MCP51 High
Definition Audio (rev a2) on a ASUS M2NPV-VM motherboard; Fedora 10,
Linux kernel  2.6.27.7-134.fc10.x86_64.

If I should be using HDA NVida (Alsa-mixer), why do I have PulseAudio
options?

> >   * What is the difference between Master, PCM, Front, Line-in, CD,
> > PC-Speaker etc. ?
> 
> Master is the overall volume control over everything, the same control
> that you're used to on your stereo system.
> 
> PCM is just the volume control for generated sounds (Waves, MP3s, etc.).
> 
> Front is the volume control for the front speakers, if you have a system
> with front and rear speakers (3 - 5, or more, speaker systems).  Used as
> a balance control between front versus rear sound levels.
> 
> Line-in will control the volume from the analogue audio line-in in
> socket (which may accept signals from something like 0.2 to 2 volts of
> audio, compare that to microphone sockets, which may use something in
> the range of 0.0001 to 0.010 volts, i.e. there's a large factor of
> difference between line and microphone signal levels).
> 
> CD will (generally) control the volume from the (3 or 4 pin) analogue
> audio cable between the CD/DVD drive and the sound card.  Although it's
> *possible* that systems digitally decoding the audio stream from the
> data from the drive (down the IDE/SATA cable) may *also* pay attention
> to that volume control, it's generally a hardware control of the line
> input on the audio card.
> 
> PC speaker controls, if it's connected, the motherboard beeper volume
> through the sound card.  On some systems, that's a cable between the
> beeper output and a sound card input, on others its handled without
> additional cabling, and others it can't be done.
> 
> These individual mixer input controls should normally be left off if you
> never use them, as they can each introduce noise (hiss, beeps and
> burbles, etc.) to the system.  

I will turn them off except for Master and Front.  I will experiment
with PC Speaker.  Of course these are only available to me if I use the
default alsa mixer setting.

By the way, I have a Multimedia Systems Selector frontend which gives
various perms and combs which don't make sense given the above remarks
and which 'help' says to leave alone if you are not an advanced user
which, obviously, I am not.  The test beep seems to work on just about
any combination.

There is also a sound preferences gui that is set to autodetect that
seems to also test out with any setting giving a long bp.

It is all very confusing.

> And when you do use them, it's dependent
> on the card whether the nominal position for the level control is all
> the way up (for simplicity's sake), or part way up (allowing you to
> listen to signals that are really too low in level).  And again, there's
> variances as to where the partial position may be (e.g. half way, or
> three quarters up).  Also, what's connected to the mixer plays a role
> there, whether it has a low output level that will need boosting, the
> same level as the card expects, or a high level that will normally be
> too much.
> 
> >   * How is sound related to video ?

> Sound is the sound, video is the picture...  The question is too vague
> to be answerable.
> 
Sorry, I didn't mean to be vague.  Most of my sound problems over the
years seem to have been related to sound that goe

Re: Advice to an audiophobe ??

2008-12-23 Thread Tim
On Tue, 2008-12-23 at 10:55 -0500, William Case wrote:
>   * What is the difference between alsa and pulseaudio?

Major differences:  Pulseaudio can produce different sounds at the same
time (e.g. your IM program can bleep at you while your music program
carries on playing music, and do so without crashes, hangs, hold-ups for
one to finish, or nasty noises), and with individual volume controls for
each (e.g. your IM bleeps subdued, while your music may be reasonably
loud).

>   * What is the difference between Master, PCM, Front, Line-in, CD,
> PC-Speaker etc. ?

Master is the overall volume control over everything, the same control
that you're used to on your stereo system.

PCM is just the volume control for generated sounds (Waves, MP3s, etc.).

Front is the volume control for the front speakers, if you have a system
with front and rear speakers (3 - 5, or more, speaker systems).  Used as
a balance control between front versus rear sound levels.

Line-in will control the volume from the analogue audio line-in in
socket (which may accept signals from something like 0.2 to 2 volts of
audio, compare that to microphone sockets, which may use something in
the range of 0.0001 to 0.010 volts, i.e. there's a large factor of
difference between line and microphone signal levels).

CD will (generally) control the volume from the (3 or 4 pin) analogue
audio cable between the CD/DVD drive and the sound card.  Although it's
*possible* that systems digitally decoding the audio stream from the
data from the drive (down the IDE/SATA cable) may *also* pay attention
to that volume control, it's generally a hardware control of the line
input on the audio card.

PC speaker controls, if it's connected, the motherboard beeper volume
through the sound card.  On some systems, that's a cable between the
beeper output and a sound card input, on others its handled without
additional cabling, and others it can't be done.

These individual mixer input controls should normally be left off if you
never use them, as they can each introduce noise (hiss, beeps and
burbles, etc.) to the system.  And when you do use them, it's dependent
on the card whether the nominal position for the level control is all
the way up (for simplicity's sake), or part way up (allowing you to
listen to signals that are really too low in level).  And again, there's
variances as to where the partial position may be (e.g. half way, or
three quarters up).  Also, what's connected to the mixer plays a role
there, whether it has a low output level that will need boosting, the
same level as the card expects, or a high level that will normally be
too much.

>   * How is sound related to video ?

Sound is the sound, video is the picture...  The question is too vague
to be answerable.

>   * Why are there so many files associated with producing sound?

Driver-wise, there's a plethora of different sound cards, which all work
very differently, and each have differing controls available to the
user.  There's a plethora of different audio codecs.  For playing MIDI
files, something needs to generate the actual sounds each note will play
(that could be one file per sound, or you could make use of hardware
that does it).

That's another almost unanswerable question.

-- 
[...@localhost ~]$ uname -r
2.6.27.7-53.fc9.i686

Don't send private replies to my address, the mailbox is ignored.  I
read messages from the public lists.



-- 
fedora-list mailing list
fedora-list@redhat.com
To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
Guidelines: http://fedoraproject.org/wiki/Communicate/MailingListGuidelines


Advice to an audiophobe ??

2008-12-23 Thread William Case
Hi;

I have avoided sound technology most of my life.  I have a 'tin ear' and
most music just sounds to me like somebody talking in an annoying voice.
However, recent problems with alsa mixer and/or pulseaudio has convinced
me that the time has come to spend some time learning the rudiments of
sound technology.  So ...

Can someone recommend a site or manual that explains things like: 
  * What is the difference between alsa and pulseaudio?
  * Which should I choose for the Device: field?
  * What is the difference between Master, PCM, Front, Line-in, CD,
PC-Speaker etc. ?
  * How is sound related to video ?
  * Why are there so many files associated with producing sound?
  * Etc., etc., etc.? ?

I have googled, searched Wikipedia, read the PulseAudio documentation as
well as Gnome Help.  It all still leaves me befuddled -- either too
simple or two technical.  Once I try to throw in the concept of various
'codecs' I am lost.

I am not asking for a personal explanation of the above questions (I
have a bunch more) but all learning suggestions gratefully received.


-- 
Regards Bill
Fedora 10, Gnome 2.24.2
Evo.2.24.2, Emacs 22.2.1

-- 
fedora-list mailing list
fedora-list@redhat.com
To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
Guidelines: http://fedoraproject.org/wiki/Communicate/MailingListGuidelines