Re: [Alsa-user] Unmolested audio

2008-06-13 Thread Grant
>> On IEEE 32 bit floats the mantissa is 23 bit, so there might be >> situations where you loose the LSB. > > And that was the only point - a "pro audio chain" should be able to > support "digital wire" capability. Any way to test this? - Grant ---

Re: [Alsa-user] Unmolested audio

2008-06-13 Thread Jamie Lokier
Florian Faber wrote: > On Thursday 12 June 2008 20:10:04 Chris Smith wrote: > > On Thursday 12 June 2008, Florian Faber wrote: > > > What makes you think converting a 16 bit unsigned integer to a IEEE > > > 32 bit float and back would change the value? > > Should have used a 24 bit example. I'm of

Re: [Alsa-user] Unmolested audio

2008-06-12 Thread Chris Smith
On Thursday 12 June 2008, Florian Faber wrote: > On IEEE 32 bit floats the mantissa is 23 bit, so there might be > situations where you loose the LSB. And that was the only point - a "pro audio chain" should be able to support "digital wire" capability. > And as long as it doesn't support the sa

Re: [Alsa-user] Unmolested audio

2008-06-12 Thread Florian Faber
On Thursday 12 June 2008 20:10:04 Chris Smith wrote: > On Thursday 12 June 2008, Florian Faber wrote: > > What makes you think converting a 16 bit unsigned integer to a IEEE > > 32 bit float and back would change the value? > Should have used a 24 bit example. I'm of the opinion that with it > the

Re: [Alsa-user] Unmolested audio

2008-06-12 Thread Roman Haefeli
On Thu, 2008-06-12 at 14:10 -0400, Chris Smith wrote: > On Thursday 12 June 2008, Florian Faber wrote: > > What makes you think converting a 16 bit unsigned integer to a IEEE > > 32 bit float and back would change the value? > > Should have used a 24 bit example. I'm of the opinion that with it th

Re: [Alsa-user] Unmolested audio

2008-06-12 Thread Chris Smith
On Thursday 12 June 2008, Florian Faber wrote: > What makes you think converting a 16 bit unsigned integer to a IEEE > 32 bit float and back would change the value? Should have used a 24 bit example. I'm of the opinion that with it the process is not always a bit perfect translation. But I'm open

Re: [Alsa-user] Unmolested audio

2008-06-12 Thread Florian Faber
Chris, > A little peeve with some so called "pro" audio servers is their > inability to act as a 'digital wire', ie: what goes in comes out, > totally unchanged. As an example, there are times you may want the > same exact 16 bits you send out of app to arrive at the audio device > unmolested. Jac

Re: [Alsa-user] Unmolested audio

2008-06-12 Thread Chris Smith
On Monday 09 June 2008, Bill Unruh wrote: > That will at most give you digitization noise which at 16 bit is 96dB > below full signal. Ie, it is much less than the tape hiss from a tape > recorder for example. Not that tape hiss should be a standard we compare everything to :) A little peeve with

Re: [Alsa-user] Unmolested audio

2008-06-10 Thread Grant
>> Is running jack, pulseaudio, or esound enough to jeopordize the bits, >> or must the audio player support the sound server in order for that to >> happen? >> >> - Grant >> >> > > I think you're asking, if the sound server isn't used by the audio player, > will it affect the sound quality? No, i

Re: [Alsa-user] Unmolested audio

2008-06-10 Thread stan
Grant wrote: > Is running jack, pulseaudio, or esound enough to jeopordize the bits, > or must the audio player support the sound server in order for that to > happen? > > - Grant > > I think you're asking, if the sound server isn't used by the audio player, will it affect the sound quality?

Re: [Alsa-user] Unmolested audio

2008-06-10 Thread Grant
>> Thank you for that. It sounds like whether or not these digital >> conversions take place is dependent on the capabilities of the sound >> card or DAC. >> >> > > That and the audio you are playing. If they match, no alsa conversion. >>> >>> I'm not sure about puleaudio, but I think, like jack,

Re: [Alsa-user] Unmolested audio

2008-06-10 Thread Grant
>> Thank you for that. It sounds like whether or not these digital >> conversions take place is dependent on the capabilities of the sound >> card or DAC. >> >> > > That and the audio you are playing. If they match, no alsa conversion. >>> >>> I'm not sure about puleaudio, but I think, like jack,

Re: [Alsa-user] Unmolested audio

2008-06-10 Thread stan
Grant wrote: [snip] > Thank you for that. It sounds like whether or not these digital > conversions take place is dependent on the capabilities of the sound > card or DAC. > > That and the audio you are playing. If they match, no alsa conversion. >> I'm not sure about puleaudio, but I think,

Re: [Alsa-user] Unmolested audio

2008-06-10 Thread Grant
>> I'm kind of an audiophile and I'd like to make sure there is no >> digital alteration being made to my music between the time it is >> decoded from FLAC and passed to the DAC via USB. We could argue about >> whether it makes a difference, but I'd just like to make sure there is >> a straight "p

Re: [Alsa-user] Unmolested audio

2008-06-10 Thread Jamie Lokier
Bill Unruh wrote: > I definitely agree that you want to avoid this . You might look at the > tests I did with the SOX rate conversion routines. Note that if you are > willing to take a long time, that rate conversion can be good. But it takes > a lot of processing and time-- doing a good job in rea

Re: [Alsa-user] Unmolested audio

2008-06-09 Thread Bill Unruh
On Mon, 9 Jun 2008, stan wrote: > Grant wrote: >> I'm kind of an audiophile and I'd like to make sure there is no >> digital alteration being made to my music between the time it is >> decoded from FLAC and passed to the DAC via USB. We could argue about >> whether it makes a difference, but I'd

Re: [Alsa-user] Unmolested audio

2008-06-09 Thread stan
Grant wrote: > I'm kind of an audiophile and I'd like to make sure there is no > digital alteration being made to my music between the time it is > decoded from FLAC and passed to the DAC via USB. We could argue about > whether it makes a difference, but I'd just like to make sure there is > a str

[Alsa-user] Unmolested audio

2008-06-09 Thread Grant
I'm kind of an audiophile and I'd like to make sure there is no digital alteration being made to my music between the time it is decoded from FLAC and passed to the DAC via USB. We could argue about whether it makes a difference, but I'd just like to make sure there is a straight "pass-through" ha