Hi gang!
I'm trying to record (to .wav files) sound coming in on the line input of my sound card (in this case, output of a tape deck).
For LISTENING purposes, I can control the level with the Gnome Mixer.
However, the RECORDING level is not affected by the mixer. As a result, the recorded audio is badly clipped and horribly distorted.
I don't understand enough about how this stuff works to have a clue how to troubleshoot this problem.
Can someone offer helpful advice?
Thanks!
On Saturday 28 April 2007 6:58:47 am fredex wrote:
Hi gang!
I'm trying to record (to .wav files) sound coming in on the line input of my sound card (in this case, output of a tape deck).
For LISTENING purposes, I can control the level with the Gnome Mixer.
However, the RECORDING level is not affected by the mixer. As a result, the recorded audio is badly clipped and horribly distorted.
I don't understand enough about how this stuff works to have a clue how to troubleshoot this problem.
Can someone offer helpful advice?
Dunno about the gnome mixer, but kmix has input and output settings. What are you using to make the recording? Audacity seems to have a slider for input volume.
Sorry I can't be more helpful, my stereo is not connected to my computer at the moment. :(
Tim
On Sat, Apr 28, 2007 at 08:40:56AM -0400, Tim Wunder wrote:
On Saturday 28 April 2007 6:58:47 am fredex wrote:
Hi gang!
I'm trying to record (to .wav files) sound coming in on the line input of my sound card (in this case, output of a tape deck).
For LISTENING purposes, I can control the level with the Gnome Mixer.
However, the RECORDING level is not affected by the mixer. As a result, the recorded audio is badly clipped and horribly distorted.
I don't understand enough about how this stuff works to have a clue how to troubleshoot this problem.
Can someone offer helpful advice?
Dunno about the gnome mixer, but kmix has input and output settings. What are you using to make the recording? Audacity seems to have a slider for input volume.
I've tried Audacity and rec (from the sox package) and ecasound and 2 or 3 other things I've run into while Googling.
I have to admit that yes, Audacity does have a record level slider. And it is the single app I've tried in which I CAN control the record level. But even then, the recorded sound is slightly clipped sounding (though much less bad) when played back.
Note that the sound straight from the tape deck, when fed into the computer and played through the speakers attached to the sound card, is fine (or as close to fine as one can tell given the cheap speakers I have at the moment), but when recorded then played back, even the recording from Audacity is notably degraded.
Recording with Audacity seems sluggish--it updates the display (the waveform display) in clumps rather than smoothly. When played back, in addition to the muddiness/distortion, there are occasional little defects where it sounds as if some samples were lost. I'm guessing that all the graphical stuff going on is making the system sufficiently busy that it loses blobs of data during recording, which is why I was trying non-GUI recording tools. All of them seem to want to record only with the record volume turned all the way up. Viewing any of those recordings in Audacity shows that ALL the sound is clipped, not just little bits of it, as with Audacity's recordings.
I'm running Centos 4.4 on an Athlon XP 2600+ with a gig of RAM, so it should have adequate horsepower. I did do some recording several years ago on a K6-2/350 and didn't have these problems, and this machine has LOTS more ponies under the hood than did that one.
ecasound comes with a tool named "ecasignalview" which shows the number of clipped samples. Since I can't figure out how to adjust the input levels to ecasound, it says basically that all samples are clipped.
I am using the built-in (AC-97) audio hardware, so it's surely not really high-quality stuff, but still, it ought to be possible to do better than I have so far been able to do.
the Gnome mixer allows one to select a given input channel to be the one being recorded, and presumably the slider for that channel is supposed to control the recording level. But in fact all these programs, Audacity included, will record regardless of the setting of the "rec" checkbox, and the slider for the "line" input (which is where the tape deck comes in) controls the audio volume I hear but has no effect on the record level.
I'm wondering if I should change my desktop to KDE and try with its sound tools. I suppose it couldn't harm anything to try.
Suggestions welcome!
Sorry I can't be more helpful, my stereo is not connected to my computer at the moment. :(
Tim
CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
fredex spake the following on 4/28/2007 9:01 AM:
On Sat, Apr 28, 2007 at 08:40:56AM -0400, Tim Wunder wrote:
On Saturday 28 April 2007 6:58:47 am fredex wrote:
Hi gang!
I'm trying to record (to .wav files) sound coming in on the line input of my sound card (in this case, output of a tape deck).
For LISTENING purposes, I can control the level with the Gnome Mixer.
However, the RECORDING level is not affected by the mixer. As a result, the recorded audio is badly clipped and horribly distorted.
I don't understand enough about how this stuff works to have a clue how to troubleshoot this problem.
Can someone offer helpful advice?
Dunno about the gnome mixer, but kmix has input and output settings. What are you using to make the recording? Audacity seems to have a slider for input volume.
I've tried Audacity and rec (from the sox package) and ecasound and 2 or 3 other things I've run into while Googling.
I have to admit that yes, Audacity does have a record level slider. And it is the single app I've tried in which I CAN control the record level. But even then, the recorded sound is slightly clipped sounding (though much less bad) when played back.
Note that the sound straight from the tape deck, when fed into the computer and played through the speakers attached to the sound card, is fine (or as close to fine as one can tell given the cheap speakers I have at the moment), but when recorded then played back, even the recording from Audacity is notably degraded.
Recording with Audacity seems sluggish--it updates the display (the waveform display) in clumps rather than smoothly. When played back, in addition to the muddiness/distortion, there are occasional little defects where it sounds as if some samples were lost. I'm guessing that all the graphical stuff going on is making the system sufficiently busy that it loses blobs of data during recording, which is why I was trying non-GUI recording tools. All of them seem to want to record only with the record volume turned all the way up. Viewing any of those recordings in Audacity shows that ALL the sound is clipped, not just little bits of it, as with Audacity's recordings.
Maybe it is your soundcard. Not all soundcards work 100% with linux. and I think you would have to have DMA working with it to get good recordings. Playing directly and recording to storage take different amounts of processor time. Also, are you recording to a line in port on the card or a mic port. Line in and mic ports have different attenuation and might need a matching transformer or some other sort of level control. That is why higher end cards have both a mic and line in port.
Maybe it is your soundcard. Not all soundcards work 100% with linux. and I think you would have to have DMA working with it to get good recordings. Playing directly and recording to storage take different amounts of processor time. Also, are you recording to a line in port on the card or a mic port. Line in and mic ports have different attenuation and might need a matching transformer or some other sort of level control. That is why higher end cards have both a mic and line in port.
feeding a Line Out to a Mic In just needs attentuator resistors, not a matching transformer. you can buy a mini-stereo-phone to mini-stereo-phone patch cable with these attenuators built in, designed to allow you to feed the line out from a CD player into a walkman style tape deck's mic input. The usual attenuator is 100K ohms in series, and 10k ohms in parallel . Note recording from a Mic Input will likely be noisier.
On Sat, Apr 28, 2007 at 10:34:14AM -0700, John R Pierce wrote:
Maybe it is your soundcard. Not all soundcards work 100% with linux. and I think you would have to have DMA working with it to get good recordings. Playing directly and recording to storage take different amounts of processor time. Also, are you recording to a line in port on the card or a mic port. Line in and mic ports have different attenuation and might need a matching transformer or some other sort of level control. That is why higher end cards have both a mic and line in port.
feeding a Line Out to a Mic In just needs attentuator resistors, not a matching transformer. you can buy a mini-stereo-phone to mini-stereo-phone patch cable with these attenuators built in, designed to allow you to feed the line out from a CD player into a walkman style tape deck's mic input. The usual attenuator is 100K ohms in series, and 10k ohms in parallel . Note recording from a Mic Input will likely be noisier.
It claims to be "line in", not "mic".
fredex wrote:
I'm wondering if I should change my desktop to KDE and try with its sound tools. I suppose it couldn't harm anything to try.
You can use KDE if you want, of course system-wide settings and user-wide settings apply in both. You can also run under GNOME, or even add to the GNOME menus the KDE applications that you like. Also CentOS 5 is far superior to CentOS 4, regarding user apps and tools, so perhaps you may want to give CentOS 5.0 a try, it is very good and *faster*!
What's your sound card BTW? Perhaps you may have some driver problem?
Ioannis Vranos wrote:
fredex wrote:
I'm wondering if I should change my desktop to KDE and try with its sound tools. I suppose it couldn't harm anything to try.
You can use KDE if you want, of course system-wide settings and user-wide settings apply in both. You can also run under GNOME, or even add to the GNOME menus the KDE applications that you like. Also CentOS 5 is far superior to CentOS 4, regarding user apps and tools, so perhaps you may want to give CentOS 5.0 a try, it is very good and *faster*!
What's your sound card BTW? Perhaps you may have some driver problem?
Just saw that you mentioned "am using the built-in (AC-97) audio hardware".
In any case, perhaps you want to try CentOS 5.0, it is far superior in everything!
On Sat, Apr 28, 2007 at 09:02:38PM +0300, Ioannis Vranos wrote:
Ioannis Vranos wrote:
fredex wrote:
I'm wondering if I should change my desktop to KDE and try with its sound tools. I suppose it couldn't harm anything to try.
You can use KDE if you want, of course system-wide settings and user-wide settings apply in both. You can also run under GNOME, or even add to the GNOME menus the KDE applications that you like. Also CentOS 5 is far superior to CentOS 4, regarding user apps and tools, so perhaps you may want to give CentOS 5.0 a try, it is very good and *faster*!
What's your sound card BTW? Perhaps you may have some driver problem?
Just saw that you mentioned "am using the built-in (AC-97) audio hardware".
In any case, perhaps you want to try CentOS 5.0, it is far superior in everything!
Yes, I DO want to try it. But it will take me some time to prepare for the conversion. I want to do a clean install, so planning is required to be able to move over all my crap, mail server settings, etc., etc.
Also thinking of buying a matched pair of SATA drives (newegg has some nice prices on 160 gig WD and Seagate SATA drives) and using Linux's raid capability to do a mirrored pair, when I do go to Centos 5. But that's not going to happen in the immediate future.
-
fredex -
Ioannis Vranos -
John R Pierce -
Scott Silva -
Tim Wunder