Re: the aucat recording studio - stereo panning
On Fri, Feb 10, 2012 at 12:05:36AM +0100, Alexandre H wrote: You'll face other problems preventing you from doing everything with aucat. First, there's no reverb, which is necessary to create the spacial feel, volume changes are too abrupt (cause small clicks) and not real-time. Implementing pan, effects and smooth parameter changes would bloat aucat/sndiod. IMO the way to go is to handle processing in small programs (with a simple record-process-play loop) and keep sndiod only for routing the signal to the hardware or other programs. Currently that's the way I handle some effects, I write small programs that apply effects on the record stream to send the result in real-time on the play stream. Then I use -mmon to record the result in a file. Not very flexible, but good enough to test the concept. If I understand what you are doing, perhaps you have another way. Noatun doesn't make the deal ? afaics noatun can't apply effects in real-time and is not very lightweight. When I wrote it can apply effects in real-time I meant this : I play an audio file. While it plays it I can do the following : I go to the menu Settings and select Effects. I add the effect Arts::Synth_FREEVERB for example. I hear the audio changing immediatly as expected. If I change the value of a parameter the audio change immediatly as expected. I can change the position of the playing-cursor without audible delay. It's interactive and the audible audio quality doesn't change (assuming the activity of other parts of the system doesn't change sufficiently). AFAICS the effect is applied online. Noatun and Kaffeine can do this real-time. Sure, this interactive mode has some drawbacks and adding the audio output recording in a new file will slowdown more or less the whole process and perhaps decrease the audible audio quality (and if too many process eat the CPU the real-time will end). At least for this last reason it's certainly better to use batch mode (1 process offline) with a command (sox for example) launched from a CLI. The interactive mode has an obvious advantage : instead of launching many times the same command with differents values in order to find the best values, it's certainly easier to use a player with this real-time capability. This interactive mode is useful not only for listening music or playing with effects but also for discovering, experimenting and testing filters (and GUI isn't mandatory, it can be done in console mode with a keyboard only). This is why I proposed Noatun (it should exists ligtherweight player with this capability). I would like to go further on this point, I will stay brief : An audio editor can use this 2 modes. The user searchs the best values in interactive mode (without recording) and when he pushs the Save button, the editor launch in background something like sox with this values, wich converts the input file and give the output file (batch mode). The editor has the advantages of this 2 modes without their drawbacks. If someone want to develop a new audio filtering editor he can implement this principle on any player with this real-time capability instead of developing a new one from scratch. Noatun seems to be a good candidat. The player with the UI is already done and it works well, so less work to do.
Re: the aucat recording studio - stereo panning
On Feb 09 18:30:01, Geoff Steckel wrote: On 02/09/2012 06:05 PM, Alexandre H wrote: You'll face other problems preventing you from doing everything with aucat. First, there's no reverb, which is necessary to create the spacial feel, volume changes are too abrupt (cause small clicks) and not real-time. Implementing pan, effects and smooth parameter changes would bloat aucat/sndiod. IMO the way to go is to handle processing in small programs (with a simple record-process-play loop) and keep sndiod only for routing the signal to the hardware or other programs. Currently that's the way I handle some effects, I write small programs that apply effects on the record stream to send the result in real-time on the play stream. Then I use -mmon to record the result in a file. Not very flexible, but good enough to test the concept. If I understand what you are doing, perhaps you have another way. Noatun doesn't make the deal ? You play audio file with it and add the filter Arts::Synth_FREEVERB. It has the essential control knobs for reverb. Kaffeine has other filters for audio. Noatun Kaffeine work well with filters, parameters can be adjusted in real-time. And it should be possible to record the audio output in a file. And perhaps you will want to write new filters for them ;). Has 'sox' been mentioned in this context? For many simple filters, source-sox-aucat works well for me. Command line only. Yes, I'd very much like to stay on the command line for this. Would you please care to share the specifics of how you do it? Thank you very much Jan
Re: the aucat recording studio - stereo panning
On Fri, Feb 10, 2012 at 12:05:36AM +0100, Alexandre H wrote: You'll face other problems preventing you from doing everything with aucat. First, there's no reverb, which is necessary to create the spacial feel, volume changes are too abrupt (cause small clicks) and not real-time. Implementing pan, effects and smooth parameter changes would bloat aucat/sndiod. IMO the way to go is to handle processing in small programs (with a simple record-process-play loop) and keep sndiod only for routing the signal to the hardware or other programs. Currently that's the way I handle some effects, I write small programs that apply effects on the record stream to send the result in real-time on the play stream. Then I use -mmon to record the result in a file. Not very flexible, but good enough to test the concept. If I understand what you are doing, perhaps you have another way. Noatun doesn't make the deal ? afaics noatun can't apply effects in real-time and is not very lightweight. -- Alexandre
Re: the aucat recording studio - stereo panning
On 02/10/2012 05:04 AM, Jan Stary wrote: On Feb 09 18:30:01, Geoff Steckel wrote: Has 'sox' been mentioned in this context? For many simple filters, source-sox-aucat works well for me. Command line only. Yes, I'd very much like to stay on the command line for this. Would you please care to share the specifics of how you do it? Thank you very much Jan Check sox.sourceforge.net - the documentation there is good. Geoff
Re: the aucat recording studio - stereo panning
On Feb 10 20:22:21, Geoff Steckel wrote: On 02/10/2012 05:04 AM, Jan Stary wrote: On Feb 09 18:30:01, Geoff Steckel wrote: Has 'sox' been mentioned in this context? For many simple filters, source-sox-aucat works well for me. Command line only. Yes, I'd very much like to stay on the command line for this. Would you please care to share the specifics of how you do it? Thank you very much Jan Check sox.sourceforge.net - the documentation there is good. I don't mean how to apply the sox filters (to do, say, a stereo pan). I mean the interaction of aucat and sox while recording. Or did you mean, record, then process with sox, then use in aucat again, repeat? I was under the (perhaps wrong) impression that you are doing this in real-time, thats what I was asing about. Thanks Jan
Re: the aucat recording studio - stereo panning
You'll face other problems preventing you from doing everything with aucat. First, there's no reverb, which is necessary to create the spacial feel, volume changes are too abrupt (cause small clicks) and not real-time. Implementing pan, effects and smooth parameter changes would bloat aucat/sndiod. IMO the way to go is to handle processing in small programs (with a simple record-process-play loop) and keep sndiod only for routing the signal to the hardware or other programs. Currently that's the way I handle some effects, I write small programs that apply effects on the record stream to send the result in real-time on the play stream. Then I use -mmon to record the result in a file. Not very flexible, but good enough to test the concept. If I understand what you are doing, perhaps you have another way. Noatun doesn't make the deal ? You play audio file with it and add the filter Arts::Synth_FREEVERB. It has the essential control knobs for reverb. Kaffeine has other filters for audio. Noatun Kaffeine work well with filters, parameters can be adjusted in real-time. And it should be possible to record the audio output in a file. And perhaps you will want to write new filters for them ;).
Re: the aucat recording studio - stereo panning
On 02/09/2012 06:05 PM, Alexandre H wrote: You'll face other problems preventing you from doing everything with aucat. First, there's no reverb, which is necessary to create the spacial feel, volume changes are too abrupt (cause small clicks) and not real-time. Implementing pan, effects and smooth parameter changes would bloat aucat/sndiod. IMO the way to go is to handle processing in small programs (with a simple record-process-play loop) and keep sndiod only for routing the signal to the hardware or other programs. Currently that's the way I handle some effects, I write small programs that apply effects on the record stream to send the result in real-time on the play stream. Then I use -mmon to record the result in a file. Not very flexible, but good enough to test the concept. If I understand what you are doing, perhaps you have another way. Noatun doesn't make the deal ? You play audio file with it and add the filter Arts::Synth_FREEVERB. It has the essential control knobs for reverb. Kaffeine has other filters for audio. Noatun Kaffeine work well with filters, parameters can be adjusted in real-time. And it should be possible to record the audio output in a file. And perhaps you will want to write new filters for them ;). Has 'sox' been mentioned in this context? For many simple filters, source-sox-aucat works well for me. Command line only.
Re: the aucat recording studio - stereo panning
On Tue, Feb 07, 2012 at 09:31:30AM +0100, Jan Stary wrote: Now, I can record further tracks with e.g. $ aucat -i background.wav -i solo.wav -o vocal.wav I can specify relative volumes with -v (or even control them with hardware knobs when using a midi controller); what I miss is stereo panning. heh, that's exactly what i do :) Without further options, all the previous tracks are mixed as 1/n, and positioned in the middle of the stereo panorama; that's doable, but the musical experience would be very much enhanced with stereo positioning. I mean e.g. hearing the drums in the left and the bass in the right while recording the vocals. I realize that this can be considered mixing already, and aucat does not, by design, use a full matrix mixer: it uses a 0/1 matrix (controlled with the -C/-c ranges). There are workarounds: I can pre-procces the existing tracks with e.g. SoX to attenuate/amplify the left/right channel of each, and then play these preprocessed streams. Am I right at thinking that there is currently no way to do that in aucat directly? There's no easy/handy way to adjust the pan with aucat. You still can split everything into mono files, work on them, and finally combine them in a stereo file with the appropriate volume. Somewhat unpractical. You'll face other problems preventing you from doing everything with aucat. First, there's no reverb, which is necessary to create the spacial feel, volume changes are too abrupt (cause small clicks) and not real-time. Implementing pan, effects and smooth parameter changes would bloat aucat/sndiod. IMO the way to go is to handle processing in small programs (with a simple record-process-play loop) and keep sndiod only for routing the signal to the hardware or other programs. Currently that's the way I handle some effects, I write small programs that apply effects on the record stream to send the result in real-time on the play stream. Then I use -mmon to record the result in a file. Not very flexible, but good enough to test the concept. For off-line processing, audacity might help too. Besides that, sometimes I use an external mixer and effect processor, amongst others, to change the pan, equalize and add effects to the input, i.e. I record the processed signal; which means I can't change parameters later. This might not seem flexible, but remember that that's exactly what people do during live concerts and they manage to get very good sound. -- Alexandre
