First track gets recorded into the second one

[Nachei]

Hi, I've dedicated a lot of hours of research to this and I couldn't figure it out, so hopefully some of you will remember you were a newbie once and give me a hand.

Here's the thing: I record one track, and everything goes fine. but when I try to record the next track, my computer doesn't just play back the first one, it RECORDS it onto the second one as well. Muddling it all up and over riding what I was trying to record in the new track.

The phenomenon happens both in Ardour and Audacity. In Audacity, both while running with Jack or as a standalone program.

This would lead to think that the problem is related to the inbuilt sound card. BUT, on the other hand...

the bleeding happens when I record through the computer's mic, but ALSO when I record via my Samson G-Track (it's a USB mic+interface, http://www.samsontech.com/samson/produc ... es/gtrack/). Correct me if I'm wrong, but in this case, the inbuilt card does not get used, does it? Alsamixer adds an entry called "USB Codec".

Also, I have found that this bleeding happens in two different computers. Both are laptops, and both have an HDA Intel sound card (a cheap brand, maybe? One is HDA Intel G45 DEVCTG, the other I thought I had the reference but I lost it, sorry).

So I'm totally confused now, and in a rut because I don't want to purchase blindly more gear until I'm sure that more gear would solve the problem. So any hint you could give about the causes of this would be greatly appreciated, as I cannot make any music until I solve this. I'm trying to keep this brief, but I have tried a whole lot more of things, so if there is other possibility I've missed, ask me what you think could help. Thank you.

[luster]

There is a setting in Audacity:

Edit > Preferences > Recording

Locate the setting: Overdub (under Playthrough tab)

Set it according to what you wish to accomplish.



You may also mute tracks by hand right before you unpause to record, like this:

Say you have a track or two recorded and want to record another one, but do not want to re-record the sound from the first track(s) onto the new track...

"Pause", then "Record" button, then "Mute" the tracks you do not wish to have re-recorded, then un-"Pause" to start recording.

Don't forget to set up the inputs in JACK before you un-Pause to record. Audacity does not have persistent presence to JACK. (i.e., it only appears to JACK when recording or playing back.)

Many other programs offer options similar to what is available in Audacity.

[Pablo]

So, you want to overdub but there is bleeding. How do you record? Do you use headphones?

the bleeding happens when I record through the computer's mic, but ALSO when I record via my Samson G-Track (it's a USB mic+interface, http://www.samsontech.com/samson/produc ... es/gtrack/). Correct me if I'm wrong, but in this case, the inbuilt card does not get used, does it? Alsamixer adds an entry called "USB Codec".

How do you listen to the first track in this case?

[Nachei]

Thank you so much for your answers guys. In order of testing complexity:

@Luster:

You may also mute tracks by hand right before you unpause to record

Unfortunately, that's not an option in my case, because I want to recording new tracks while I listen to the previously recorded... I do my music like that, layer after layer, and such process requires syncing: to follow the beat you have to listen to the previous tracks while you're record the new one.

@Pablo:

How do you record? Do you use headphones?

Yes, I use shell-like headphones (homemade, with earbuds and construction ear protecting headphones). So there is no possibility that the bleeding is being 'caught' from them.

Also, as a test, I once tried recording the second track without connecting headphones to the G-Track at all (i.e., no sound from the first track was generated into the air at all). Listening to the result, the bleeding on that second track happened just the same.

@Luster:

There is a setting in Audacity:

Edit > Preferences > Recording

Locate the setting: Overdub (under Playthrough tab)

Set it according to what you wish to accomplish.

Yes, I had already tried that option and its equivalent in Ardour, without result. After reading your message, I tested it again just in case I had skipped some option. Playthrough was unmarked, and the only noticeable difference when I marked it seemed to be that I could listen what was being recorded in real time through the headphones. But listening to the second recorded track later, the bleeding was present again in both cases.

Firstly I tried this software playthrough option with headphones connected (so no sound came out of the speakers). Then I unplugged the headphones, and the recording peeked with a nasty feedback screech.
----

Another possible idea: I have also found a couple of brief and isolated references to something called 'Crosstalk', which apparently happens in cheap sound cards. It wouldn't explain why the bleeding happens also when I record via G-Track, but could it be somewhat relevant?

[Pablo]

It is strange that the bleeding also happens when you capture via the samsung mic. In this case, I assume you setup the samsung mic for capture and the onboard for playback in qjackctl. Or else, how do you setup jack? And have you double-checked the jack connections?

I have an m-audio audiophile 2496 and I can overdub without problems in ardour.

[Nachei]

In this case, I assume you setup the samsung mic for capture and the onboard for playback in qjackctl. Or else, how do you setup jack?

I don't know if this is weird, but my mic only appears in Jack connections as system/capture1 (for the track recorded through the mic), and system/capture2 (for the track recorded through the mic's line in). I have never been able to make Jack record through the mic but playback through the computer. Here is what I tried this time:

In Jack configuration, the Gtrack appears as hw:1. I tried to change the 'Output device' option to hw:0, but then everything gets played AND recorded via the computer.

I also tried changing the 'Audio' parameter in configuration to 'Capture only', but Jack produces an error and cannot connect. If I choose 'Playback only', I can listen through the Gtrack headphones, but the tracks no longer have a 'system' tab to allow me recording.

Please notice that I don't understand the working of all Jack options, so if I'm missing something relevant let me know.

Also, looking at the information about GTrack in Alsamixer, it tells that the device has 'no capture controls' (because you control things from the knobs, I guess?)

And have you double-checked the jack connections?

Yes, I have, plenty of times. The only suspicious thing I can think of is something called Auditioner/out1 and Auditioner/out2, connected to Playback_1 and Playback_2, respectively. I did not fully understand the documentation about it, and don't know what's its mission, maybe it could have something to do with the bleeding?

[Pablo]

I don't know if this is weird, but my mic only appears in Jack connections as system/capture1 (for the track recorded through the mic), and system/capture2 (for the track recorded through the mic's line in). I have never been able to make Jack record through the mic but playback through the computer. Here is what I tried this time:

In Jack configuration, the Gtrack appears as hw:1. I tried to change the 'Output device' option to hw:0, but then everything gets played AND recorded via the computer.

I also tried changing the 'Audio' parameter in configuration to 'Capture only', but Jack produces an error and cannot connect. If I choose 'Playback only', I can listen through the Gtrack headphones, but the tracks no longer have a 'system' tab to allow me recording.

Please notice that I don't understand the working of all Jack options, so if I'm missing something relevant let me know.

Please, show the terminal output of these commands:

Code: Select all

cat /proc/asound/cards
arecord -l && aplay -l

Also, looking at the information about GTrack in Alsamixer, it tells that the device has 'no capture controls' (because you control things from the knobs, I guess?)

Yes. The control is hardware-only.

If you want to show your card's control configuration, amixer is similar to alsamixer but in text-only mode. Mabe I can take a look and try to guess.

Code: Select all

amixer -c1

Code: Select all

amixer -c0

The only suspicious thing I can think of is something called Auditioner/out1 and Auditioner/out2, connected to Playback_1 and Playback_2, respectively. I did not fully understand the documentation about it, and don't know what's its mission, maybe it could have something to do with the bleeding?

No, I don't think so.

[Nachei]

Here is the exit of the commands, and thank you for all your suggestions:

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amixer -c1

Simple mixer control 'PCM',0
  Capabilities: pvolume pswitch pswitch-joined penum
  Playback channels: Front Left - Front Right
  Limits: Playback 0 - 128
  Mono:
  Front Left: Playback 128 [100%] [0.00dB] [on]
  Front Right: Playback 128 [100%] [0.00dB] [on]
Simple mixer control 'Master',0
  Capabilities: pvolume pswitch pswitch-joined penum
  Playback channels: Front Left - Front Right
  Limits: Playback 0 - 74
  Mono:
  Front Left: Playback 74 [100%] [0.00dB] [on]
  Front Right: Playback 74 [100%] [0.00dB] [on]

Code: Select all

amixer -c0

Simple mixer control 'PCM',0
  Capabilities: pvolume penum
  Playback channels: Front Left - Front Right
  Limits: Playback 0 - 255
  Mono:
  Front Left: Playback 255 [100%] [0.00dB]
  Front Right: Playback 255 [100%] [0.00dB]
Simple mixer control 'IEC958',0
  Capabilities: pswitch pswitch-joined penum
  Playback channels: Mono
  Mono: Playback [off]
Simple mixer control 'IEC958 Default PCM',0
  Capabilities: pswitch pswitch-joined penum
  Playback channels: Mono
  Mono: Playback [off]
Simple mixer control 'IEC958',1
  Capabilities: pswitch pswitch-joined penum
  Playback channels: Mono
  Mono: Playback [off]
Simple mixer control 'Digital',0
  Capabilities: cvolume penum
  Capture channels: Front Left - Front Right
  Limits: Capture 0 - 120
  Front Left: Capture 60 [50%] [0.00dB]
  Front Right: Capture 60 [50%] [0.00dB]
Simple mixer control 'External Mic',0
  Capabilities: volume pswitch penum
  Playback channels: Front Left - Front Right
  Capture channels: Front Left - Front Right
  Limits: 0 - 80
  Front Left: 80 [100%] [6.00dB] Playback [off]
  Front Right: 80 [100%] [6.00dB] Playback [off]
Simple mixer control 'Internal Mic',0
  Capabilities: volume pswitch penum
  Playback channels: Front Left - Front Right
  Capture channels: Front Left - Front Right
  Limits: 0 - 80
  Front Left: 80 [100%] [6.00dB] Playback [off]
  Front Right: 80 [100%] [6.00dB] Playback [off]

Code: Select all

cat /proc/asound/cards

 0 [Intel          ]: HDA-Intel - HDA Intel
                      HDA Intel at 0x54700000 irq 27
 1 [default        ]: USB-Audio - USB Audio CODEC 
                      Burr-Brown from TI               USB Audio CODEC  at usb-0000:00:1d.1-1, full s

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arecord -l && aplay -l

**** List of PLAYBACK Hardware Devices ****
card 0: Intel [HDA Intel], device 0: CONEXANT Analog [CONEXANT Analog]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: Intel [HDA Intel], device 1: Conexant Digital [Conexant Digital]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: Intel [HDA Intel], device 3: INTEL HDMI 0 [INTEL HDMI 0]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: default [USB Audio CODEC ], device 0: USB Audio [USB Audio]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

[Pablo]

For some reason, the list of CAPTURE hardware devices which should have appeared in the output of "arecord -l && aplay -l" is missing. Can you show the output of just "arecord -l", please?

EDIT: I also suspect that the output of amixer (at least for the onboard card, c0) is incomplete. You can always write the entire output to a text file and copy from there. For example,

Code: Select all

amixer -c0 > amixer_onboard.txt 

will create a text file named amixer_onboard.txt in your home folder.

[Nachei]

Yikes, sorry about that, here are the correct outputs:

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arecord -l

**** List of CAPTURE Hardware Devices ****
card 0: Intel [HDA Intel], device 0: CONEXANT Analog [CONEXANT Analog]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: default [USB Audio CODEC ], device 0: USB Audio [USB Audio]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

Code: Select all

amixer -c0

Simple mixer control 'Master',0
  Capabilities: pvolume pswitch pswitch-joined penum
  Playback channels: Front Left - Front Right
  Limits: Playback 0 - 74
  Mono:
  Front Left: Playback 74 [100%] [0.00dB] [on]
  Front Right: Playback 74 [100%] [0.00dB] [on]
Simple mixer control 'PCM',0
  Capabilities: pvolume penum
  Playback channels: Front Left - Front Right
  Limits: Playback 0 - 255
  Mono:
  Front Left: Playback 255 [100%] [0.00dB]
  Front Right: Playback 255 [100%] [0.00dB]
Simple mixer control 'IEC958',0
  Capabilities: pswitch pswitch-joined penum
  Playback channels: Mono
  Mono: Playback [off]
Simple mixer control 'IEC958 Default PCM',0
  Capabilities: pswitch pswitch-joined penum
  Playback channels: Mono
  Mono: Playback [off]
Simple mixer control 'IEC958',1
  Capabilities: pswitch pswitch-joined penum
  Playback channels: Mono
  Mono: Playback [off]
Simple mixer control 'Digital',0
  Capabilities: cvolume penum
  Capture channels: Front Left - Front Right
  Limits: Capture 0 - 120
  Front Left: Capture 60 [50%] [0.00dB]
  Front Right: Capture 60 [50%] [0.00dB]
Simple mixer control 'External Mic',0
  Capabilities: volume pswitch penum
  Playback channels: Front Left - Front Right
  Capture channels: Front Left - Front Right
  Limits: 0 - 80
  Front Left: 80 [100%] [6.00dB] Playback [off]
  Front Right: 80 [100%] [6.00dB] Playback [off]
Simple mixer control 'Internal Mic',0
  Capabilities: volume pswitch penum
  Playback channels: Front Left - Front Right
  Capture channels: Front Left - Front Right
  Limits: 0 - 80
  Front Left: 80 [100%] [6.00dB] Playback [off]
  Front Right: 80 [100%] [6.00dB] Playback [off]

[Pablo]

Sorry, I don't know what else I can suggest. I assume you have already tried, for the G-track, every combination of alsamixer levels and the monitor mode switch.

[Nachei]

OK, thank you for trying. As a poorman's soultion, I'm going to try doing some gating. The bleeding sounds quite low when using the G-Track (however, as soon as you normalize, you hear IT'S THERE, and it sums up the more layers you add...)

Anyway, thanks you both. It's been a great opportunity to get one step ahead in the learning curve...

[luster]

What happens in Audacity if you have recorded one track, then get set to record an additional track while at the same time listening to the earlier track, like this: in Audacity looking at your first track, hit pause, then hit record (while still paused), then go to JACK and remove the input to Audacity, and then replace it with, say, a synth output such as Yoshimi, then go back to Audacity, unpause to start recording, and play the synth along with the first track onto the new track?

Do you see any bleed-through then?

[luster]

You've probably seen this, but the Audcity_team has a tutorial on overdubbing specifically with a Samson G-Track mic:

Overdubbing with a Samson® G-Track USB Microphone

Introduction

This tutorial describes a known working method of creating a multiple sound track overdubbing session from scratch in Audacity. That is, you record one track and then play it back and add a second track against it: drums, guitar, voice; repeat as needed.

This process uses a particular USB microphone that has bi-directional headphone monitoring and management built into its base.In this tutorial you will be able to hear a mix of your live recording and the previous tracks simultaneously in your headphones (also required). Live monitoring is often unavailable (or you hear yourself too late) without purpose-built hardware.

The procedure is similar for many other makes or models of USB microphones.

Hardware playthrough is not available when using a USB microphone that does not have a headphone output.
In this case you should follow the advice in Overdubbing using your computer's on-board sound card, but using your USB microphone rather than your computer's built-in microphone.

Hardware

The Samson® G-Track is a good quality, large capsule, condenser USB microphone; it has a headphone connection in its base in addition to the USB connection. ...

http://wiki.audacityteam.org/wiki/Overd ... Microphone

And you've probably also seen these more general informations from the Audacity_team as well:

http://wiki.audacityteam.org/wiki/Overd ... sound_card

http://manual.audacityteam.org/man/Reco ... references

http://manual.audacityteam.org/man/Tuto ... k_Overdubs

[Nachei]

Thank you so much Luster. It's funny, your post, in a way, brings me back a part of myself I had forgotten. I did not remember that Audacity wiki -I did the transition to Ardour like a year ago or so-, but looking back it is too much coincidence, so pretty surely I saw that tutorial and it subliminally influenced my purchasing of the G-Track. I guess it says a lot about my lack of attention towards gear; I know it might sound weird for many, but I cannot get interested in gear no matter how hard I try.

I tried following the Audacity tutorial, to see the problem with fresh eyes, and also because so far I had guided myself by the G-Track's manual. I have found two issues interesting to mention:

1)
As far as my understanding goes, there is a mistake in the tutorial. It says

in the Devices tab:

* Under Playback set Device to the on-board sound card
* Under Recording set Device to the on-board sound card and set Channels to 1 (Mono)

When I did that, Audacity listened to and played through the inbuilt computer mic. Instead, the instructions should say "set device to the mic (USB Codec)", I understand. I had to do that in order to continue with the tutorial. I'd like to report this to the Audacity team, but I wanted to comment it here first in case I am missing something.

and 2)

Solved that hurdle, I go on with the tutorial, and every goes as expected until I try to play the second track I've recorded. It is not well recorded! It sounds with kind of a 'helicopter' effect, with a rythmical chunking of the sound. If you solo that second track, it sounds with the 'helicopter effect' just the same, so the track has been badly recorded.

I doublechecked, by deleting the two tracks and then following the tutorial instructions again. Same results: track 1 gets well recorded. Track 2, chunked by the helicopter effect.

And all of this when I'm following religiously the Audacity tutorial and using the very same mic model that they use! Does anybody know something about this?