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2nd track flatlining

Posted: Sun Apr 04, 2010 10:18 am
by Raistx
Hello All,

I'm using build 1.3.11 on windows XP, recording from a mic plugged into my sound card.
My problem is that the second track wont record, it just flatlines.
I was getting the latency error where the the recording line just flashes at the start off second track and have reset the audacity.cfg file.
I think my recording device is set correctly because the first track is fine but the 2nd is not receiving a signal.
Even if I generate a clicktrack as the first track, the 2nd won't record.

Any ideas on what could be the problem? do you need more info?

Thanks.

Re: 2nd track flatlining

Posted: Sun Apr 04, 2010 5:13 pm
by whomper
i am thinking if you have one mike you are recording one channel and there is no signal for the other one. if you want two channels you do need two mikes, or to record in mono and then convert to stereo later. stay tuned. the fiddle guy will tell you where i am wrong real soon now.

Re: 2nd track flatlining

Posted: Mon Apr 05, 2010 1:41 am
by Raistx
Thanks for the tip :)
Unfortulantely the default is set to mono.

Re: 2nd track flatlining

Posted: Mon Apr 05, 2010 4:04 pm
by whomper
okay
you need to be very specific
which default is mono. lots of software pieces get involved here.
tell us all the hardware make/model and all the settings/options in all the software and what did you do push/click/whatever while recording

with one mike (usually mono) you have one electrical signal (unless it is a magic stereo mike that delivers two of them)
so you get one channel recording unless you can tell the software to record it on two channels.

if you really have mono set then what is the other channel that is flatlining? you only get one track with mono. with stereo you should get one track recording from the mike and the other one flatlined unless you do something to change taht.

you can take one mono track and double it to stereo so you can hear it out of both speakers if that is your intent.

Re: 2nd track flatlining

Posted: Tue Apr 06, 2010 11:53 am
by Raistx
OK, I don't think I'm explaining myself properly.

Nothing to do with channels, I'm talking about tracks.

Lets say I record a rhythm guitar part,press record, mics infront of the amp,i play the guitar, press stop, no problem, records fine.
Then I want to record a lead guitar part over it.
I press record again, audacity creates a new track, which does not receive a signal from the mic.
track.JPG
track.JPG (53.38 KiB) Viewed 1133 times
The original device settings were like this but then I get a latency error.
device2.JPG
Default device settings
device2.JPG (34.34 KiB) Viewed 1133 times
I changed to this then the track seems to be recording but not receiving a signal.
device.JPG
device.JPG (34.48 KiB) Viewed 1133 times
I'm really not sure what the problem is, I'm guessing the hardware is setup correctly or I wouldn't be able to record on the first track either.

Re: 2nd track flatlining

Posted: Tue Apr 06, 2010 2:12 pm
by whomper
i would say it is impossible but somewhere there msut be one key item that you are overlooking to tell us. if it records from the mike and you stop. then you try again -- it is going to record from that mike unless you changed something (or some ghost changed something). if you get it to work then dont change anything!
maybe one of the developers can spot the problem. if nobody else replies then post this in complete detail under bugs and see what responses you get.

Re: 2nd track flatlining

Posted: Tue Apr 06, 2010 11:04 pm
by steve
Hi Raistx,

Have a look at the bottom of the "Transport" menu.
Is "Software Plythrough" selected?
If it is, try deselecting it.

Re: 2nd track flatlining

Posted: Wed Apr 07, 2010 8:28 am
by Raistx
Hi Steve,

I think your on the right track.

Its not "Software playthrough" thats the problem but when I switched "overdub" off in the same menu it records fine as below.
nearly working.JPG
nearly working.JPG (58.36 KiB) Viewed 1109 times
But..... now I can't hear the first track while recording the second. I was planning on listening to the first track on headphones while recording from my amp with a mic.

Getting closer :)

Re: 2nd track flatlining

Posted: Wed Apr 07, 2010 12:00 pm
by steve
It seems that your sound card is not providing "full-duplex" (simultaneous bidirectional) data.
Virtually all sound cards of the last 10 years have supported full-duplex, so I wonder why yours is failing.

What do you have set as the default sample rate?
(Edit menu > Preferences > Quality tab)
Try setting it to 44100 or 48000
Restart Audacity after changing the setting and test.

Re: 2nd track flatlining

Posted: Wed Apr 07, 2010 12:35 pm
by Raistx
That didn't work Steve.

My sound card is a C-Media CM6501 built in on a ASUS M2N-PLUS Sli motherboard.
I just checked in control panel sound settings and CM6501 utility and couldn't find anything relating to full duplex.
the drivers are up to date, it could be a faulty card??

Maybe it would be easier to buy a new sound card.

Thanks for your help.