unnecessary echo recorded using StereoMix

[YoSFj]

I have been experiencing some echo (or something of the sort) added in the recorded sound using StereoMix.
I attempt to record broadcasts using the sound card internally installed in my Windows Vista 32 bit laptop.
Would you help me get rid of the echo when I record broadcasts?
Though I do not think my problem is only for Audacity but other recording applications available to me,
I have no idea how to solve this.
I updated the RealTek sound device software but the problem remains.
Mic input is clearly canceled and not activated.
I do not hear any strangeness when I hear the original broadcast directly through headset.
Thank you very much for any help.

[steve]

When you record from "Stereo Mix" you will record everything that is playing through your sound card. This is good for recording sounds that are playing through your web browser, but the down-side is that it is very easy to create "feedback" loops where unwanted signal paths are also recorded.

I attempt to record broadcasts

Not sure exactly what you mean - do you mean that you are recording an internet broadcast that is playing through your web browser?

[YoSFj]

It means that I record whilst I listen to Internet radio.
In other words, I should like to record the sound I only listen to.
The same problem occurs when I attempt to record the sound when a CD is being played.
So, you are right, choice of StereoMix appears to be the cause of the problem but how can I solve it?

[steve]

The problem is probably caused by recording from the microphone as well as directly from the Internet radio/CD. You need to mute all sound card inputs that are not being used so as to eliminate all sound sources other than the one that you actually want to record. Note that this is a sound card setting and not an Audacity setting.

The sound card may be accessible through a loudspeaker icon near the time/date on your Desktop. If not, you can access the sound card recording settings through the Windows Control Panel. (see here for some tips: http://wiki.audacityteam.org/wiki/Mixer ... trol_Panel )

For "recording" from CD, a much better method than using Audacity is to digitally "rip" the CD. Free programs that can do this include Foobar2000, C-Dex and EAC (Exact Audio Copy). Ripping a CD to a WAV file is much faster and better quality than recording the CD. EAC can provide "perfect" copies provided the CD is in good condition, but can be very slow with scratched or damaged CDs. Foobar2000 is also an excellent audio player. C-Dex is a very good CD ripper with a good balance of speed and accuracy. I would recommend installing both EAC (for use with good condition CDs) and Foobar2000 (for fast ripping and as an excellent audio player and audio format converter).

[YoSFj]

The problem is probably caused by recording from the microphone as well as directly from the Internet radio/CD. You need to mute all sound card inputs that are not being used so as to eliminate all sound sources other than the one that you actually want to record.

Yes, this is what I wrote in my initial posting.
So, only StereoMix is only activated.
This problem did not occur when I used Audacity with Windows XP so I should now think it is a matter of either RealTek software or Windows Vista.

I do not use Audacity to record sounds from CD but I just tested if the same thing happens with this route and it did.
So it is just a reinforcement of my initial problem.

[steve]

So, only StereoMix is only activated.

Yes, but that will record everything that is playing through the sound card.
If, for example, "Mic" is enabled for "playback", then that will be recorded.
You need to disable or mute unused sources from playback.

[YoSFj]

So, only StereoMix is only activated.

Yes, but that will record everything that is playing through the sound card.
If, for example, "Mic" is enabled for "playback", then that will be recorded.
You need to disable or mute unused sources from playback.

I think I understand the point fully and my setting is exactly the way you describe.
However, just in case I might have misunderstood the point, would you further tell me how to do it?

1. Recording devices
Mic: Mic level is ZERO and NOT activated. Mic boost is clearly 0.0 dB.
Line in: NOT connected so that I cannot adjust anything
StereoMixer: ON and Level Property for StereoMix 100

2. Play devices
Speaker: ON yes, I need to monitor the recording.
RealTek Digital Output: ON (nothing improved when nullified)

3. I/O settings in Audacity
I tried everything both MME and Windows DirectSound but the problem remained.

If there are other ways than using StereoMix to record the internet radio broadcast using Audacity,
would you also tell me how to do it?

Just for further information.
I directly connected between Mic and earphone using mic setting on and stereomix off.
It worked just fine and problem disappeared but I was not able to monitor the sound.

[YoSFj]

My problem appears to be the one found in the posting http://forum.audacityteam.org/viewtopic.php?f=16&t=6797.
However, in my case updating the sound card driver, RealTtek High Definition Audio, did not solve the problem.
I have no idea why. I guess the root of the problem is in either Vista or sound card driver.
Thank you again everyone.
I will post when I solve the problem.

[steve]

Having gone through all of the other options, it does indeed sound like it is probably a driver problem. Unfortunately the trend with new drivers on Windows is for disabling Stereo Mix entirely, so it is unlikely that a new driver will be released that offers a solution to the problem.

For some types of radio broadcast it is possible to download the audio without going through the sound card. When this is an option it is generally better than recording the broadcast as it is faster, and better sound quality. If you use Firefox you may find something here: https://addons.mozilla.org/en-US/firefo ... a+download

Alternatively, as you are able to record by linking Mic to earphone, you could try using a splitter cable so that you can hear the recoding while recording this way.

[YoSFj]

Having gone through all of the other options, it does indeed sound like it is probably a driver problem. Unfortunately the trend with new drivers on Windows is for disabling Stereo Mix entirely, so it is unlikely that a new driver will be released that offers a solution to the problem.

Thank you very much for this. I assume it problematic for loads of people who are interested in recording live radio broadcasts. For reference to others, do you think the problem will be found on Windows 7 as well?
Thank you very much again.