Question about Mic Input slider

[prolificwackoman]

I host an internet radio program, and record each show through Audacity. I use an MXL 990 mic, and sound from my computer goes out through the headphone jack, into my Behringer Eurorack UB1002 mixer, and back into my computer via the mic jack. During the broadcast/recording of my most recent show (the first I've done with the MXL mic), I noticed that the Mic Input slider was automatically adjusting itself as I spoke. Mind you, I monitor my levels through the VU meter built into the Edcast encoder I use, and my mic was initially turned up where I was hitting "yellow" levels (around -15dB.) My co-hosts use (respectively) an AKG mic and two Radio Shack mics - the AKG has an XLR connector, while the Radio Shack mics have line in cables.

Tech garb aside, as I said, I noticed the Mic Input slider was automatically adjusting itself as we all spoke. It would automatically lower itself to about 0.3 from between 0.8 and 1.0. This is an issue I've NEVER had before until now, and I'm wondering if this was just a software glitch or what. If this is common, is it possible to adjust the settings so the slider doesn't automatically move at all?

Thanks,
Jack

[steve]

I noticed the Mic Input slider was automatically adjusting itself as we all spoke.

That's amazing - Audacity does not do that I guess Audacity must be responding to changes that your sound card driver is making. Some sound cards (notably PC laptops) have various kinds of Automatic Gain Control (AGC), noise reduction, and other recording "enhancements" that play havoc with making high quality recordings. There is often a way to switch these effects off though the settings can be well hidden (look to the icons near the computer clock, and filing that, the Windows Control Panel).

If you are using the on-board sound card, the better solution is to upgrade the sound card. Behringer and Edirol make inexpensive USB line-level audio devices that do the job nicely. The Behringer UCA 202 is the cheaper option - the Edirol UA-1EX is better specified. Either of these devices will be much better quality than an on-board sound card.

[prolificwackoman]

Hm, I'll look into those. I have a feeling it might have been some weird software issue. I have a Vinyl AC'97 WAVE card, and again, have never had an issue like that. I've been messing around with Audacity - muting my speakers/headphones, cranking up EVERYTHING to the max, and just recording a few minutes of extremely overmodulated sound. The slider stays in place, so like I said, hopefully it's a software issue.

[prolificwackoman]

Steve,

Would you be able to point me in the direction of those settings? I'm aimlessly looking around the Control Panel

[kozikowski]

Did it go down when you started talking and drift back up when you stopped?

Windows PCs naturally assume you're using them for corporate telephone calls or video conferencing. That's why they have Line-Out (for headphones) and Mic-In from the microphone connected to the headset. Like this...

http://www.labtec.com/index.cfm/gear/li ... =8,crid2=9

Any of those will plug right into a PC and Vonage dial the head office in Geneva. No sweat.

To get that to work reliably, they have to use automatic microphone gain and processing. We think that's what's happening to you. Somehow, that process got turned on, or failed to get turned off.

<<<Eurorack UB1002 mixer, and back into my computer via the mic jack.>>>

I would have assumed a connection like that wouldn't work. That is an enormous mismatch in sound levels. A microphone produces a thousand times quieter sound level than the output of the mixer. Your computer may have provision to switch the Mic-In to use Line-In (mixer) sound levels. Some do. Lenovo's have both Line-In and Mic-In on the side of the case.

Did you recently put Vonage or Skype on that machine? Both of those are Sound Level Nazies. They take over and you will do what they want.

Koz

[steve]

Would you be able to point me in the direction of those settings?

Unfortunately different manufacturers hide the settings in different places - it can even be different from one computer model to another, and sometimes computers of the same make and model will have those settings in different places. It has been reported that on some computer those settings are not available for the user at all (though that may just be that the user has been unable to find them).

The most common place is in an icon near to the system clock. You will probably have to tell windows not to auto-hide icons, and then check what each icon is. If it is not there, then look in the Control Panel and see if there is an icon relating to your AC'97 sound card, or possible in "Sounds and Audio Devices".

Again, if you are using the on-board sound card, upgrading the sound card is likely to offer much better performance, less headaches, and solve the level mismatch issue that Koz mentioned.

[prolificwackoman]

Thanks guys... yeah, I ran Skype for the whole show, as we were connected to TalkShoe (to enable a chatroom of sorts.) We've never done that before until last week, and ironically enough, we had that issue with the mic slider on that same show. I am looking into the external sound card - I had no clue about the level mismatch. We're doing our show again tomorrow night, so I'll let you guys know if we had any more issues.

[prolificwackoman]

Hi Guys

I finally discovered what the issue was with Audacity... it had nothing to do with Audacity. Well, almost nothing.

On Skype, there is a button that says "Let Skype Adjust My Audio Settings." With that button checked, Skype takes over your computer, and will automatically mess with Audacity's sliders. I turned that setting off, and guess what! No more problems!

Thanks again for the help!

[kozikowski]

<<<Thanks guys... yeah, I ran Skype for the whole show, as we were connected to TalkShoe (to enable a chatroom of sorts.)>>>

This may be the answer to the question that pops up on the boards regularly. Multiple microphones and VOIP with sound effects coming from the computer all mixed into a podcast. I would have bet you couldn't do that at all because of the VOIP services if for no other good reason. I can totally do it with two computers. Complex shows suddenly become really simple when you split off the recording function onto a different machine.

Describe the rest of your system.

Koz