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I've got some problems with audio clipping because the audio levels in our church are vary greatly.
I am using a onboard soundcard and I've set the input level to 40% in Windows.
My 'Darkwood Design'soft VU meter (freeware) shows directly the line in level and stays in most cases under -3dB.
But what can I do when it is clipping anyway?
I can decrease the vMix audioinput level, but my sound card then is still clipping, I guess.
(the vMix level is not linked to the Windows mixer like in some other programms, shouldn't that be easier?
Because the input levels in Windows 7 are pretty well hided)
I can decrease my sound card input level in Windows to 20% so that it will never goes over 0dB.
But then I have to use the gain in vMix to bring the level back to a normal level.
Is this recommended and doesn't that affect the audio quality?
Does a software gain prevents clipping?
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Taken from http://www.darkwooddesigns.co.uk/pc2/meters.htmlQuote:This meter indicates only what is fed into the wave input channel. To monitor playback output levels you have two options: 1. use the Windows Mixer ‘What You Hear’ option if you have it. Often Vista and Windows 7 do not, but see the note below about enabling this feature. 2. Feed the wave output back into the wave input, either externally with a cable. These meters can be very useful operated in this way but for accurate work you would need to calibrate it. As an aid to calibration here is a Calibration Tone Wave File you can download*. This is a 400Hz tone recorded at a level of 4dB below Full Scale Digital. Playback this file and set up the meter so this reads '6' or +8dB on the scale, or just at the start of the red. http://www.minorshill.co...0Full%20Scale%20-4db.wav So the levels shown on the scale on the software VU meter require you to callibrate the software before trusting them as being accurate, so unless you aer able to acllibrate, ignore the levels. What I'd advise is to reduce the output from your external audio source as it is too high a gain. If that source comes through a mixer, make sure you're taking a line-level output, and check if that output is 'consumer' (-10dB) or 'professional' (+4dB) level - pro kit will give a higher output level, thefore be 'louder' for your soundcard input, which will probably be expecting 'consumer' level audio
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The vu meter I am using has a source selection and it is monitoring 'line in'.
I didn't calibrate it, but when it is going over 0dB then I hear distorsion in my recordings, so it is pretty accurately.
I don't use any outputs from the soundcard, only line in.
The 'listen' option generates a delay, I never use that option.
I am feeding the line output from a professional 19" PA mixer directly to the soundcard and it has no adjustable output level.
But what is the recommended line in level in Windows: 100% instead of 40%?
I can adjust the audio signal with a passive stereo fader, but I like to do it in vMix.
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Most PA mixer outputs will run too hot for computer line inputs. We have ours down to 15-20% on the soundcard.
What output out of your mixer are you using? What type of mixer are you using?
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The mixer we use is a Dutch product from STI Acoustics. It is a digital stereo mixer: See the leaflet hereThe stereo output is a standard line output. But how about decreasing the input level in Windows to be shure that there is no clipping and using gain in vMix?
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Do you have any outputs from the mixer you can control the level to the computer?
How we handle our sound into the computer is we use an Aux out from the mixer going into the Soundcard Line In. We will monitor that audio while watching windows levels and listening. We usually have to set our PA Mixer Aux OUT to a level that doesn't cause distortion/clipping. You will also probably find you need to set your Soundcard Line In level anywhere between 10-20%. Most Computer soundcards aren't designed to handle the levels of signal from a mixer. After we get the sound OK coming into the computer then we bring in VMIX. You can bring the gain up in vmix if you need to but usually I find we don't need to do that.
Another thing is to take advantage of the compression feature in VMIX. It is great for keeping signals from getting too high and overdriving. We usually shoot for an average of -10db as a constant output which leaves headroom with no clipping. We also eyeball the vmix meter to run around 80% or so and we don't have too many problems with the audio.
If you can't control the volume to keep it steady from the mixer going into the computer then you will find you might have problems with incoming audio getting too high for that soundcard. You usually find this problem when people are using the mixer to mix a PA system and they use the same output to go into the computer. As they increase the volume for use with the PA it could distort the signal going into the computer.
I hope this helps some.
Kirk
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The output of our mixer is fixed.
The clipping only occurs when a live band is playing very hard or the organ has all registers open, in most cases the sound is OK.
I did decrease the input level to avoid clipping, but some of our listeners where complaining that the volume of our broadcast streams were too low.
I tried some professional compressors, but the result was a very unnatural, restless sound.
I didn't test the compressor in vMix yet, what ratio setting do you use?
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Glad you were able to get it taken care of.
I usually run about a 6:1 ratio in VMIX.
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A little bit late, but I am wondering: what is the use of the compressor?
When the sound card input is not clipping there is no distortion and vMix doesn't have to reduce the signal.
When the sound card input is clipping then vMix can't repair the distortion anyway.
The input and master faders are only attenuators and the gain is added after the compressor, so the compressor can't have a clipping protection function.
Which option is the best one to get the maximum volume level and best sound quality out of vMix:
A. fixed output -> ................................................sound card (level 20% -> -3dB at loudest music) -> vMix (gain=+6dB) when music gets louder -> decrease vMix input level
B. fixed output -> passive volume control -> sound card (level 80% -> -3dB at average music) -> vMix (gain=0) when music gets louder -> decrease passive volume level
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