I'm looking for something to limit my headphone volume when listening on my PC, when it goes over a certain threshold. I have seen expensive commercial devices but would like to know if there are any DIY or build-able circuits to mute when the audio is too loud? I have tried software audio compressors but they add too much latency.
I read that a pair of zeners can do audio clipping and there are these chips http://www.njr.com/semicon/PDF/NJM2761_E.pdf but it says that the limit range is 200mVrms to 1Vrms. My multimeter shows the line out of my PC during playback is at 0.005V on a comfortable listening level and 0.012V when excessively loud. Would the actual output from my PC be higher than my multimeter is able to capture on AC?
Thanks
Use the audio compressor, 'Loudness Equalization' built into Windows & set it's response setting to 'Short' instead of 'Long'. It's really reactive and makes all Youtube videos sound at 1 volume without soft volume portions, then, a blast during a commercial interruption, or another Windows app. Setting it to 'Long' gives that annoying short loud burst delay before it kicks in, then when the sound is low, it takes a few seconds to volume up instead of instantly...
Remember to un-install all crummy third party volume peak limiters which don't respond according to how the human ear perceives actual loudness, not signal peaks.
And remember to set each set of speakers you want the feature on. For example, you can set you headphones output to Volume Equalize while simultaneously set the HDMI audio out not to do so your surround movies play properly instead all at 1 volume. You can always do both if you like.
Except for FFDshow's internal audio limiter (an old obsolete Direct show Audio&Video decoder), all other software limiters I've heard don't respond quickly enough, though they may be good enough for music. Setting Window's built in version to 'Short' is lousy for music since everything always comes out at exactly 1 monotone fixed volume, though it's excellent for News, talk radio and regular TV.