On Monday 16 December 2013 16:44:26 Fons Adriaensen did opine: > On Mon, Dec 16, 2013 at 01:10:31PM -0500, Joe Hartley wrote: > > Headphoune out is a different impedance than line out, it's really > > easy to overload a line input. I'm a little suspicious of the level > > into the main mixer though; you should have had more than enough > > signal for the board. > > Headphone outs are very low impedance, which is perfectly OK for a > line input (pro line outs are low Z as well). Most HP outs today are > designed for 32 ohm earbuds and should be able to provide sufficient > signal to a mixer line in, at least if the mixer has an input gain > control on the line input, as most have. > > But an HP out won't provide a real 'pro' line level. And beware of > the specs of some sound cards. They claim 'pro' level line outs at > +4 dBu. But more often than not, that means their peak level is +4 > dBu, while in the pro world that is the _working level_, with peaks > being 12..15 dB higher. But the average sound card, running on the system 5 volt bus is all tapped out at +4, clipping anything that goes above that. Some may tap the system + and - 12 volt for the output stage, so those will, if everything is right, still clip at +20 or so which in some music can be hit even if the meter only says +4. To hit + 30dbm takes about 16 to 17 volts on each supply rail. No computer offers that much at its pci sockets. And some, in an effort to be as power miserly as they can be, will have significant, see it on the o-scope, cross-over distortion at any level. Driving the average earbud, they can get away with murdering the music & few can hear the diff. Sad but true too many times. > > I suspect there was some user error at the mixer. > > Yep. Or the system just wasn't as powerful as the OP believed it was. > > Ciao, Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> Horner's Five Thumb Postulate: Experience varies directly with equipment ruined. A pen in the hand of this president is far more dangerous than 200 million guns in the hands of law-abiding citizens. _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user
