jotweakfreq.com Posted November 21, 2012 Share Posted November 21, 2012 hi everybody, iv got a question for everyone that follows level metering. i used 2 audio tracks and on each i put the tone generator and generated 500hz and 1khz at -12 db each . WHy is it that the peak meter on the stereo bus is showing me -6DBFS??????? can anyone explain please...its really freaking me out to know that i thought that the peaks showed me the loudest frequency... thanks Quote Link to comment Share on other sites More sharing options...
David Nahmani Posted November 21, 2012 Share Posted November 21, 2012 Because you're summing two signals into one. And 1+1 = 2. Well... it's a bit more complex really, because you're summing periodic signals, but in your example, if the waveform are in phase, then they will both meet their peaks simultaneously, thus they add up. Quote Link to comment Share on other sites More sharing options...
jotweakfreq.com Posted November 21, 2012 Author Share Posted November 21, 2012 bbut one signal is 1khz at -12 db and the other is 500hz at -12 db...they are both sine waves ....how is my peak going to be 6 db higher???? i mean how do i mix now...im sooo sooo confused Quote Link to comment Share on other sites More sharing options...
jotweakfreq.com Posted November 21, 2012 Author Share Posted November 21, 2012 At first when i thought i understood the master bus peak meter i always thought that in the mix when similar frequencies were present, they added and therby the stereo bus peak went up for which one would compensate by equing the clash frequency and bringing the peak down...but here the addieiton is occuring wiht frequencies that are not clashing at all so what am i seeing in that meter??? really Quote Link to comment Share on other sites More sharing options...
David Nahmani Posted November 21, 2012 Share Posted November 21, 2012 bbut one signal is 1khz at -12 db and the other is 500hz at -12 db...they are both sine waves ....how is my peak going to be 6 db higher???? i mean how do i mix now...im sooo sooo confused Well if they were not periodic signal, just static voltages, and one of them was 1 volt, and the other one was 1 volt, and you summed them onto the same mix bus, you'd get 2 volts, right? Now picture two periodic signals and you have to sum their values at every time interval: sometimes they'll both be peaking at the same time therefore you'll have to sum their voltages. That's how the peak of the sum will be higher than the peak of each individual element. Quote Link to comment Share on other sites More sharing options...
David Nahmani Posted November 21, 2012 Share Posted November 21, 2012 At first when i thought i understood the master bus peak meter i always thought that in the mix when similar frequencies were present, they added and therby the stereo bus peak went up for which one would compensate by equing the clash frequency and bringing the peak down...but here the addieiton is occuring wiht frequencies that are not clashing at all so what am i seeing in that meter???really Your English is really hard to read, sorry - I have no idea what you mean here. Quote Link to comment Share on other sites More sharing options...
jotweakfreq.com Posted November 21, 2012 Author Share Posted November 21, 2012 sorry for the bad english! What i assumed all this while is that common frequencies add up and uncommon frequencies don't.... but this experiment is showing me something else....so im a bit confused on how to mix with the meter. thanks Quote Link to comment Share on other sites More sharing options...
David Nahmani Posted November 21, 2012 Share Posted November 21, 2012 I'm not sure what you mean by "uncommon" frequencies.. but yes, audio signals do add up and the peak of the sum is typically going to raise as you sum more and more signals, even if they are unrelated, even if they are not periodic, for example if summing different noise sources, the peak of the sum will still be greater than each element being summed. Quote Link to comment Share on other sites More sharing options...
redlogic Posted November 22, 2012 Share Posted November 22, 2012 but this experiment is showing me something else....so im a bit confused on how to mix with the meter. Calm down It's just music Don't worry about getting all Einstein on the meters Mix with your ears...not your eyes Just don't clip the Stereo Out Quote Link to comment Share on other sites More sharing options...
Eriksimon Posted November 22, 2012 Share Posted November 22, 2012 Here's clarity in a pdf: viewtopic.php?t=57055 Quote Link to comment Share on other sites More sharing options...
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