Jeese I'm a nerd nerd nerd. Nerd is the word.....
Dec 14, 2022 8:12:43 GMT -5
Auf Kiltre and markfromhawaii like this
Post by ninworks on Dec 14, 2022 8:12:43 GMT -5
I have been trying to identify the sonic differences between all my mic preamps. I have 5 different high-end options at my disposal. I recently recorded a 12 string acoustic guitar track on a song using 5 different preamps at once and recorded them all to their own individual tracks so I could do a comparison between them to see what, if any, differences I heard. My conclusion is that I wouldn't hesitate to use any of them for recording anything at all but there are some small differences. I'm talking really REALLY small differences. I could hear some but they are so small they are very hard to identify. I wanted to be able to qualify and quantify the specific differences. That is hard to do just listening to different acoustic guitar tracks in headphones. That's when I had an idea.
What if I were to flip the phase (polarity) of one of the tracks 180 degrees and listen to each of the others individually along with it? Since all of the preamp tracks were of a single performance then theoretically they should null and be completely silent when played together in pairs. Anything that was still audible would be the differences between them. The first thing I did was to zoom in on all the tracks and made sure they were all time aligned down to a single sample. Then I ran my tests while manipulating the volumes of the tracks to make certain they were all precisely the same. Sunnuvagun......that worked. There were small bits of frequencies left over from the different tracks that I could actually hear and identify.
I decided I need to take that test one step further but I haven't done it yet. Since an acoustic guitar has a somewhat limited frequency range I need to record some full spectrum pink noise through all of the preamps at once and then run the same polarity-swap-null-tests again. That will identify all of the full-spectrum frequency differences between all the different preamps. Then I can use a real time spectrum analyzer to put specific numbers to those differences and log it to have a reference. This will not identify any dynamic range differences but that's some tests for another day that I'll have to come up with some procedures for. I'll probably need a square wave pulse generator and oscilloscope for that.
Mixing and matching microphones with different preamps to get the best combination for whatever instruments or voices I'm recording is something that could make a noticeable difference in the sound of a track. Once I get a better grasp of the differences in the preamps the more creative I can get with my choices of which there are many.
I find this stuff fascinating. Yes, I'm a nerd and I don't have a problem with that. I could be spending all my time watching reality TV shows.
Yes GBfun. I have been playing my guitar more.
What if I were to flip the phase (polarity) of one of the tracks 180 degrees and listen to each of the others individually along with it? Since all of the preamp tracks were of a single performance then theoretically they should null and be completely silent when played together in pairs. Anything that was still audible would be the differences between them. The first thing I did was to zoom in on all the tracks and made sure they were all time aligned down to a single sample. Then I ran my tests while manipulating the volumes of the tracks to make certain they were all precisely the same. Sunnuvagun......that worked. There were small bits of frequencies left over from the different tracks that I could actually hear and identify.
I decided I need to take that test one step further but I haven't done it yet. Since an acoustic guitar has a somewhat limited frequency range I need to record some full spectrum pink noise through all of the preamps at once and then run the same polarity-swap-null-tests again. That will identify all of the full-spectrum frequency differences between all the different preamps. Then I can use a real time spectrum analyzer to put specific numbers to those differences and log it to have a reference. This will not identify any dynamic range differences but that's some tests for another day that I'll have to come up with some procedures for. I'll probably need a square wave pulse generator and oscilloscope for that.
Mixing and matching microphones with different preamps to get the best combination for whatever instruments or voices I'm recording is something that could make a noticeable difference in the sound of a track. Once I get a better grasp of the differences in the preamps the more creative I can get with my choices of which there are many.
I find this stuff fascinating. Yes, I'm a nerd and I don't have a problem with that. I could be spending all my time watching reality TV shows.
Yes GBfun. I have been playing my guitar more.
