View All Students
Diego Pacheco
September 7 12:00-5pm
For this chapter I have learned about digital audio and its relation to analog. A signal is processed through a microphone and sent to a ADC which reads the voltage signal and processed to a DAC. The DAC sends the sample to Pro Tools and is read as a wave file. In the digital realm the signal is processed (amplitude signal voltage) with a bit rate, the bit rate can be different so to get the most out of the sample we would choose a high bit rate. the more samples in a wave form the higher the bit rate. Donny said that in the studio we use 48khz and a bit rate of 24 to eliminate in error in processing a signal, also to capture as many samples possible. if we were to use less then the wave will have distortion or samples missing. the Nyquist Thereom states that in order to capture all frequencies the sample rate must be two times higher than the sample being recorded, otherwise the computer would not be able to read all samples within that range. to help with this a low pass filter removes any frequencies above the Nyquist Thereom, that way no clipping is being processed into a signal or wave. the way Donny explained this was that samples sometimes are too high in amplitude and the computer doesn't recognize that and if its then processed into the samples there is a clip created or the samples have distortion in them. because the computer reassigns every sample based on an algorithm it sometimes moves samples over or up and down to where it thinks it should be. we discussed some of the file formats covered in the lesson and simply put we need to use loss less compression formats. this is because when dealing with compression it can sometimes take away tiny bits of a sample out which creates a different sound than the original or a much lowered volume of the track. mp3 is probably the most common file format used but it takes away so many samples that we get a dumb down version of the track. the only reason why its so popular is because its a much smaller format and therefore people can load more songs into a mp3 player or whatever they use. for me this lesson helped me a lot to understand as to why i have not been having the most clarity in my own music! i went back to change all my sample rates on my music software and it made that much more of a difference when exporting files as a song. i could actually hear and understand what was happening to my wave files as i listened back. i also understand why most engineers don't like to use 100 compressor. it can really mess with your mixdown or over all sound. for a while i had been recording vocals at different sample rate than my own music and could hear the lag in my wave files and never did it occur that nyquist thereom was in play. i must say so far i really like what my mentor Donny has to offer when it comes to knowledge on engineering. also i got invited to sit in on my second session. YAY!
