What is Mastering, really?
What is Mastering? Do I really need it? Where did it come from? Is it even necessary?
Let's start at the beginning. The most popular of the early mediums for recorded music was the vinyl record. The first 12" records were made in 1903 and ran at about 78 revolutions per minute. There were a variety of materials that manufacturers used for the discs, but eventually vinyl became the industry standard. (Introduced by RCA in 1931)
The length of the song on a 10 inch disk was 3 minutes at the longest. The 12 inch record offered a 4 and 1/2 minutes as the maximum song length. That is the reason that most modern songs in the last 75 years are from 2 to 4 minutes.
In 1949 RCA introduced the 45 RPM disk format, which was a big hit for the next couple of decades. Columbia introduced a Long Play 10 inch disk at about the same time, and during the 1950's, the 12 inch record played at 33 1/3 Revolutions Per Minute became the standard format for home audio. The first stereo records were offered in the late 1950's (1958), but few people had the equipment to play them in stereo until the 1960's.
The 12 inch vinyl LP (Long Play) (33 1/3 RPM) record was the standard in the 50's, 60's, 70's, and 80's. The CD (Compact Disc) was introduced in 1983 and was the standard in the 90's. After that, iPod and downloaded files have become the standard for the acquisition of audio music for the consumer. Vinyl records and CD's are still viable mediums and have their fans around the world.
One other note here is that a vinyl record had a maximum of 18 to 23 minutes on a side, thus making the total album 36 to 46 minutes in length. When CD's started being produced, the albums were often in both mediums, so the 40 to 44 minute max became a standard length for a CD, even though a CD could hold as much as 74 minutes of audio.
A vinyl record had trouble reproducing the lows and the highs with the technology available at the time, so in 1951, the Audio Engineering Society developed an equalization curve that meant that the grooves could be cut with less low and high energy. Upon playback, the lows and highs were added back, resulting in more frequency range than would otherwise be possible. This was called the RIAA equalization.
Now we come to the issue of making a master stamper for the vinyl record production. The signal went through EQ and compressors on it's way to the stamper and a good Mastering Engineer could tweak the controls and get a little bit better sound on the record for the home listener. The best in the business (Like Doug Sax (1936-2015) in Los Angeles) would experiment until they could maximize the fidelity within the constraints of the very limited medium of vinyl.
Later the same principles were applied to CD mastering and now can be applied to digital file mastering. We will take a look at what those principals are.
The basic objective of recording is to take the sound of a live musical event and put it into a form that results in an audio event that is as close as possible to the original live event. That is the basic objective, and mastering is to help recording and mixing to achieve that end.
Live events can have very large dynamic range and that can be a problem for electronic reproduction. It was a problem for vinyl, but the slight use of compression or raising the level of the quietest passages resulted in a mostly pleasing compromise.
Here is an example of a movement from a violin concerto which does not get very loud, but still shows the dynamic range.
The length of the song on a 10 inch disk was 3 minutes at the longest. The 12 inch record offered a 4 and 1/2 minutes as the maximum song length. That is the reason that most modern songs in the last 75 years are from 2 to 4 minutes.
In 1949 RCA introduced the 45 RPM disk format, which was a big hit for the next couple of decades. Columbia introduced a Long Play 10 inch disk at about the same time, and during the 1950's, the 12 inch record played at 33 1/3 Revolutions Per Minute became the standard format for home audio. The first stereo records were offered in the late 1950's (1958), but few people had the equipment to play them in stereo until the 1960's.
The 12 inch vinyl LP (Long Play) (33 1/3 RPM) record was the standard in the 50's, 60's, 70's, and 80's. The CD (Compact Disc) was introduced in 1983 and was the standard in the 90's. After that, iPod and downloaded files have become the standard for the acquisition of audio music for the consumer. Vinyl records and CD's are still viable mediums and have their fans around the world.
One other note here is that a vinyl record had a maximum of 18 to 23 minutes on a side, thus making the total album 36 to 46 minutes in length. When CD's started being produced, the albums were often in both mediums, so the 40 to 44 minute max became a standard length for a CD, even though a CD could hold as much as 74 minutes of audio.
A vinyl record had trouble reproducing the lows and the highs with the technology available at the time, so in 1951, the Audio Engineering Society developed an equalization curve that meant that the grooves could be cut with less low and high energy. Upon playback, the lows and highs were added back, resulting in more frequency range than would otherwise be possible. This was called the RIAA equalization.
Now we come to the issue of making a master stamper for the vinyl record production. The signal went through EQ and compressors on it's way to the stamper and a good Mastering Engineer could tweak the controls and get a little bit better sound on the record for the home listener. The best in the business (Like Doug Sax (1936-2015) in Los Angeles) would experiment until they could maximize the fidelity within the constraints of the very limited medium of vinyl.
Later the same principles were applied to CD mastering and now can be applied to digital file mastering. We will take a look at what those principals are.
The basic objective of recording is to take the sound of a live musical event and put it into a form that results in an audio event that is as close as possible to the original live event. That is the basic objective, and mastering is to help recording and mixing to achieve that end.
Live events can have very large dynamic range and that can be a problem for electronic reproduction. It was a problem for vinyl, but the slight use of compression or raising the level of the quietest passages resulted in a mostly pleasing compromise.
Here is an example of a movement from a violin concerto which does not get very loud, but still shows the dynamic range.
The dynamic range of the live event is actually greater than what you see and hear in this recording, but it is close enough that nobody will complain. The loudest section is still not distorted and the fidelity is still remarkable on an audiophile playback system. Although the dynamic range of vinyl requires the engineer to reduce the difference between the lowest level and the highest level, the vinyl still is able to supply enough dynamic range to satisfy the pickiest audiophile. If we say, for arguments sake, that a CD or digital file can handle the same dynamic range, then this performance can easily be transferred without loss of fidelity.
It turns out that the electrical equivalent of this dynamic range, without damaging or distorting the waveform, equals about -16 dB LUFS (or LKFS) with a waveform peak at about -1 dB. This means that all the great recordings of the last 60 years, all the recordings made for vinyl, and all the recordings being made today, can fit into the same "box" without any distortion. EQ is easily accomplished here as well.
That is the reason that many of us would like to see this standard in music today. Even music that has a very small dynamic range can fit into this box and not have any distortion of it's waveform. If a louder volume level is desired, the level control on most all preamps will be able to make the desired change in level.
The mastering engineers of the vinyl years were limited by the medium, but the limit was manageable and close enough to the original that everyone was happy. The early years of CD mastering were without problems because the level was the same electrically ( for years the same master was used for both vinyl and CD) and all the music fit in the medium as it always had.
When it dawned on the producers that they had the ability to push the electrical level of the music a little higher on the CD, they pushed more and more until they distorted the waveform peaks and then they kept pushing. See the Loudness War page for a chart that I made from recordings in my possession that show how mastering engineers started pushing the limits and the clipped samples show that they pushed beyond the limits, even after they had already completely distorted the waveforms through ridiculous amounts of poorly applied compression.
It turns out that the electrical equivalent of this dynamic range, without damaging or distorting the waveform, equals about -16 dB LUFS (or LKFS) with a waveform peak at about -1 dB. This means that all the great recordings of the last 60 years, all the recordings made for vinyl, and all the recordings being made today, can fit into the same "box" without any distortion. EQ is easily accomplished here as well.
That is the reason that many of us would like to see this standard in music today. Even music that has a very small dynamic range can fit into this box and not have any distortion of it's waveform. If a louder volume level is desired, the level control on most all preamps will be able to make the desired change in level.
The mastering engineers of the vinyl years were limited by the medium, but the limit was manageable and close enough to the original that everyone was happy. The early years of CD mastering were without problems because the level was the same electrically ( for years the same master was used for both vinyl and CD) and all the music fit in the medium as it always had.
When it dawned on the producers that they had the ability to push the electrical level of the music a little higher on the CD, they pushed more and more until they distorted the waveform peaks and then they kept pushing. See the Loudness War page for a chart that I made from recordings in my possession that show how mastering engineers started pushing the limits and the clipped samples show that they pushed beyond the limits, even after they had already completely distorted the waveforms through ridiculous amounts of poorly applied compression.
Below is the waveform for the best original song from 1994 sung by Elton John "Can You Feel The Love Tonight"
It is well recorded, well mixed and well mastered. Note that every peak has it's own level, it has a dynamic range of 8.7 dB, and fits perfectly into that -16 dB LUFS, -1 dB True Peak "box". There is no distortion of any kind and it has soft and loud passages.
It is well recorded, well mixed and well mastered. Note that every peak has it's own level, it has a dynamic range of 8.7 dB, and fits perfectly into that -16 dB LUFS, -1 dB True Peak "box". There is no distortion of any kind and it has soft and loud passages.
That is what mastering is supposed to be. As close as you can get to being in the studio listening to the orchestra.
If you stick on a compressor and slam the level, it might look like this ('Closer' by the Chainsmokers off of the 2017 Grammy CD)
The dynamic range is 7.7 dB, the LUFS is -7.7 dB, True Peak level is +2.4 dB (!!), and about 23,000 clipped samples! Compare that to the above example 8.7 dB -16.0 dB -1.0 dB and 0 clipped samples.
If you stick on a compressor and slam the level, it might look like this ('Closer' by the Chainsmokers off of the 2017 Grammy CD)
The dynamic range is 7.7 dB, the LUFS is -7.7 dB, True Peak level is +2.4 dB (!!), and about 23,000 clipped samples! Compare that to the above example 8.7 dB -16.0 dB -1.0 dB and 0 clipped samples.
Hopefully you can see why requiring a standard of -16 dB LUFS and -1 dB True Peak Level would save an awful lot of music from the distorted mess we find ourselves in today.
The loudness difference between these 2 tracks is about 8.3 dB. That means that you need to turn down the second example by that amount to match the first piece. Except that it actually would sound better to turn it down by about 20 dB, but that is a different issue.
In this video I take a look at Adele's 'Rollin' In The Deep'. Again, a mastering job that distorts the waveform. You can find it here...
https://www.youtube.com/watch?v=0AOhBWNdpHk
Mastering has two major components, EQ and compression. Both should be used to make the original recording sound better.
As we have seen, This almost never happens these days. EQ is a complex issue that requires lots of research (which I have done) but it is a subject that takes too long to cover in a blog. Basically, the EQ is to make sure that the overall sound is balanced with the right amount of highs, lows, and mid-range. Learning what that sounds like requires years of listening to good music, and today's top 40 does not qualify by any stretch of the imagination.
Moving to compression, the track should only be compressed if it has a wildly huge dynamic range. Almost no pop music fits into that category. So, modern music needs virtually no compression. It has usually already been compressed to death. If the EQ is right on the mix, it doesn't need that either. However I find that the tracks these days always need EQ to sound half decent. In other words, not only is the compression messed up, the EQ is also wrong. The songs are compressed and limited to death, and the EQ is usually a problem, especially in the low end. So the modern mastering engineer has just 2 jobs and fails at both of them.
So, can you master your tracks yourself? Yes, you can, but you would have to be sure that your sense of EQ is awfully good. I have found a few people under 40 who have a great sense of tonal balance, but not more than I could count on the fingers of one hand.
During the years when I was working at BMG, I found hundreds of errors that had come through the hands of the biggest names in Mastering. This is only more prevalent today. The technology has increased 10-fold, and the bad music has increased 100-fold. It would seem that the better technology we get, the worse the music gets.
As far as compression goes, you can screw it up as well as the 'pros'. It does not take any talent at all.
You can read my blog entries for the past couple of years if you would like to review the evidence on that front.
EQ is where the expertise comes in, and if you listen to great music of the past, you have a chance to be good at it.
This is a brief overview of what Mastering was and is. If you see the results of the biggest names in Mastering in my blog,
You will probably gain the courage to try it on your own music yourself.
This is the outline of what the music should look like by the numbers.
True Peak level -1 dB
LKFS/LUFS level -16 db
DC Offset 0.000 dB
Clipped Samples 0
RMS level difference for left and right channels less than a dB, or less than .1 dB, or less than .01 dB even better
Equalization curve without obvious flaws
Now you hopefully have a better understanding of what Mastering is and whether you need it or not.
It is a real thing, but it has not been well represented since the mid '90's.
It would be a different ball game if they were required to master to -16 dB LUFS and -1 dB True Peak, but that is only being required on a few platforms, not across the board. Until then, expect poor music, mastered poorly, for poor people who don't know any better.
The loudness difference between these 2 tracks is about 8.3 dB. That means that you need to turn down the second example by that amount to match the first piece. Except that it actually would sound better to turn it down by about 20 dB, but that is a different issue.
In this video I take a look at Adele's 'Rollin' In The Deep'. Again, a mastering job that distorts the waveform. You can find it here...
https://www.youtube.com/watch?v=0AOhBWNdpHk
Mastering has two major components, EQ and compression. Both should be used to make the original recording sound better.
As we have seen, This almost never happens these days. EQ is a complex issue that requires lots of research (which I have done) but it is a subject that takes too long to cover in a blog. Basically, the EQ is to make sure that the overall sound is balanced with the right amount of highs, lows, and mid-range. Learning what that sounds like requires years of listening to good music, and today's top 40 does not qualify by any stretch of the imagination.
Moving to compression, the track should only be compressed if it has a wildly huge dynamic range. Almost no pop music fits into that category. So, modern music needs virtually no compression. It has usually already been compressed to death. If the EQ is right on the mix, it doesn't need that either. However I find that the tracks these days always need EQ to sound half decent. In other words, not only is the compression messed up, the EQ is also wrong. The songs are compressed and limited to death, and the EQ is usually a problem, especially in the low end. So the modern mastering engineer has just 2 jobs and fails at both of them.
So, can you master your tracks yourself? Yes, you can, but you would have to be sure that your sense of EQ is awfully good. I have found a few people under 40 who have a great sense of tonal balance, but not more than I could count on the fingers of one hand.
During the years when I was working at BMG, I found hundreds of errors that had come through the hands of the biggest names in Mastering. This is only more prevalent today. The technology has increased 10-fold, and the bad music has increased 100-fold. It would seem that the better technology we get, the worse the music gets.
As far as compression goes, you can screw it up as well as the 'pros'. It does not take any talent at all.
You can read my blog entries for the past couple of years if you would like to review the evidence on that front.
EQ is where the expertise comes in, and if you listen to great music of the past, you have a chance to be good at it.
This is a brief overview of what Mastering was and is. If you see the results of the biggest names in Mastering in my blog,
You will probably gain the courage to try it on your own music yourself.
This is the outline of what the music should look like by the numbers.
True Peak level -1 dB
LKFS/LUFS level -16 db
DC Offset 0.000 dB
Clipped Samples 0
RMS level difference for left and right channels less than a dB, or less than .1 dB, or less than .01 dB even better
Equalization curve without obvious flaws
Now you hopefully have a better understanding of what Mastering is and whether you need it or not.
It is a real thing, but it has not been well represented since the mid '90's.
It would be a different ball game if they were required to master to -16 dB LUFS and -1 dB True Peak, but that is only being required on a few platforms, not across the board. Until then, expect poor music, mastered poorly, for poor people who don't know any better.
As we have noted elsewhere on this website, all music (including music destined for vinyl) can fit into the 'LUFS -16 dB, True Peak -1 dB' box, whether it is folk, jazz, rock, classical, big band, singer-songwriter, world, etc. This we have determined by analyzing thousands of tracks from the last 100 years of recorded music. So anything beyond this 15 dB LUFS to peak difference can be said to be compressed in some way. Vinyl was and is a medium that compressed music slightly due to it's physical limitations(This was also true of the magnetic tape that the music was originally recorded on). However, the music of today is compressed not because of limitations of medium, but because of the misguided belief that it will sound louder and thus compete favorably with the other poorly mastered tracks and somehow result in more money in the pockets of those concerned. If 15 dB is the standard for well mastered music tracks, you can easily figure out how much the modern master is overcompressed. If a master comes in at -8 dB LUFS, then it is overcompressed by 8 dB. Since the very worst of mastering jobs results in a figure of about -6 dB, we can extrapolate a range of overcompression of about 10 dB. (-16 perfect, -6 dB horrible)
We can guess with considerable accuracy that -11 dB LUFS is halfway to horrible. In any case,
this gives you a range to expect overcompression just by the LUFS number.
The next problem is the clipped sample issue. If the sample peaks are not carefully and skillfully controlled to a level of -.1 dB to -1 dB, the result will be sample peaks that are digitally clipped (sawed off) by the digital converter that can not have any signal above 100% or 0 dB. The result of the clipped samples is easily seen in a good waveform analyzer, and the number of clipped samples is easily computed by a program such as Izotope's RX. Since the waveform is what determines the sound that eventually comes out of your speakers or headphones, the clipped samples will absolutely affect the quality of the sound as you hear it. You can go through the many examples on this website and see that virtually all of them have clipped samples and therefore unnecessarily compromised sound. Some of them have over 100,000 clipped samples. It boggles the mind.
While we are remembering the reasons for the numbers, let's look at DC offset. DC offset is the degree to which the waveform is centered on the proper 0 axis. All music in the real world will have 0 DC offset, that is, it is exactly the same level on one side of the X axis as the other. Electronic circuits from the microphone to the Digital to Analog Converters can introduce flaws in the circuit that result in a deviation from 0 of up to 1%. The deviation is usually small, but again it is something that affects the waveform and therefor the sound. It is easily fixed, and is certainly something that should be fixed before going out of a mastering facility. If you look at the DC offset of all of the tracks analyzed on this website, you will find that virtually all of them have an offset of some kind. Critical?..no...sloppy?..yes.
Dynamic range is first determined by the music itself. Classical music and movie soundtracks will have very wide dynamic range that can exceed 20 dB. Dance music and overcompressed rock music will have a very small dynamic range that can be as small as 1 dB. Everything else is in between. One of the problems associated with overcompressing for the purpose of electrical loudness, is that the dynamic range of the original performance or recording must be reduced. Since dynamics is one of the most important aspects of a performance or recording, the impact of the music is reduced by any overcompression. The more the overcompression, the more the music suffers as a result. The -16 dB range is sufficient for every style of music; especially considering the low noise floor that digital production offers. Even though live performances can exceed the dynamic range that the -16 dB range requires, the music still has enough dynamic range to satisfy the most discriminating audience.
The last item that we analyze for this website is the balance of left and right channels. The smaller the difference, the better. This is especially true when most of the listening will be done with earbuds or headphones. I like to keep it within .01 dB. Again, critical?..no...sloppy?..yes.
Probably the most important aspect of mastering is the equalization of the track which determines how it will sound to the average listener in a wide variety of listening environments. It needs to sound good on earbuds, cheap headphones, expensive headphones, cheap loudspeakers, and expensive audiophile systems. Over the decades of recorded sound, we have figured out what sorts of compromises are needed to portray the performance accurately and also fit within the limitations of the medium.
For instance, the 1812 Overture by Tchaikovsky is a work that calls for cannon fire in the final climax. That noise is so loud that it is not possible for recording mediums and loudspeakers to accurately reproduce. But we can approach the effect and not destroy our speakers by carefully tailoring the EQ to mimic the sound. A real cannon has a concussive impact below 20 Hz. Our speakers can not do that without lasting damage. So we have to cut off everything below 20 Hz to save our equipment. On the upper end of the frequency spectrum, live sounds can have frequencies from 50 to 100 kHz. But our ears cannot hear them and most of our equipment cannot play them, so it is not prudent to try to include them.
Over the last century, the audible frequency spectrum is considered to be 20 to 20 kHz. All of reasonable music will fit into this range. Our equipment for reproducing and listening to music is also capable of handling this range. So the important range to consider is a maximum of 20 Hz to 20 kHz.
Average hearing range is actually less than that. Average hearing range is from 30 Hz to about 15 kHz. So that is much more important as a frequency spectrum to consider. Also, average listening equipment will struggle to reproduce sounds below 30 Hz and sounds above 15 kHz. If a speaker is struggling to reproduce a sound that is below 30 Hz, it will distort the sound and will often distort other frequencies as well. So trying to deliver frequencies beyond the ability of playback systems does not enhance the quality of the sound at all. What is important is the balance of the frequencies within that 30 Hz to 15 kHz window. That is what determines how the music sounds. That is what really separates the good from the bad.
We have demonstrated how sloppy mastering will adversely affect the quality of the sound. But EQ is the most important aspect of the mastering process. Fortunately, there are many sophisticated software tools that can aid us in figuring out what is good and bad EQ or frequency spectrum level. I have had the advantage of having access to thousands of masters and the most sophisticated of analysis software. However, you can do the same thing at home to a similar extent.
A CD is identical to the 1630 master or digital file master and so is just as effective. You can use a good frequency analysis software tool to analyze each song or part of a song to see what the EQ curve looks like. You will see that in all of the tracks that I have analyzed on this site. After a while you will notice that all great sounding recordings have the same kind of curve. This is true of great recordings made in the 50s to great recordings made today. After becoming familiar with many great recordings, you will be able to spot problems in masters that are not as well done, and learn to hear the problems you see on the frequency spectrum analysis.
I have not gotten into this on this website because this is deep and complex. It is simple and above argument to show the numbers that result from simple analysis. The EQ curve is the most important factor that determines good mastering. I could go through and explain the problems in each of the masters analyzed here in the past 3 years, but that would take a lot of time and explanation. What I will say is that if you look at the EQ curves on these pages, they are all similar (that is good), but they all have bumps and cuts that the great masters of the past do not have (that is bad). If you study just the tracks that are on this website, you can learn an awful lot about proper EQ curves. If you listen to the track, try to identify the problems, then check the EQ and see where the curve correlates to the problem. The only thing left is to learn what good music sounds like. That is something that you have to determine for yourself. Not everyone will agree on everything. But there are standards that most everyone will agree on. And they are standards because they are so good.
In the modern era, here are some examples of great music recordings...
1976 George Benson Breezin'
1976 Eagles Greatest Hits
1979 Bob Dylan Slow Train Comin'
1980 Grover Washington Jr. Winelight
1982 Michael Jackson Thriller
1996 George Benson That's Right
There are many great sounding records out there, but they are still a definite minority in the universe of recorded music.
The more you listen to good music, the quicker you will be able to recognize poorly mastered music.
A fun practice is to take a song (such as any of the ones analyzed here in the past 3 years)
and take it apart and see if you can fix all the flaws.
Practice makes perfect.
We can guess with considerable accuracy that -11 dB LUFS is halfway to horrible. In any case,
this gives you a range to expect overcompression just by the LUFS number.
The next problem is the clipped sample issue. If the sample peaks are not carefully and skillfully controlled to a level of -.1 dB to -1 dB, the result will be sample peaks that are digitally clipped (sawed off) by the digital converter that can not have any signal above 100% or 0 dB. The result of the clipped samples is easily seen in a good waveform analyzer, and the number of clipped samples is easily computed by a program such as Izotope's RX. Since the waveform is what determines the sound that eventually comes out of your speakers or headphones, the clipped samples will absolutely affect the quality of the sound as you hear it. You can go through the many examples on this website and see that virtually all of them have clipped samples and therefore unnecessarily compromised sound. Some of them have over 100,000 clipped samples. It boggles the mind.
While we are remembering the reasons for the numbers, let's look at DC offset. DC offset is the degree to which the waveform is centered on the proper 0 axis. All music in the real world will have 0 DC offset, that is, it is exactly the same level on one side of the X axis as the other. Electronic circuits from the microphone to the Digital to Analog Converters can introduce flaws in the circuit that result in a deviation from 0 of up to 1%. The deviation is usually small, but again it is something that affects the waveform and therefor the sound. It is easily fixed, and is certainly something that should be fixed before going out of a mastering facility. If you look at the DC offset of all of the tracks analyzed on this website, you will find that virtually all of them have an offset of some kind. Critical?..no...sloppy?..yes.
Dynamic range is first determined by the music itself. Classical music and movie soundtracks will have very wide dynamic range that can exceed 20 dB. Dance music and overcompressed rock music will have a very small dynamic range that can be as small as 1 dB. Everything else is in between. One of the problems associated with overcompressing for the purpose of electrical loudness, is that the dynamic range of the original performance or recording must be reduced. Since dynamics is one of the most important aspects of a performance or recording, the impact of the music is reduced by any overcompression. The more the overcompression, the more the music suffers as a result. The -16 dB range is sufficient for every style of music; especially considering the low noise floor that digital production offers. Even though live performances can exceed the dynamic range that the -16 dB range requires, the music still has enough dynamic range to satisfy the most discriminating audience.
The last item that we analyze for this website is the balance of left and right channels. The smaller the difference, the better. This is especially true when most of the listening will be done with earbuds or headphones. I like to keep it within .01 dB. Again, critical?..no...sloppy?..yes.
Probably the most important aspect of mastering is the equalization of the track which determines how it will sound to the average listener in a wide variety of listening environments. It needs to sound good on earbuds, cheap headphones, expensive headphones, cheap loudspeakers, and expensive audiophile systems. Over the decades of recorded sound, we have figured out what sorts of compromises are needed to portray the performance accurately and also fit within the limitations of the medium.
For instance, the 1812 Overture by Tchaikovsky is a work that calls for cannon fire in the final climax. That noise is so loud that it is not possible for recording mediums and loudspeakers to accurately reproduce. But we can approach the effect and not destroy our speakers by carefully tailoring the EQ to mimic the sound. A real cannon has a concussive impact below 20 Hz. Our speakers can not do that without lasting damage. So we have to cut off everything below 20 Hz to save our equipment. On the upper end of the frequency spectrum, live sounds can have frequencies from 50 to 100 kHz. But our ears cannot hear them and most of our equipment cannot play them, so it is not prudent to try to include them.
Over the last century, the audible frequency spectrum is considered to be 20 to 20 kHz. All of reasonable music will fit into this range. Our equipment for reproducing and listening to music is also capable of handling this range. So the important range to consider is a maximum of 20 Hz to 20 kHz.
Average hearing range is actually less than that. Average hearing range is from 30 Hz to about 15 kHz. So that is much more important as a frequency spectrum to consider. Also, average listening equipment will struggle to reproduce sounds below 30 Hz and sounds above 15 kHz. If a speaker is struggling to reproduce a sound that is below 30 Hz, it will distort the sound and will often distort other frequencies as well. So trying to deliver frequencies beyond the ability of playback systems does not enhance the quality of the sound at all. What is important is the balance of the frequencies within that 30 Hz to 15 kHz window. That is what determines how the music sounds. That is what really separates the good from the bad.
We have demonstrated how sloppy mastering will adversely affect the quality of the sound. But EQ is the most important aspect of the mastering process. Fortunately, there are many sophisticated software tools that can aid us in figuring out what is good and bad EQ or frequency spectrum level. I have had the advantage of having access to thousands of masters and the most sophisticated of analysis software. However, you can do the same thing at home to a similar extent.
A CD is identical to the 1630 master or digital file master and so is just as effective. You can use a good frequency analysis software tool to analyze each song or part of a song to see what the EQ curve looks like. You will see that in all of the tracks that I have analyzed on this site. After a while you will notice that all great sounding recordings have the same kind of curve. This is true of great recordings made in the 50s to great recordings made today. After becoming familiar with many great recordings, you will be able to spot problems in masters that are not as well done, and learn to hear the problems you see on the frequency spectrum analysis.
I have not gotten into this on this website because this is deep and complex. It is simple and above argument to show the numbers that result from simple analysis. The EQ curve is the most important factor that determines good mastering. I could go through and explain the problems in each of the masters analyzed here in the past 3 years, but that would take a lot of time and explanation. What I will say is that if you look at the EQ curves on these pages, they are all similar (that is good), but they all have bumps and cuts that the great masters of the past do not have (that is bad). If you study just the tracks that are on this website, you can learn an awful lot about proper EQ curves. If you listen to the track, try to identify the problems, then check the EQ and see where the curve correlates to the problem. The only thing left is to learn what good music sounds like. That is something that you have to determine for yourself. Not everyone will agree on everything. But there are standards that most everyone will agree on. And they are standards because they are so good.
In the modern era, here are some examples of great music recordings...
1976 George Benson Breezin'
1976 Eagles Greatest Hits
1979 Bob Dylan Slow Train Comin'
1980 Grover Washington Jr. Winelight
1982 Michael Jackson Thriller
1996 George Benson That's Right
There are many great sounding records out there, but they are still a definite minority in the universe of recorded music.
The more you listen to good music, the quicker you will be able to recognize poorly mastered music.
A fun practice is to take a song (such as any of the ones analyzed here in the past 3 years)
and take it apart and see if you can fix all the flaws.
Practice makes perfect.
