One of the more dangerous things in this world is a man with extra time and extra money. A danger to himself and to the world at large. If it’s not an actual, you know, danger, then it’s just stupidity – a different kind of danger. Semantics aside, I have some extra time and some extra money and wanted to get an answer on something. With the entire knowledge and experience of the Internet failing me, or at least failing to convince me, I set out to get my own answer. Am I going to change the world with my soon-to-be-found knowledge? Fuck, no. It’s so trivial, it hardly even matters to anyone.
To even appreciate what I am seeking, you have to be pretty involved in my hobby of CD collecting. If you’re not, then the rest of this post won’t even really interest you. Further, you have to be fairly experienced with technology and computers, otherwise, this won’t really make much sense. So, warnings provided, now for the explanation.
In the early days of CD manufacturing, some CDs were pressed with “pre-emphasis”, which is a special equalization. CD players as part of their manufacturing specification had to be able to detect pre-emphasis and apply a reverse equalization (de-emphasis) when playing back these early CDs. Sounds pretty simple, right? Over time (actually very quickly), pre-emphasis use was discontinued, so all CDs today don’t have pre-emphasis anymore. That’s fine for the general public, but somewhat of a nuisance for early CD collectors like myself.
Now that you understand the situation, here is the problem in a nutshell: CD players – and especially computer CD-ROMs – do not have the capability to detect pre-emphasis anymore. So if you play back an early CD, you do not get the corrective equalization applied to the music, which makes it sound thin and harsh. This also applies to CDs that you rip on your computer. There are software plug-ins that can apply de-emphasis to the files after they have been ripped, so the problem can be somewhat mitigated. But aside from using your ears, because the CD-ROM cannot detect the pre-emphasis, you can’t know for sure if the CD you ripped has pre-emphasis. Again, not a problem for anyone but early CD collectors.
And so what I am looking to know is: I want to be able to detect pre-emphasis on CDs in my computer. Thus, my project.
I’ve discussed the CD history, now for the computer history. Early computer CD-ROM were literally mini-cd-players. They had a headphone jack and a volume control and some even had a play button in addition to the eject button. Additionally, on the back of the drive, there was a jack to run the audio from the CD drive to the computer’s sound card. These old drives played audio CDs in analog. They had build in DACs (digital-to-analog converters), but you can be pretty certain they were not of the quality found in home stereo CD players. Still, because they were doing the digital conversion, they also had to support handling pre-emphasis.
As technology moved on, pre-emphasis was no longer a concern and also, Windows began reading the audio from CDs digitally. So drive makers dropped the headphone jack, dropped the DACs and dropped analog output completely. It made the devices cheaper and audio could be read at the drive’s full speed instead of the 1X speed of analog. Technologically, a great step forward. But in the process of simplifying the device, they removed the capability to read pre-emphasis at all – it wasn’t needed.
But now, I want to get an old CD-ROM that has a DAC and analog output so I can hopefully detect pre-emphasis when ripping a CD. The problem is that all those old drives use the IDE interface, which is long, long obsolete. Computers now use the SATA interface. But that’s only a stumbling block because of course someone has made an IDE-SATA interface converter. So, technically, everything is still possible. I don’t have to go to the extreme of building an old Pentium computer from parts salvaged from the 90s, thank god.
Naturally, EBay is the order of the day. Because this project is only for curiosity, I’m buying stuff as cheap as possible. For $16, I have a 19-yr old CD-ROM and an interface kit coming by next week. Then it will be a challenge to see if I can get my computer to see the new (old) drive, then it will be a challenge to see if the ripping software will talk to the new (old) drive, and if it does, will the drive report the pre-emphasis information to the software.
So, there’s still some unknowns. For the $16 I’ve spent, I’ve purchased a lottery ticket for either frustration or a jackpot of, “oh, neat.” What will I do with this incredible information? Well, obviously, I’ll share it whenever I can. It will be a good data point for my posts on Relative Waves and I’m sure some other collectors would like to know which CDs have pre-emphasis.
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