Today, we’re going to find out if buying a pricey CD transport is worth the money. Something tells me, it’s not, but let’s not jump to conclusions, yet. At least not until I do some tests and measurements.
Sony SCD-1
Firstly, what is a CD transport and what does it do? A CD transport should do one thing and one thing only, transport digital data from a CD to a DAC, nothing less nothing more. DAC stands for digital to analogue converter and is used to translate a digital signal that’s coming out of the CD transport to an analogue signal. You can either have a stand-alone CD transport which needs some sort of external DAC or a CD transport can be bundled with a DAC, and that’s called a CD player. Now, the question is, if a CD transport only transports digital data, why don’t people use a simple CD-ROM drive in a computer or a cheap Chinese crap for £5 instead of some high-end transport for £5000. Well, to be brutally honest, I have no idea and that’s the reason why I’m here today. I want to find out if a cheap CD deck or a simple CD or DVD or BluRay or whatever’s inside my PC rig, can do the same thing as an expensive CD transport or any CD transport for that matter. CD transports can get quite expensive and there are couple of factors that can affect the final price.
First. Higher quality optics and laser, that can last longer and read better some scratched or slightly damaged CDs or even ability to read CD-Rs or CD-RWs.
Second. Better error correction. If some part of a CD gets too damaged and unreadable the CD transport will attempt to correct the error to some extent.
Third. Better damping. If you live for example in Japan and you want to listen to CDs during earthquakes, you need a good damping, so your CD transport can withstand those vibrations and keep reading the disk without interruption. But, it’s certainly not necessary under normal conditions.
Fourth. Larger buffer. Every CD transport or CD player’s got some sort of buffer, where it stores data. It plays the music from this buffer rather than directly from the CD, and there’s a pretty good reason for that. If the player encounters some sort of problem, such as vibrations, it won’t affect the playback, unless it keeps misreading large chunks of a CD and buffer can’t keep up.
Fifth. The quality of used materials and components. I don’t need to explain this one, do I?
Sixth. Different types of output. Some cheaper CD transports have only optical and coaxial outputs, also called S/PDIF. Generally, the more expensive the transport gets, the more types of output you can find there.
Seventh. Better shielding against some external interferences, as well as internal.
Eighth. A design. Some companies may charge extra for a sleeker look. At least they may think it’s sleeker.
Test
I’m going to do a simple test. The setup for this test is my two computers, and two CD players. Firstly, I’m going to rip a track from a CD using my internal Blu-ray drive in my PC, then I’m going to record the same track using one of the CD players connected through an optical cable to my computer, which bypasses the internal DAC of the CD player. Why optical cable you ask? It’s a digital transfer and thus bypasses internal player’s DAC and since it’s optical, it’s not prone to electrical interferences. After that I’m going to compare the recorded files in a program called DeltaWave and find out if the tracks are different in any way and if there is some audible difference. If the CD transport does what it’s supposed to do, which is transporting the original and unchanged data, there is no way it should sound any different compared to an internal CD-ROM or any other CD transport. Now to the test.
Sony SCD-1
The CD-ROM in the computer should rip the track perfectly, bit by bit. This way I get perfect copy of the track. To make sure it’s done properly, I used two different CD-ROM drives to rip the track, two different computers, two different operating systems, completely different software to do that and compared these two files for changes in DeltaWave if there were some differences. DeltaWave compares two sound samples for even slightest differences, and spits out some results. The results say, there is no difference, both tracks were exactly the same, we’re off to a good start. Then I connected the SONY SCD-1 to my DAC, which is supposed to be one of the best CD players there is, recorded the same track and compared those tracks in DeltaWave. There is a slight difference in the region around -120dB, which is well below capabilities of human hearing. The music itself hasn’t been changed in any way.
I naturally wanted to know what had caused this difference, so I used the DAC to record a nothing/silence and checked it in DeltaWave. I have found the same difference, which means only one thing, these measured differences are some sort of noise made during the recording by my computer, but the music itself is exactly the same without any audible changes. I tried exactly the same procedure with the Yamaha CD player and the results were exactly the same. Audiophile bollocks like “I’ve heard better bass” or “it’s got better soundstage and micro details” are exactly that, bollocks. The transport is just sending ones and zeros to a DAC which then converts the stream of bits to an analogue sound, which people can then hear. Sure, some data can get lost during the playback for various reasons. Optical cable being too long, coaxial cable getting too much interference, CD being dirty, etc. But the CDs have got some level of error correction, and it helps a lot and if more data is lost than it’s able to correct, it won’t degrade audio quality progressively, neither you’ll notice subtle changes. It works the pretty much the same way as a digital TV. If some data get lost, it doesn’t magically lower the screen resolution, it just corrupts parts of the screen, which correspond to the missing data from the stream. As for the digital audio, you won’t just hear less bass or worse stereo separation or something like that, it will be just nonsense that the DAC made up based on the broken stream, usually pops, clicks and similar sounds. Or in best case scenario, it’s going to be silent.
Sony SCD-1
Conclusion
However high the price can be, the only justification for that is built quality. Whether it costs £5 or £5 000 000, whether it’s a CD transport or a simple CD-ROM in your laptop, it still produces the same stream of bits and there is absolutely no audible difference between them. Unless it’s doing something it’s not supposed to. What makes the difference is a DAC the transport is connected to, so if you want to improve performance of your audio system, do it by getting better DAC, expensive transport is not going to do it. Don’t waste your money on something that’s primarily made for just spinning CDs. Nobody needs a CD transport for £5000 or even £500 unless you don’t care about the money and you just fancy the most expensive thing there is. Selling this stuff for that kind of money is a scam and a rip off. Some people even suggest, that changing a clamp or a weight changes the sound quality, that’s of course, complete bollocks. Don’t fall for this shit and get whatever is cheapest or whatever you fancy, it doesn’t matter.
