Shopping for a CD player usually means reading about the DAC chip. That is understandable, because the digital-to-analog converter is the part that turns numbers into a voltage. But the chip does not connect directly to your amplifier. Between the DAC and the output jacks sits the analog output stage, and it has as much influence on the final sound as the converter itself.<\/p>\n
A CD stores audio as 16-bit samples at 44.1 kHz. The transport reads those samples, the DAC converts them into a small analog current, and the output stage turns that current into a usable voltage. Along the way, the stage filters out high-frequency noise, sets the output level, and buffers the signal so it can drive a cable and an amplifier without losing strength.<\/p>\n
Many DAC chips output a current rather than a voltage. The first job of the output stage is to convert that current into a voltage, usually with an operational amplifier and a feedback network. The quality of this stage affects noise and linearity.<\/p>\n
Digital audio carries ultrasonic noise above the audible band. A low-pass filter removes it before it reaches the amplifier, where it could cause distortion or heat. The filter design also affects phase behavior near the top of the audible range. For more on that topic, see our explanation of sharp versus slow digital filters<\/a>.<\/p>\n Budget players typically use one or two op-amp chips per channel. Better players may use discrete transistor circuits, which cost more and take up more board space but can offer lower distortion and more output current. Neither approach is automatically superior; implementation matters more than the part type.<\/p>\n The output stage needs clean DC power. A well-designed player separates the digital and analog supplies, uses local regulation near the audio circuits, and chooses capacitors that suit the circuit. Cheap players often share one noisy supply across the whole board, which can add hum or grain.<\/p>\n Two players can use the same converter chip and still sound different because the output stage, clocking, power supply, and board layout are all different. A converter is only as good as the analog circuitry around it. This is also why a cheap player with a famous DAC chip does not automatically beat a well-built player with a modest chip.<\/p>\n It is easy to overstate the audible difference between output stages. In a level-matched blind test, two competent players often sound very close. The differences that do survive are usually about noise, channel balance, and how the player behaves with demanding material. A noisy output stage is audible as hiss or hum; a weak one can sound thin with long cables.<\/p>\n If you are shopping, look for a player with a solid chassis, a proper analog board, and a fixed line output. Do not pay a premium for a converter chip alone. If you plan to use an external DAC, a transport is the more sensible purchase, and our article on what a CD transport is<\/a> explains the difference. Otherwise, choose a player whose output stage is matched to the rest of your system. Perladar’s CD players are built around exactly this balance.<\/p>","protected":false},"excerpt":{"rendered":" The DAC gets all the attention, but the analog output stage shapes what you actually hear. Here is what it does and which parts are worth caring about.<\/p>","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[1323,1193,81],"_links":{"self":[{"href":"https:\/\/perladar.com\/ja\/wp-json\/wp\/v2\/posts\/64322"}],"collection":[{"href":"https:\/\/perladar.com\/ja\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/perladar.com\/ja\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/perladar.com\/ja\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/perladar.com\/ja\/wp-json\/wp\/v2\/comments?post=64322"}],"version-history":[{"count":1,"href":"https:\/\/perladar.com\/ja\/wp-json\/wp\/v2\/posts\/64322\/revisions"}],"predecessor-version":[{"id":64336,"href":"https:\/\/perladar.com\/ja\/wp-json\/wp\/v2\/posts\/64322\/revisions\/64336"}],"wp:attachment":[{"href":"https:\/\/perladar.com\/ja\/wp-json\/wp\/v2\/media?parent=64322"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/perladar.com\/ja\/wp-json\/wp\/v2\/categories?post=64322"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/perladar.com\/ja\/wp-json\/wp\/v2\/tags?post=64322"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}Op-amps or discrete circuits<\/h3>\n
Capacitors and power supply<\/h3>\n
Why Two Players With the Same DAC Sound Different<\/h2>\n
Specs That Actually Matter<\/h2>\n
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What You Can and Cannot Hear<\/h2>\n
Buying Advice<\/h2>\n