Why don’t all CD players sound the same?

They’re just not going to, any more than amplifiers, speakers or guitars will sound the same because the sonic end result is the sum of many elements working together.

A common technical misunderstanding is that:

“It’s all just ones and zeros.”

If it were just ones and zeros, there’s a good chance all CD players would sound the same, or similar at least. But it isn’t. You can’t listen to those ones and zeros, a lot has to happen before we can hear them. Yet again we see technical misunderstandings, fuelled by misinformation.

The sound heard from a CD player is significantly influenced by each of the following:

  • CD mechanics and laser
  • DAC type and design – R2R/multibit delta-sigma/chip/discrete – the ones and zeros part
  • Analog and digital filter type and design – HDCD/FPGA/DSP…
  • Inter-stage analog buffers
  • Output buffer – chip/discrete/class-A/tube/transistor/transformer/balanced/singled-ended etc
  • Power supply – linear/SMPS/rails/filtering
  • Clock – frequency/PPM precision/drift
  • General parts type and quality
  • Layout, board design, wiring, shielding
  • Condition of the unit, laser power output

Every element influences what you hear. The ones and zeros part is actually a small part of the complete CD player.