Now to the fun part. Let's trace the signal through a Legato Link player:-
The signals from the laser pickup come along the grey ribbon cable on the left and are fed to a
Sony CXA1372S (pdf) RF signal processor and sled/tracking/focus servo driver chip (the big one at the bottom). To the right of that and mostly hidden undder the board is a surface mount chip which presumably decodes the disc data to PCM and applies the CIRC error correction. From there it's on to the top level via a 15-wire ribbon cable (at the right) to a Pioneer PD0116A chip which I think is just a multiplexer breaking out the left and right channel digital info.
The two
PULSEFLOW Pioneer PD2028B single-bit DAC's are the medium sized chips symmetrically placed with a 74HCU04 Toshiba chip inbetween them providing some logical glue. Behind it is the timing crystal. The differential outputs of the Pulseflow chips go to
JRC 5532DD op-amps which are surrounded by analog filter components, and also appear to be getting some buffer assistance from 6 transistors per channel (three C3068's, two C124's and an A124). Output impedance is fairly low, 100 ohms or so with enough oomph to drive a pair of high impedance headphones.
Voltage regulators abound. Top left are the +/-12V pair. Behind the crystal (centre) is a pair of 5V reg's, must be one for each DAC. To the left is another 5V reg, presumably for the multiplexer.
If you buy a cheaper (non-Legato-Link) version you don't get the upper analog board at all, and all the empty real estate on the lower board will be filled up, probably with a single multi-bit DAC.