Modifying Pioneer DV-355 DVD Player

Pioneer DV-355 DVD Player, 2004-2005 model for outside Japan. BB PCM1742 DAC and JRC NJM4560 buffer.

Thru my mods on DV-600AV to improve sound quality, I found #1 weakness of stock Pioneer is in its thin lines of internal power supply connection, from PS board to main board. I had already made slight mods on my DV-355 just after I bought this in Seoul/South Korea, such like replacing stock caps by BlackGate, or replacing JRC4560 by AD8620. Here I made some additional mods, including PS re-wiring.

PS connector on PS board. This is the thirteen pins connector with #1 is assigned for white wire. #9 is +12V and #12 is GND for analog signal. On the PS PCB, +12V line appears onto the surface at the jumper J102 right next to the connector, and GND appears at J106, below the transformer in this picture.

I cut #9 here and re-wired +12V line directly from J102 by white lead wire. I left original GND lines in the connector as they were, and wired additional GND line from J106 by green lead wire. In addition, I replaced stock main cap, Nippon-Chemicon KMQ 400V/68uF with KMG 350V/100uF, and added small OS-con at the pattern for decoupling +12V line, where no cap installed in the original state.

Install white +12V line at the vacant pattern for some optional connector, green GND line at the vacant pattern for some optional grounding. Blue grey caps are stock ones, brown larger caps are my installation, replacing stock caps or newly placing 10uF at the vacant cap patterns. Not sure about the effect of these replacement ;-)

To maintain and keep my soldering ability, I replaced the opamp once again. This time from AD8620 to OPA2604, justifying myself that the taste of 2604 might be better than AD8620 for movie sound. Four BlackGates here are coupling caps for input/output opamp. My personal belief is that BlackGate is the cap for coupling, not for decoupling.

During my try and errors, I tested this kind of stuff at the PS wires. It really spoiled the sound reproduction, made the sound no-detail, no-air. Not recommended at all.

End of mods. Sound became great, with deep massive bass. Not sure if it comes from 350V/100uF mains cap on PS board, strengthened PS wires, or OPA2604, though, I can hear really beautiful movie sound. On this movie-familiar bass sound, modded DV-355 is clearly superior than my modded DV-600AV, which is with external PS and with additional transistor buffer at the opamp output.

My mods story on DV-600AV is here, in Japanese, but with many pictures.