To mod or not to mod a Sony SCD1

There's only one Dac in the Sony, a PCM 1796.

Mystang,

Aplhifi Which Bur -Brown Dacs are in the Sony?

The service manual lists DSD1796 which is the same as PCM1796.

In my previous post I've mistaken the 5400 with a DVD player. So here is a correction:

The 5400 is not even Panasonic; it is built around a single MediaTek chip (Sony re-labeled) that is found in every $100-200 DVD player (Pioneer, Sony, Oppo, etc.) It is a single-chip-DVD-player processor with HDMI output. The video capabilities are unused in the 5400 but they have PCM and DSD on the HDMI connector. Apart from the fact that this is the most cost-effective single-chip solution available (so the different internal stages interfere with each other), the entire processor runs from a single 27MHz clock reference (that has nothing to do with audio, BTW). Then, inside, there is an extremely jittery PLL to provide clocks for the audio.

Though Sony did a clever job clocking the DAC directly from the 22M audio reference, they are using programmable PLL (75pS jitter) to "convert" 22M to 27M for the MediaTek chip. This results in enormous jitter level coming with the audio data stream to the DAC.

Oh well, what can I say? Blows my mind reading "Sony 5400 the best under $10,000".

Best,
Alex Peychev

Aplhifi Thanks for the detailed description.
Gary

may i ask whether my experience of hiss is related to mod?

this scd-1 come with clock, opa and capacitor mod. before i can appreciate any benefit of this mod. i noticed a hiss by the following: play a cd, stop and crank up the volume. now, a hiss can be heard very easily. i do not feel this is right but have no idea what would be the cause.

i plan to change opa627 back to something more prove(like 5532, tentatively) to see whether it would be quieter.