Denon Dcd-3560 & Sony Cdp-x77es Mods

[xtaltech]

Hi Everyone,

I bought my Denon DCD-3560 CD player about 18 years. I was satisfied with its performance until one day in the winter of 1995. That year we had many snow storms. Most people would stay home. My only entertainment was listen to music. I only watched TV for the weather report. A friend who lived not far away had a suggestion. He brought his CD player, a Sony CDP-X77ES, for comparison. He had upgraded the OpAmps to OPA2604, as long as I could remember the part number. We found that the Denon was better at the low frequencies while the Sony was very sophisticate in the highs.

Since then, we bought and exchange numerous OpAmps in order to outperform the other. It was fun. Later on, we focused on the filter and decoupling caps. We conducted blind listening tests on the two CD players with different components installed. I registered the numbers and preferences over a period of about six months in order to draw a conclusion on which was the better CD player, which was the best OpAmp, and how this cap sounded more natural over brand B etc... However, the result was inconclusive. Partly due to the limited amount of data (only two listeners), and the limitation of my equipment to differentiate the tonality. And partly due to our wishful thinking.

Today, I'm still listening to the same Denon and he is still modifying his Sony. As we have some electronics background, we would like to conduct objective tests on the OpAmps and other components to look into their characters and differences. At this time the equipment we have are oscilloscope, regulated power supply, signal generator, distortion analyzer and DMM.

Can anyone kindly provide me with some method and knowledge so that I can test the OpAmps and caps off the bench? In such a way that the best component can be selected.

Any suggestion is welcome.

Thanks,
xtaltech

[wsjoe]

I am starting up mod my Denon DCD-3560. I will remove almost all opamps like the 5532, 5534, 4570 and replace with OPA-627. I may have some room problem with the 4570 as this is a dual and fitting two OPA627 with an adapter will be difficult without repositioning that blue capacitor.

What eparts did you mod other than the opamps and did you change any caps? I was surprised to see that the capacitors C538, C539 are not there as shown in the manual.

thanks

[pilli]

...if it's still interesting, and if the schematic I have of the DCD-3560 is correct (I don't have that player, but another "similar" Denon), only one op-amp of the 4570 (which is a dual) is used, for I/V conversion. So you can adapt a single (e.g. OPA627) to the pinout of dual, of course the appropriate half.

(In the DCD-1650 that I have, all the 4570 duals, used for I/V, sum and buffer, have only one op-amp used, go figure... easiest was to replace them with better duals - tried OPA 2604 and OPA2134 - but of course that doesn't exist for the 627...)

On the other hand, both op-amps in the 5532 are used (that's a GIC filter or something like that), so there you'd need to fit two singles indeed.


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