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RE: Question about regulator of Philips CD104

Hi,

The service manual is on-line and you can easily find it.

I am unsure changing the regulator chips is the biggest win in this CDP (and others of similar vintage).

A kep problem is the Digital Filter which creates truly massive amounts of noise on many power supplies, at frequencies that regulates are not effective.

Another problem is an inadequate design of the analogue stage, which exposes a "slow" op-amp to very fast edge rates - a recipe for creating transient intermodulation.

This sort of problem can be resolved by changing the circuit or using faster speed Op-Amp's.

I suspect replacing all electrolytic capacitors (they will have aged well past their useful life), cleaning up the power supplies connected to the Digital Filter using suitable means (in my books a few kuF of Os-Cons and serious Chokes) plus using better suited Op-Amp's (or other circuitry - just check old Audio Amateur etc. issues covering mods to these CDP's) will produce a much better CDP than using fancy regulators and clocks, without fixing fundamental issues.

Thor

At 20 bits, you are on the verge of dynamic range covering fly-farts-at-20-feet to intolerable pain. Really, what more could we need?


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