Friends, who can tell me what caused such a wild shunting of the amplifier for the German market? Are these such requirements? Or is it a "correction" for German hearing? Look at the diagram, IMHO, the removal of a heap of containers (indicated by the letter G in the diagram) should have a positive effect on the sound. Any opinions?
These are caused by the rather extreme "FTZ" (Fernmeldetechnisches Zentralamt) regulations in Germany in the 80ties to prevent radio interference. This, for example, led to way to high input capacitances on the phono inputs. They certainly filtered out radio frequencies but parts of your music as well.
Though FTZ was a tad too much some of those caps better stay there (like C102, C103, C425). Today RF is all around you and the caps might be the exact right solution for that.
RC filtering is a blessing and not a curse but better use film capacitors and not ceramic ones. At amplifier inputs calculate for 100....150 kHz cutting frequency.
RC filtering is a blessing and not a curse but better use film capacitors and not ceramic ones. At amplifier inputs calculate for 100....150 kHz cutting frequency.
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These capacitors are of the pF order and have no effect on the sound. This is some psychosis with these capacitors basically connecting the housing with the ground of the amplifier.
Firstly, they protect against excitation of the amplifier at high frequencies.
Secondly, in 30-year-old devices, NIpoon Chemi-Con AVF series capacitors dry out, they can cause changes in the sound, certainly not 100pF ceramics (unless it has a short circuit, but this is unlikely to happen).
Sony often develops cold solder joints after such a period of time; the lack of good contact in some parts of the circuit not only degrades the sound but may also damage the amplifier.
These capacitors should not be removed, they have no effect on the sound.
Firstly, they protect against excitation of the amplifier at high frequencies.
Secondly, in 30-year-old devices, NIpoon Chemi-Con AVF series capacitors dry out, they can cause changes in the sound, certainly not 100pF ceramics (unless it has a short circuit, but this is unlikely to happen).
Sony often develops cold solder joints after such a period of time; the lack of good contact in some parts of the circuit not only degrades the sound but may also damage the amplifier.
These capacitors should not be removed, they have no effect on the sound.