Is it common/allowed that the voltages differs in dual voltage systems?
I was going to rip the complete power system (those parts used for RIAA stage) from Technich SA-210 but, I'm not sure if it's in good condition because of difference in DC voltage between +V/-V (+17.8V/-15.4V). There are differences in components starting from R703/R707 which are not equal but those different components does not make the voltages even (measured from the legs of the NJ4559 found in EQ where the leads end). Voltages before these resistors are equal.
My intention is to use this power 'stage' in a RIAA stage (based on op-amps) project ... if it's in condition.
I was going to rip the complete power system (those parts used for RIAA stage) from Technich SA-210 but, I'm not sure if it's in good condition because of difference in DC voltage between +V/-V (+17.8V/-15.4V). There are differences in components starting from R703/R707 which are not equal but those different components does not make the voltages even (measured from the legs of the NJ4559 found in EQ where the leads end). Voltages before these resistors are equal.
My intention is to use this power 'stage' in a RIAA stage (based on op-amps) project ... if it's in condition.
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Original schematic (as PDF) can be found through that link given in my 1st post (you find all possible information from it, component types/values etc.).
EDIT: I'm going to remove R712 because of I don't need that circuit but, is the circuit (or parts of it) where R708 leads needed (it is lower voltage circuit) ... ?
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Ok.
Those sites are sometimes confusing (there are unnecessary (3rd party) links you can go wrong with). I changed the link to point directly to PDF file but, in any case here's the necessary part of the circuit (If the image doesn't show up right away just press the down arrow button (on top left) to load/open it. Blue lines seen in picture shows positions I have cut the leads because of I don't need those circuits.
Those sites are sometimes confusing (there are unnecessary (3rd party) links you can go wrong with). I changed the link to point directly to PDF file but, in any case here's the necessary part of the circuit (If the image doesn't show up right away just press the down arrow button (on top left) to load/open it. Blue lines seen in picture shows positions I have cut the leads because of I don't need those circuits.
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Thanks 
Looking at your picture D703/704 are different values by design... I have no idea why though. Maybe to give some better controlled start up or switch off performance (thumps and bang), just a guess though.
I doubt there is any problem with the circuitry. Measuring across the zeners directly should give a voltage equal to the zener value -/+ 10, so your values seem a little out. Again, maybe the zener values used are different to what is marked on the diagram. Manufacturers do change designs and sometimes there are quite significant differences between models intended for different destinations.
Looking at your picture D703/704 are different values by design... I have no idea why though. Maybe to give some better controlled start up or switch off performance (thumps and bang), just a guess though.
I doubt there is any problem with the circuitry. Measuring across the zeners directly should give a voltage equal to the zener value -/+ 10, so your values seem a little out. Again, maybe the zener values used are different to what is marked on the diagram. Manufacturers do change designs and sometimes there are quite significant differences between models intended for different destinations.
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