Alpeh Ono V+ question from service manual

[sianturi]

Could anybody confirm that all the power supply connections circled in red in this attachment (taken from Aleph ONO service manual) are actually connected to the same +30 volts which is connected to pin S of Q3 ?

Thank you

 

[KatieandDad]

In photo 2 it is not possible for the amp to work with Vcc connected to both rails. There has to be a potential difference.

Alephs with a single output device would typically use +/- 24V.

 

[KatieandDad]

30V on the driver stage would ensure that the output stages are fully driven.

 

[sianturi]

On photo #2, okay that should be +30 & -30V then. My bad.

For photo#1 i'm curious why it is not connected at S pin of Q7? Or should it be connected directly to the regulated +30V?

 

[Zen Mod]

everything is fed from regulated 30V rails

why some things are drawn in not-simplest way , Wayne is man to ask

most probably his mental notes , experienced designers (and Wayne is damn experienced) are sometimes drawing schematics already thinking of routing

anyway , no biggie

 

[sianturi]

Okay, sorry for my stupid question.
I finally realized that C12 + R2 + C21 form a CRC filtering after Q9 from the voltage regulator. So the "V+" should be from pin S of Q3 (i.e. the "+" pin of C12)