Been fiddlin' with the dac this afternoon,looking to connect a regulated linear supply to see if it'll improve things.Looking at the mains trannie secondaries,there is a 0-300v to a plastic connector on the pcb,which obviously is the HT for the valve.There is another connector,which has a 0-10v,and also a 9-0-9v supply.There is a bridge rectifier after this and on the other side of this I found 5v dc,to which I connected the linear supply,assuming this is the supply for the dac chip(a cs8414cs).Having disconnected the connector,I fired up the dac and it works,however the gain is less,and on a par in fact with my passived 7510.My question is,I'm guessing one of the secondaries provides this 5v,but what does the other do? Some sort of gain stage? I'm contemplating cutting one of the supplies away from the connector and plugging it back in,but I thought I'd ask first!
Ta.