based on the layout, i would take a very solid guess that it is a split supply, with a positive, negative ang ground, e.g. positive and negative about a the ground, taking a guess from what i see, it is a rather high current one, with a pass transitor of some sort, (havent bothered to google part numbers) and with the 3 diodes, i'm also going to guess it uses and lm317/337 arrangement to offset its bias voltage and allow it to run down to 0V,
the way the second device is arranged, i would also take a guess that its a second pair of the 2 arranged in a current limiter