Help- I changed P.S Caps in Pre-amp, strange voltages resulted

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I renewed several electrolytics along the P.S rails in a Meridian 201 pre-amp, the amp would not work afterward. I have gone back and desoldered the caps, still no sign of the fault.
Measurements-
A rectifier feeds plus and minus 20v to the two regulators, where I measured the following voltages-
LM337
Neg 16.5V Out Pin
Neg 18.00V In Pin
Neg 16.50V Adj Pin
LM317
Pos 19.80V Adj Pin
Pos 19.80V Out Pin
Pos 20.00V IN Pin
Here's the scarey bit- further down the positive rail towards the audio circuits,the voltage coming out of the LM317 changed from 19.80V to Negative 5.5V!(There is no component close to this point that I could take out). I also heard only switching noises coming out of the preamp's outputs, and the voltage meter showed a Negative 5.5V of DC on the signal connections! Can anyone postulate how this fault could have come about. I have been up and down the board visually looking for solder splatters etc. but can't see any, nor find a short anywhere on the P.S rails. Where should I go next, and is my pre-amp now toast? Any informed help appreciated folks,
HUgh

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Topic - Help- I changed P.S Caps in Pre-amp, strange voltages resulted - hugh 10:32:33 01/08/01 (1)

Re: Help- I changed P.S Caps in Pre-amp, strange voltages resulted - bobwire 15:20:59 01/08/01 (0)

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