Nice to know the good ones. Although according to the jung article the lm317 was not as bad as the lm337 and could even be recommended for some designs.
I hear generally nice things about micrel regulators. Have they better ones for audio?
Micrel as far as I can see has nothing advantageous for audio. One of the issues with audio is that the power supply rails tend to be > +/-12V and Micrel has most of its devices in a lower voltage process (5V) so that greatly limits the choices. I did find a few of their higher voltage devices but the one I looked at didn't even show a plot of rejection vs frequency, which tells me its BAD. Looking at it's schematic, it also has a single pass transistor output so I expect it to be bad in this regard. They do have something called a ripple blocker power filter but it looks like it's for low voltage digital devices (like powering FPGA's, uP, uC etc..) Maybe Micrel has good cost going for them, I dont see it.
The ripple rejection issue is an analog problem and Micrel isn't known for being good at analog. Stick with TI, Linear, ADI etc.. or roll your own for these types of designs.