Bill,
No, it shows how out of date I am!
Seems that many manufacturers have dropped most or all of the 78xx series regulators in favor of more modern designs. Fairchild still has a reasonably complete lineup, though (5, 6, 8, 9, 10, 12, 15, 18, 24) - and they're quite inexpensive at around 3/$1.00 US. You might want to download Fairchild's datasheet just to have for reference.

Seeing the kind of mark-ups our OP has to pay for electronic gear, and that their electronics experience is rather limited, cheap and easy seemed the way to go.

 

Yeah, this was a case I figured a picture was worth a thousand words. One of the reasons I like zener versions is quite literally they can not oscillate, and the 78XX series can have that issue occasionally. For all their inefficiencies zeners work pretty well too, and with fewer parts. This has some elements of tubes vs. transistors debate I suppose.

For what it's worth I've build what was shown, using green epoxy putty Radio Shack used to sell to encapsulate the results. I'd like to find something like that epoxy again, it was pretty useful.

What is more modern than a 78XX (and the 79XX)? Seems like it would be hard to improve on them. Even the LM317 and LM337 are just variations on the theme.

 

Well, I have a number of the 78xx and 79xx series on hand, and they're convenient if you need just that voltage, or like you've demonstrated, Zeners or other diodes can be added in the ground terminal path for other voltages (I did that recently with an LM78L05 plus a 6.9v Zener to get a 12v output).

The LM317/LM337's have a 50% higher output capability (1.5a vs 1.0a) and the fact that you can dial in the precise voltage you need with just a couple of resistors and/or a pot is a big plus; a few of them can take the place of a drawer full of 78xx/79xx regulators.

The LM78xx/LM79xx series have a fixed dropout of 2v; the LM317/LM337 have about a 1.8v dropout. Surprisingly, that gets worse when you use them as current regulators.

Newer LDO (Low DropOut) regulators might have as little as 0.4v drop across them. This means you have much less power dissipation in the regulator itself, which is certainly more "green" than the older versions. The newer devices are more expensive, because they haven't paid off their R&D and tooling costs yet, and are still developing newer and more efficient devices.

Linear Technology, National Semiconductor, Texas Instruments, Fairchild, ST Microelectronics and many other manufacturers seem to be coming out with new LDO regulators all the time. Then there's the switchers, buck/boost converters, ad nauseum. You can really get lost in the myriad selections that are available.

But our OP needed something inexpensive, easy to assemble, likely available everywhere, and would last. He won't be able to adjust the Vout with the 7809 regulator, but he has no need to do so - as long as it's 8.5v to 9.5v, he'll be in business. Just some filter caps, +12v in, and a means of connecting the supply to his phantom power supply.

Zeners are really convenient for low power reference-type supplies, but in this case his phantom supply is gobbling 200mA @9v, and with all those LEDs and the varying demands depending upon sound level to the mics - that would be a bit much for a Zener to regulate, methinks.

As far as the green epoxy encapsulating stuff - I'd found some pool patching epoxy compound at a swimming pool supply store a number of years ago. It was pretty neat; you just sliced off what you needed, then kneaded the putty-like substance until it was all the same color, and applied it to whatever you wanted to epoxy. Bingo- done.

Something else you might consider is red silicone RTV. I bought a pressurized tube of the stuff a few years ago; it was intended for automotive gaskets, but would work pretty well for potting small projects.

When I was on active duty, we had "potting compound" - you mixed up the two parts that made a yellowish and quite liquid mix, then poured it over your circuit that you'd placed in a form. We used it to insulate Sparrow missile simulators that we'd built on the 32-pin shear wafers that plugged into the missile umbilical on our Phantoms. I still have a couple of those simulators kicking around here, sans the potting compound. I'd made more than we needed.

These folks manufacture quite a variety of potting compounds; a number of them are NASA approved.
http://www.masterbond.com/