> 10 boards in your hand with a stencil 9 real days later for less than $50 shipped
Or I take my perfboard or solid copper base material and be done with it in one afternoon, without waiting 10 days and spending less than $50 shipped.
> For audio stuff you get the advantage of keeping everything nice and tight with lower noise.
IME it is way easier to do low noise / high bandwidth circuits on base material compared to making it work on a PCB layout. This is because the base material gives you a huge, continuous ground plane, and because you use all three dimensions, instead of just two (+- two component layers). Of course, semi-modern components require steady hands.
I hate to admit I only got into this after the EDA software and PCB fab services and Youtube soldering demos really hit the scene. I am a long time software engineer and it took the current ease of things to surpass my laziness barrier. I wouldn't be doing this at all if I was etching myself. Typical PCB prices are $5 per 10 two layer boards and an extra $15 per stencil. Most the price is shipping so if you order multiple projects at the same time the cost really goes down.
You make a good point about noise. If you are going to have a mixed board you better maintain separate digital and analog ground planes and perhaps even test a couple different layouts.
His pure analog schematics would be well suited to a 2 layer with one side being a ground plane and if any traces did have to be routed on the ground plane side it would be easy enough to ensure they were out of the way of any return paths.
Oh with base material I don't necessarily mean etching yourself. I rarely do that, I mostly use it as-is constructing my circuitry floating above it, suspended by its ground connections. It's somewhat similar to the Manhattan Style. It's also very easy to built custom shielding enclosures this way (all you need is a somewhat powerful soldering iron).
Or I take my perfboard or solid copper base material and be done with it in one afternoon, without waiting 10 days and spending less than $50 shipped.
> For audio stuff you get the advantage of keeping everything nice and tight with lower noise.
IME it is way easier to do low noise / high bandwidth circuits on base material compared to making it work on a PCB layout. This is because the base material gives you a huge, continuous ground plane, and because you use all three dimensions, instead of just two (+- two component layers). Of course, semi-modern components require steady hands.