I love it! I made a couple of these with my kids years ago. 386 battery amps are fun. I still have an old Smokey Amp and the Danelectro Bacon N' Eggs that get regular use.
This is super rad! You should sell them as like a Pete Cornish edition Tuner for a couple hundred bucks. This is infinitely cooler than any DIY tuner I’ve seen. I just use the Boss Tuner app so this has inspired me to rehouse my iPhone into a 125b!!
I used to use them. Many many years ago they were kind of the diy/boutique standard. But the days of battery clips and building outside of the box are long gone.
Why? Do you measure and sort other components with broad tolerances, like pots? How would you even implement this knowledge? No commercial builder cares, why should you?
You'll be fine. This circuit is pretty slutty, it'll get along with just about anything. The advantage of rolling your own is that you can adjust the distance and angle of the LED/LDR combo to balance the response, unlike a vactrol which is fixed.