Author Topic: Digitally controlled analog effects  (Read 2343 times)


Re: Digitally controlled analog effects
« Reply #40 on: May 18, 2019, 12:41:15 AM »
You can also cut trees, dry the wood, kiln it down to charcoal, boil animal skins down to hide glue, then grind the charcoal to powder and mix up every-so-carefully your own carbon composition mixture, roll up and glue paper straws for body cylinders, then cut out tiny circles of metal and braze or weld lead wires to these to-be end caps (unless you have an interest in finding and smelting metals to mix your own end cap and lead alloys) then made a few zillion trial attempts and measure out your own precision resistors.... hmmm, really ought to construct a moving-coil meter from first principles, then make your own meter from your refined conductor wires.

Did you know that it's entirely feasible to draw your own wire? I've actually done this. Once. Got blisters and broke the wire getting it finer, but my drawing plate worked OK. Rendered hog lard makes a great machining lubricant, btw.

I suppose one could find and refine one's own tin and lead to make solder. Flux is refined pin resin.

By now you're thinking that you didn't want to go that far in the quest to DIY everything. And that is the point. Each person needs to decide what level of stepping back away from manufactured goods is sufficient to scratch their DIY itch. For me, I have a mania to learn the technologies and processes, but at some point, I'll take a moderately manufactured part to craft into my own end result. You may want to go refine your own potassium nitrate, hydrochloric acids, metals, other reagents and work from first principles.

I'm personally good with (ab)using ICs now. When I graduated college in 1973, I was disappointed that circuits would be cased up in every more integrated epoxy packages. I wanted to design the innards right down to transistors. Maybe I've mellowed over the years. Or gotten lazy.

Quick IQ Test: If anyone in a governmental position suspected that YOU had top-secret information on YOUR computer, how many minutes would you remain outside a jail cell?


Re: Digitally controlled analog effects
« Reply #41 on: May 19, 2019, 01:13:05 PM »
> cut trees, dry the wood, kiln it down to charcoal, ...grind the charcoal to powder and mix up... your own carbon composition
> Flux is refined pin resin.

Resistor stuff was powdered coal, not scorched tree-stuff (which was usually burned green). Comes right out of the processes that the Thoreau ("Walden") family developed to make pencils after that one deposit of good graphite in England was worked-out.

Pin resin? How hard do you have to squeeze a pin to get resin? Now pine resin, that's easy. I can scrape you a pound on my land. Large parts of Maine and the Carolinas had pines harvested and boiled for "naval stores", not belly-button shops, but turpentine and rosin for sealing wooden ships. Apparently rosin extraction is now done not by steaming but with Zippo fluid.
« Last Edit: May 19, 2019, 01:15:40 PM by PRR »


Re: Digitally controlled analog effects
« Reply #42 on: May 19, 2019, 02:54:21 PM »
I did some work on this a few years ago. Digital pots are the way to go imho. Have a look at this in case you find anything useful:
The original links don't work any more but I posted some more links later in the thread that should be OK. Have fun! :)


Re: Digitally controlled analog effects
« Reply #43 on: May 19, 2019, 05:43:27 PM »
Ah yes, I remember it!

Your Design Notes on that pedal are especially good - a nice discussion of some of the problems faced and why you chose the solutions you did. Very topical.

Thanks for sharing it.


Re: Digitally controlled analog effects
« Reply #44 on: June 02, 2019, 06:20:31 AM »
Cheers Tom, I used the same approach for a programmable distortion based on a Suhr riot with a Sansamp tone stack grafted on, it performed very well so I will post the design when I get time to write it up.