On 04/24/2018 10:37 PM, James Knott via talk wrote:
At one point there were spring based audio delay devices use for adding reverb but they quickly got replaced with memory based solutions when dram started showing up. They weren't spring based, just a loose coil of wire.
Take a look at https://en.wikipedia.org/wiki/Reverberation under Spring reverberators. These are the ones I knew of but there may have been some other devices based on other operating principles. I remember those reverb springs, from back when I was a kid. The delay
On 04/24/2018 10:33 PM, Alvin Starr via talk wrote: lines I'm referring to look like the one pictured in this link. https://en.wikipedia.org/wiki/Delay_line_memory#Magnetostrictive_delay_lines
Forgot to mention, that brass rod at the front is threaded and used to position the pick up transducer, which is that blue block. You'd range the delay line by jamming a key to provided constant characters and then adjust the screw one way and then the other, to the point the text on the display started breaking up and then set it half way between the 2 points.