Blue Jinn
Rider of the ARPocalypse
Hi,
Came across this 6n2p pre with a built in limiter. I don't want to try building this one at the moment. But looks like the gain is in the feedback like in the one bottle, so wondering about using the limiter and putting it in the NYD 1 bottle, tapping from just before C4 with the vactrol strapped across R12 and R11? (or just across the pot?)
I don't know much about vactrols really, and frankly don't understand how the Norton opamp circuitry actually works, as I'd expect that the higher the signal sent to the compressor stage, should reduce current so that the LED gets darker increasing the photoresistor value to reduce gain in the feedback loop, or maybe I've got that backwards. I'm assuming that is what is occurring?
Don't know if this can be used unmodified, (the gain pot is 10x the value in the NYD) or if a different vactrol should be used, but the concept seems intriguing.
(per the website, the copyright allows for re-distribution for personal or non-profit use only.)
Here's the NYD one Bottle:
One-Bottle Preamp
Here's the 6n2p w/ compressor: (sorry about the resolution, the pdf file exceeded the 64k limit.....)
View attachment 63986View attachment 63987
Came across this 6n2p pre with a built in limiter. I don't want to try building this one at the moment. But looks like the gain is in the feedback like in the one bottle, so wondering about using the limiter and putting it in the NYD 1 bottle, tapping from just before C4 with the vactrol strapped across R12 and R11? (or just across the pot?)
I don't know much about vactrols really, and frankly don't understand how the Norton opamp circuitry actually works, as I'd expect that the higher the signal sent to the compressor stage, should reduce current so that the LED gets darker increasing the photoresistor value to reduce gain in the feedback loop, or maybe I've got that backwards. I'm assuming that is what is occurring?
Don't know if this can be used unmodified, (the gain pot is 10x the value in the NYD) or if a different vactrol should be used, but the concept seems intriguing.
(per the website, the copyright allows for re-distribution for personal or non-profit use only.)
Here's the NYD one Bottle:
One-Bottle Preamp
Here's the 6n2p w/ compressor: (sorry about the resolution, the pdf file exceeded the 64k limit.....)
View attachment 63986View attachment 63987
