The Tower - Rev B

So I managed to fix the issue I alluded to in my previous post - that issue being an excessive amount of extremely high--frequency noise (nails on chalkboard type) introduced with the controls at certain points. I managed to eliminate the noise by adding a 4.7nF capacitor from pin 7 of the 6LE8 to ground. I also made some miscellaneous changes, the biggest of which is the addition of a four-position rotary switch that will change the frequency at which regeneration occurs. 

While I was trying to diagnose the noise issue, I used my capacitor substitution box and I was trying to see how changing the value of C15 in the original schematic affected things. I really liked being able to change the range of the feedback oscillations, so I decided to add the switch. It is entirely optional; you can just pick a cap value and use that, as per the original design.

Here is the updated diagram - as always, click on the image to make it larger, then right-click on the engorged image and click 'Open image in new tab' to see the full size.

Still working on audio/video demos, and trying to figure out how the hell to get this page to work the way I want it to.

XVI: The Tower Vacuum-Tube Preamp and Demodulator

REVISION NOTE: 

This design has been revised. An updated schematic is available. These principles of operation still apply, however the revised design eliminates excessive high-frequency noise (the kind that sounds like nails on a chalkboard)

Click on the image to embiggen, and then right-click and select 'open image in new tab' for full size.

XVI: The Tower is a trio of pissed-off pentodes that hate you and whatever you put through it. It will send your audio signal into the pits of an alien hellscape, and then give whatever is left of it back to you. If you plug CV into it, it will turn into a ring modulator. If you don't have CV plugged into it, it will modulate itself.

I am pretty proud of this monstrosity, I won't lie. It's insane. It's got it all. 

Are you a boring, middle-aged white dude who just wants some 'WARM TOOB SATURATION ON MY MIX BUS, BRO, JUST TO TAKE THAT digital edge OFF?" This can do that, sure.

Are you a boring middle-aged white dude who USED to be hardcore back in the late 80's and early 90's, but you never let go of your inner rivethead? 

Holy shit do I have just the thing. This is going to set a fire to your loins, let me tell you. 

Do you like birds? Oddly enough, this is for you, too, I guess? Because it can make some killer bird sounds.

Look, this isn't for everyone. This is weird shit that uses weird tubes in weird ways. This isn't some regurgitated HM-2 "inspired" clone, or some Buchla or Moog "inspired" thing. The only comparison that I can give you is Metasonix. If you like Metasonix, you will love this. If you hate Metasonix, you will hate this.

I am not a sales-person, nor am I a business-person (if I was I wouldn't be just vomiting this shit all over the Internet, I would be trying to sell this god damn thing) so that's my pitch. It's a DIY project, anyway. Either that sounds like your jam or it doesn't.