tube synths

[Eric at Svetlana Electron Devices]

>Another obvious, and probably simple tube circuit that would no doubt be
>embraced is a full wave rectifier/frequency doubler, perhaps using
>12AX7(etc) as input stage and 6AL5 as rectifier.

Sure, an easy thing to do if you make a phase inverter
with the 12AX7, or use a push-pull transformer. Just like
running the same signal into both inputs of a balanced modulator.

>Eric, how much variation can your circuits take in the ht line? The
>transformer I have looks like spitting out +/- 170v when rectified.

Don't worry- --anything between 120 v and 250 v is okay.
This can even be extended in the VCO by using a lower-voltage
regulator tube. The other circuits can operate as low as 50v
without changes.

See, guys, tubes are very tolerant........
unlike some semiconductors I could name...........