Power sag for guitar EFX


Update 07/07/2024 I started making the dying battery effect in 2011 (by request for Christian Hand). Since then I have updated the design a couple times but the last version is was a complete overhaul of the circuit. Since then a lot of different companies have started offering some version of this effect. I have … Read more

Stereo phono preamp using JAN 6418 tubes

Here is a nice little stereo phono preamp using a pair of JAN 6418 subminiature tubes. This design uses very few components and adds a nice bit of extra oomph and tube tone sparkle to your input signal. I have tested on turntables and cassette decks with great results. Using an IC7660s as a charge … Read more

Sub Mini Tube Booster with the JAN 6418

Here is a stripboard layout I did for a preamp/boost using the JAN 6418 subminiature tubes I have been experimenting with lately. It is based on the schematic from the previous post, but rather than powering the heater with a 1.25-volt battery, I utilized an LM317 voltage regulator and a 100-ohm resistor. This ultra-simple circuit … Read more

Low Power Vacuum Tube PreAmp

I have wanted to learn more about vacuum tubes for years but was always put off by the extremely deadly power requirements. Working with low power sources for so long, I have blown my fair share of capacitors, which is scary enough for me. Recently I discovered the world of sub-miniature vacuum tubes and the … Read more

POTAR Design Devices