Modified Devi Ever Hyperion

[mac]

This is a simplified Devi Ever Hyperion.
Two diodes instead of the PNP transistor, and one less resistor.

In a recent post PRR got me thinking about how the PNP transistor works.
I saw a Bazz Fuss with another diode going from B to Gnd.
No need for a negative feedback resistor, a silicon diode's tiny leakage can feed the base.
MPSA18 have more gain than those BC549C I used. That's why I increase Q2 collector, to match the leakage.
The bigger the resistor the tighter the sound.
In a Bazz Fuss a darlington does the job better since it needs very tiny currents in its base.

This is what I have on the breadboard right now,



enjoy!

mac

[matmosphere]

How does it sound compared to a Hyperion?

[mac]

I'll post a clip soon.

mac

[bobbysatya]

Built and verified! Used 2SC9014D with 630-ish hfe for both transistors. 10k resistor for Q2 gives it right amount of gate. With 100k it squeals. I have built the original hyperion but couldn't get it to work. This one saved me from frustation. Thanks Mac!

[mac]

 

mac