The schematic for the Valhalla keeps referencing a +9V rail, yet the voltage regulator is LM2940CT-12, which is a +12V regulator.
The Diezel VH4 appears to have 12-18V marked on the case above the power jack. I suspect there was an issue transcribing the schematic.
If you're experiencing issues, you may want to try using a 12v power supply with the pedal. My good friend and I were playing with his board and it DID function at 9v, although i would speculate that this makes the regulator unhappy [hot].
The Diezel VH4 appears to have 12-18V marked on the case above the power jack. I suspect there was an issue transcribing the schematic.
If you're experiencing issues, you may want to try using a 12v power supply with the pedal. My good friend and I were playing with his board and it DID function at 9v, although i would speculate that this makes the regulator unhappy [hot].