Author Topic: Yet another PCB-less Matsumin Valvevaster question  (Read 1327 times)

Marcos - Munky

Re: Yet another PCB-less Matsumin Valvevaster question
« Reply #20 on: June 03, 2020, 04:42:40 PM »
It could be the power supply. Try to use another one (check the plug pinout).

MontyS12

Re: Yet another PCB-less Matsumin Valvevaster question
« Reply #21 on: June 05, 2020, 11:11:02 PM »
What I'm plugging it into is just a standard 9v tap from my pedal board.

MontyS12

Re: Yet another PCB-less Matsumin Valvevaster question
« Reply #22 on: June 08, 2020, 04:26:46 PM »
Ok. Swapped the DC power jack and i got the same behavior. With pedal plugged in and no tube, I get 9.04v. With tube inserted and plugged in to power, I get a reading of 8.61v

Marcos - Munky

Re: Yet another PCB-less Matsumin Valvevaster question
« Reply #23 on: June 08, 2020, 04:40:01 PM »
How much current is the tap of your pedalboard capable to output? Tube circuits requires way more current than opamp circuits, so maybe your power supply can't handle the current.

MontyS12

Re: Yet another PCB-less Matsumin Valvevaster question
« Reply #24 on: June 08, 2020, 06:21:16 PM »
Ah, good question. Apparently only 100ma or 200ma depending on which taps are used....

MontyS12

Re: Yet another PCB-less Matsumin Valvevaster question
« Reply #25 on: June 08, 2020, 07:24:10 PM »
yeah, I've had it on a 600ma adapter separate from my pedalboard and it has not repeated the behavior. Hope that was it. Had complete forgotten that milliamperage on my dc brick was so low...
« Last Edit: June 10, 2020, 01:47:19 PM by MontyS12 »

Marcos - Munky

Re: Yet another PCB-less Matsumin Valvevaster question
« Reply #26 on: June 08, 2020, 07:35:49 PM »
So that's probably the cause of the issue. It's not your dc brick that have low amperage, it's the tube that draws too much current. A tube screamer draws about 7.5mA, so you can power 13 tube screamers with the 100mA tap. On the other hand, a tube draws 150mA just for the heaters when you power them with 12V.