Aion FX Maelstrom - Effect Signal Very Quiet at Max Blend

[nryerson]

Hey all, got a bit of a confusing one for everybody today.

I recently put together the Aion FX Maelstrom kit build for a good friend of mine, but I am running into a variety of interesting issues. First and most important - at max drive, volume, and blend the effect signal is super quiet. Now for the slightly odd part - by rolling the volume knob off it gets louder with the loudest signal being around 2-3 o'clock on the dial, basically like the max volume position is suddenly tapered off.

In addition, rolling blend off to add in the dry signal results in a much, much louder signal than when the pedal is set to the highest volume position around 2-3 o'clock. This is further accentuated when the effect is off, as the bypass signal is much louder than the overall pedal's effected signal, even with the blend knob rolled off. (I've attached a video showcasing all of this)

Schematic:



I'm honestly a bit stumped by now as all the pots work as intended, the pot values are correct according to the schematic, and voltages on all ICs and jfets look normal (pictures attached). Voltage in is correct, and bypass and effect positions both work and send signal. Visual inspection of the backside leads me to believe there are no shorts anywhere, but your eyes might be better than mine!

If anyone has any advice or wants to look at anything specific, do let me know!

Photos/Vid :





















Vid Link: https://youtube.com/shorts/3mrUvjxwDBs?feature=share

[ElectricDruid]

Welcome!

Thanks for making the effort to get all the information together so we know what we're looking at. And thanks for the video too, very helpful.

From watching your video, that doesn't sound right at all. I know you said that the pots all work as intended, but they really don't - most of them seemed to do very little. The bypass signal might be ok, but the effect signal is definitely not right yet.

You need an audio probe, and you need to go through the effect signal path to see how far the signal gets before it goes south. I can suggest some test points if you need help with the schematic.

Another way to potentially narrow down where the problem is would be to measure voltages on all the IC and transistor pins and then post them here - a simple list of which IC, the pin number and the voltage is fine. We *should* be able to tell from the voltages which bit doesn't look right. You've shown us some of the power voltages and those seem ok, so it's probably not that, but there's plenty of other pins on those chips!

HTH

[PRR]

> rolling the volume knob off it gets louder

Maybe it oscillates supersonic at "10", but not at "7". While oscillating it won't handle audio well. In that condition it may be sensitive to hand-waving near the boards and wires. (Yes, you may need three hands or a signal generator.)