Failing mode switches in digital BOSS pedals

[Pepe]

A member of the I Love Fuzz forum was worried that the BOSS PS-2 that is on the way to him could have a faulty mode switch of this kind as well. I assured him that the PS-2 has a real mechanical switch for the six modes, not this resistor value dependent switching system.

The first compact BOSS pedals that featured this resistor scanning switching method with potentiometers were the HR-2, PS-3 and RV-3, all introduced in 1994.

[laurie]

Sooo... I have just picked up a DD-6 with a missing mode "switch". Pepe - confirming, you simply used a standard 50k linear potentiometer, with no detents, to fix yours?

[Pepe]

Absolutely correct. A 6mm 50k linear potentiometer with knurled shaft. Then you can also reuse the blue knob.

[laurie]

Just installed a 50k linear pot and it works perfectly. Too much clockwise travel but it just sits on the longest delay time for the excess travel.

[Pepe]

Yep, too much travel, but it works and there is no further flaw. And I think it should be failure proof even if you accidentally stomp against it, because it has no detents.

I bet that we are going to see dozens of those failing switches in the future. This switching method relies on highly accurate resistor values at the detent positions. You have to treat them carefully to ensure the perfect working mode. But those are pedals, intended for being stomped by feet. And they are made for guitarists, who aren't generally known for their wariness or soberness. A very unfortunate conjunction, if you ask me ...

[Dirk]

I had a PS-6 years ago with a similar problem, the different modes would be all glitchy, some were missing, some were the same no matter where you put the switch, very strange. It got fixed under warranty, but developed the same issue like a year later. I ended up selling it as is.

[Pepe]

Ah, yes, I remember that one. Now that we're a bit wiser we can simply swap such a switch potentiometer for a standard potentiometer and everything is back to normal.

[fuzzbuzzfuzz]

I feel also that if the mechanical detent over times becomes less pronounced (with the constant back and forth rotation by user) the pot simply does not hang on the spot (With that small window of contact tolerance) to work, EHX pedals are definitely the worst offenders, but I am very cautious of BOSS too. My PH-3 had this problem.