I had to order my JHS Andy Timmons Drive pedal from the United States (it is not available in my country).

Apparently the pedal does not use battery and requires a 9V DC power supply. I am not sure if I will need to order a JHS power supply for the pedal.

Can I use my BOSS power adapter to power the pedal? I would assume so as it the pedal has a 9V DC input like my BOSS pedals. I have not received the pedal yet, and can't really find much information around this.


EDIT: As per the accepted answer below, I used a BOSS PSA with this pedal without any issues, it is a standard 9v adapter like any of the BOSS pedals.

2 Answers 2


A Boss PSA-style PSU should work fine.

https://www.jhspedals.com/faqs/ says:

All of our pedals use a standard 9v DC adapter with a negative ground

Well, 9v DC, centre negative is the Boss-style PSU spec, the only one that in the pedal world that can be called 'standard'... but what about that 'with a negative ground' bit?

I stand to be corrected, but I don't believe that a typical pedal power supply, including the BOSS PSA, itself presents a 'true' ground to the pedal. 'ground' in a pedal context usually means what side of the power connector is connected to the pedal's case (and, consequently, the signal cables' shield).

Usually with pedals, this is the 'negative' side - i.e. the centre. I'll quote http://www.diago.co.uk/adaptors/positive-ground.html :

The Diago Positive Ground Adaptor allows positive-ground pedals to be powered alongside regular negative-ground pedals via the same power supply.

And I guess this is what JHS are saying about their pedals when they say 'with a negative ground' - just that they're normal in this respect. I guess it also means that if you are using a PSU with a true ground, it would have to be negative ground.

The only time I've had to worry about what is 'ground' was when powering pedals off a daisy chain - in this case, you need to know which side (+ or -) of the PSU input is grounded to the case as if you mix up 'positive ground' and 'negative ground' pedals, you'll short your PSU as both + and - will be connected to the case.


Boss power supplies are 9vdc, but the polarity is centre pin negative. There's a 50:50 chance. Doing a bit of homework reveals that JHS pedals use 9vdc negative ground. So, no, it's the wrong 50%. Unless you rewire the adaptor, or make a male/female dc lead that's wired back to front.Best buy the appropriate psu. The other factor of course is the power consumption of the pedal, and there's no clue that I've found - yet. Most of the JHS pedals seem to consume 100mA, and the Angry Charlie can be run on up to 18vdc, apparently, looking at the JHS site.

EDIT - checked with JHS and the site states that they run on 9vdc neg.centre. So it would appear that it'll be good to go.


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