Mod Line 6 DL4 to take standard center negative DC power supply

[cnspedalbuilder]

Hello, I recently fixed up a dead Line 6 DL4 and in the process I discovered it takes a 9VAC power supply. Supposedly it can also be powered with a 9VDC power supply using a center positive plug.

power schematic is here:
http://www.aronnelson.com/gallery/main.php/v/MrHuge/Line+6/DL4_ps.jpg.html

Now I'm feeling a little bold, and I'm thinking of a mod to work this with a standard 9V center negative power supply. I don't need/want to use the battery input, and it looks like the pedal expects 6V DC from the battery inputs. Could I wire the battery cables to a standard DC in jack and then power it with a center negative 9V DC cable? Would I need to add something to bring it down to 6V or would 9V be fine?

Sorry if these are simplistic questions, I'm finding the power supply section of the schematic to be pretty confusing. Thanks!

[Kevin Mitchell]

I've found that when my DL4 is powered by 9VDC (via isolated power supply) it doesn't like to stay on. It's simply not enough juice. My power supply has a switch to supply "14.5V / 12V (unregulated)" instead of 9VDC which is to accommodate these Line 6 modeler pedals.

-KM

[cnspedalbuilder]

Thanks Kevin, from what I've seen it can be powered from 9VDC if it has enough current (like a one spot), but even a 12V would be ok if I could use a standard center negative plug. It's not horrible to use center positive but it just bugs me   

If I could run standard center negative 9 (or 12)V via the battery wiring, that'd be awesome.

[Kevin Mitchell]

I believe you're right.

I'd imagine the easiest thing to do without modifying much would be to tack on a power jack with reverse wiring. That way you could use a standard wallwart.

Or alternatively you could just grab the Line6 6VAC wallwart 

-KM

[cnspedalbuilder]

FWI, I did it. Connected a standard DC jack to the battery cables, wired center negative. So there is an option to use a center positive DC in or center negative on the side. Even though it is supposed to get 6V from the battery, my 9V input seems to work ok. If anyone has a look at the schematic and thinks I may be frying one of the power protection diodes (or worse), pls. let me know. For now anyway it works well.

Whatever the case, I definitely recommend modding this pedal to replace the switches and power jack. I am guessing the pots will go soon too considering how much they wobble, but until then, I've got a working pedal! I will probably have to trade my gristleizer for this, but that's ok, it will give me a chance to build another