Harley Benton JJ-55OP wiring diagram

timmus

timmus

Just a Stranger Passing Through
Supporting Member
Apr 2, 2009
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South Central Missouri
#1
All,

Before I tear into this bass I'd like a bit of guidance, It's a new to me bass...I'd been looking for one of these for quite some time and finally found the one I wanted, the blue one. The gent I bought it from had replaced the p'ups with Seymour Duncan p'ups,...emailed him to see if he remembers what pick ups he used but they look like quarter pounders. Also trying to figure out if he used a SD preamp or used the original one. I haven't heard back from him yet but I only emailed him about 15 minutes ago.

Well, you may ask, what's wrong with it??? The controls are volume, p'up blend and concentric EQ knobs and when I turn the blend to the bridge p'up it has no output so I'm guessing there is a wiring error in there somewhere. It may become painfully obvious once I open it up and do some signal tracing but I'd rather have a schematic on hand if possible before I dive into this.

Ultimately, I'd like to find a HB schematic for this bass but I doubt they are easy to find. I know that these basses are somewhat of a copy of the Aria Pro Detroit model but I believe the Arias are passive only,

I will probably bulldoze off my setup bench today and put this on it and see if there is anything obvious.

Thanks!
 
#2
Sounds like a pretty common wiring scheme. I'm sure if you post a pic of the current control cavity, someone can point you in the right direction.
 
#4
OK, I popped the back cover off and didn't see anything obvious. What I did end up finding is when the previous owner soldered the pick up wires to the blend pot PCB, one of the pads had separated from the trace. It was impossible to see, even with a 10x eye loupe but an ohm meter doesn't lie. I put one probe on the pad and the other probe on the leg of the affected pot and nada. I ran a small gauge wire from pot leg to the pad and we had sound on the bridge pick up! I cleaned up some of the wiring and put it all back together. It needs a setup for the way I like it but over all, even without the setup, it sounds pretty darned good.
 
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#6
mcnach said:
If you ever need to check the original wiring, let me know. I have one and I can easily take a few pictures. :thumbsup:
Click to expand...
Thanks but I got it sussed out. HB actually sent me a schematic and it says on it that it's for the 55OP but it doesn't seem to match what I was seeing in under the hood. Attached is what they sent me.

EDIT: well huh...I tried to attach the PDF but it is giving me fits. I'll try to attach file later after I figure out the problem.

Figured it out... :thumbsup:

FWIW:

1729019448722.jpeg
 
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