Jazz Bass Wiring problem. (HELP!)

[richardzbaraski]

I've just purchased a 1975 jazz bass!

Only problem is that when I have the all controls open the neck pickup bypass's the bridge pickup and then when I roll it off the bridge pickup is really loud! Is there any way to solve this?


Rich

 

[iiipopes]

Welcome to the world of J-basses. When all controls are dimed out, there will be a slight volume drop due to the impedance drop and comb filtering of having both pickups full on. I solve this by adding a .01 cap inline between the hot lead of the bridge pickup and the center lug of the bridge pickup volume control. If you want more growl, I substitute a .033 tone cap for the stock .047 tone cap to retain more mids in the mix.

Until I did this, on my '75 sunburst/rosewood light ash J-bass I had in the early '80's, (Don't worry - I know who owns it and I get to borrow it any time I need that tone) I usually played with the neck pickup full on and the bridge pickup rolled off to about 8.

 

[elBandito]

I have a bag of .01 caps kicking around. Going to try this out.

Welcome to the world of J-basses. When all controls are dimed out, there will be a slight volume drop due to the impedance drop and comb filtering of having both pickups full on. I solve this by adding a .01 cap inline between the hot lead of the bridge pickup and the center lug of the bridge pickup volume control. If you want more growl, I substitute a .033 tone cap for the stock .047 tone cap to retain more mids in the mix.

Until I did this, on my '75 sunburst/rosewood light ash J-bass I had in the early '80's, (Don't worry - I know who owns it and I get to borrow it any time I need that tone) I usually played with the neck pickup full on and the bridge pickup rolled off to about 8.

 

[fhm555]

...I usually played with the neck pickup full on and the bridge pickup rolled off to about 8...

While I rarely play at full volume, I almost always use more neck than bridge volume.

 

[walterw]

Only problem is that when I have the all controls open the neck pickup bypass's the bridge pickup and then when I roll it off the bridge pickup is really loud!

i have no idea what you mean here; "the neck pickup bypasses the bridge pickup"?

 

[Fernando Costa]

Welcome to the world of J-basses. When all controls are dimed out, there will be a slight volume drop due to the impedance drop and comb filtering of having both pickups full on. I solve this by adding a .01 cap inline between the hot lead of the bridge pickup and the center lug of the bridge pickup volume control. If you want more growl, I substitute a .033 tone cap for the stock .047 tone cap to retain more mids in the mix.

Until I did this, on my '75 sunburst/rosewood light ash J-bass I had in the early '80's, (Don't worry - I know who owns it and I get to borrow it any time I need that tone) I usually played with the neck pickup full on and the bridge pickup rolled off to about 8.

Hi iiipopes, I really don't like this volume drop when two volumes are open. I never heard about a .01 (103) capacitor in series with the bridge pickup solution. This solves the issue without changing the sound quality? How this works? I think Fender should implement it at their JB. Sorry for so many questions, is that I intend to try it. Thanks in advance.

 

[iiipopes]

The .01 inline capacitor does cut some low end. But there is so little string excursion over a J-bass bridge pickup that there really isn't any fundamental to lose, anyway. The only down side is that on some basses, depending on what kind of J-bass bridge pickup and the particular setup, there may be a little bit of volume loss on the bridge pickup, like it was turned down to 9 or 8 1/2 permanently. But find a J bridge pickup that likes being really close to the strings with good output and it should not be an issue.

Fender actually did implement it - but as a .0068 capacitor on the bridge pickup of the Jaguar guitar. Rickenbacker have done it on the 4001/3 with a .0047 capacitor ever since they have sold two-pickup basses, and their 4002 model has the .01 instead of the .0047, because on the 4002, instead of the traditional pickup in the traditional place for a Rick, it has an end-to-end humbucker in a Rick neck pickup sized housing in the same place as a J bridge pickup. That's how I arrived at the particular value. Hope this helps.

 

[Fernando Costa]

Hi iiipope, sure this helps, if I understand, there may be some lows lost, irrelevant in the bridge pup, and the volume decrease, which depends on the kind of pup, can be compensated by raising the pup. It's a simple modification to be done and undone if I do not sounds good. Thanks also for the information on other instruments that use this solution. Much information that I did not know. Thanks.