6-string pickups in a 5-string Jazz Deluxe???

[Dr. Riddim]

Hi all,

I've been offered an American 5-string Jazz Deluxe at a pretty reasonable price, but it's been modded with a pair of EMG 45's (a DC in the bridge position and a P in the neck) and the BTS active tone circuits.

The pickups look a little out of place because they're so wide, but I can live with that. What I'm not so sure about is string response.

I took it on a gig last night and I found that when I started to dig in the sound squashed as if there was a compressor in the signal chain (there wasn't), especially on the higher strings. The strings themselves are light gauge (40-125) Ernie Ball Supers and the action's set low.

My first thought, of course, was the battery so I put a fresh one in and it did the same thing. Then I started thinking pickup height and/or string gauge.

The other thing that occurred to me (too late to try it on the gig, though) was that it might be a phase cancellation problem being caused by the placement of the pickups. I had the blend knob centered and haven't had a chance to try it in another position yet.

My main question is should I even bother with this bass? Is the basic premise (6-string pickups on a 5-string bass) flawed to the extent it's going to compromise the playability? Is the "compression" problem most likely being caused by the pickup to string relationship or something else?

Anything you guys can tell me will be appreciated. Thanks.

Bill

[Searcy]

I would guess that the 6 string pickup in the 5 string bass isn't much of a problem. I would think the battery is funky like you did. After that I might try adjusting the pickup hight some to see if that helps the sound. EMGs like to be close to the strings. But I wouldn't think it's a compatibility problem. Those sorts of problems usually show up as uneven string response. One sting louder or quester than the others. You don't seem to have that problem.

[Dr. Riddim]

Thanks for the reply Searcy. At lower volumes with a light touch I don't notice any glaring difference in output from string to string.

I've used EMG's in the past and my experience is that they don't have as strong a magnetic field as Alnico or ceramic pickups. Because of that I do tend to run them closer to the strings and I've never had a problem with magnetic interference.

I'm going to change the strings to a slightly heavier set just to see if the added mass will alleviate the problem. Thanks again for your help.

[Searcy]

Most EMGs are ceramic magnet pickups. The lower output is due to the smaller coils.

I good set of new string usually goes a long way to help evaluate a bass. Smart thinking.

[Dr. Riddim]

I don't know what kind of magnet I thought EMG's had in them, but due to the fact that everyone says they aren't as "magnetic" as other pickups I figured they weren't either Alnico or ceramic. Thanks for correcting me.

I stuck a set of .045 - .105 Alembic steel roundwounds on it (I retained the .125 Ernie Ball "B" string) and the difference was noticeable. I still feel like it's squishing, but it's nowhere near as bad as it was with the Ernie Balls.

I'm going to keep experimenting with pickup height and string sizes and see if I can't get the squishing to go away completely.

Thanks for your help.

Bill

[Dr. Riddim]

UPDATE: After some research on the EMG website and a phone call to their tech support folks, the problems have been identified and are being solved.

The pickups were being run on 9V, but EMG says they need to be run at 18V. I re-routed the original battery compartment to make it all the same depth and was able to easily put 2 9V batteries in there without any visible modification.

The other problem was that the upper pickup was a 6-string P-type and the positioning of the coils was such that there was a gap in coverage on the A string. I'm ordering another pickup from EMG to replace that one - a J-type AND a dual-coil in the same housing. Should sound killer...

Thought you might like to know.

Doc

[Philbiker]

Nice follow-up!