"Split" Pickups

pi_r_squared · #1 09-22-2008, 08:48 AM

I play bass for our church's praise team. During setup I find most of my time is spent tweaking the pickup volumes and tone on my bass to 'even out' the volume and tone for the different strings.

Specifically, my low E and A will sound the way I want them to, but my D and G will will be considerably quieter.
When I get the volume up on the D and G, the tone is considerably less "mellow".

My bass is a Dean EVO XM Short Scale, 2 soapbar style pickups, each with its own volume control.

My question is:

Is this a common issue? and when a bass uses a 'split pickup' (sorrry if that's the wrong term) are the two halves adjusted separately to help with this?

Also, I think I need to take apart a soapbar and look at the guts. How does the internal design differ from other designs? or is it just cosmetic? I saw a single (not split) soapbar pickup for sale on ebay that said it was for either 4 or 5 string. Is that even possible?

-Dan

SGD Lutherie · #2 09-22-2008, 08:55 AM

Generally the larger diameter strings are louder. So you want to adjust that side of the soapbar to be lower, while keeping the side under the higher strings closer to the strings. That's how you balance that out.

If you were using a split pickup with discrete coils, like a Fender P, you would also adjust the coil below the A and E strings lower.

There's not much you can do by taking the pickup apart, if you even can.

Just adjust the hight of the pickup to be lower under the low strings, which will bring their level down to match the high strings. The pickup should be fairly close to the strings on the treble side.

And how do you know those are split pickups?

Some soapbars are like guitar humbuckers, with two full length coils and they can work with any number of strings as long as the pickup is wide enough.The others are split like a P bass. They have to me made to work with odd numbers of strings, like a 5 string.

mjolnir · #3 09-22-2008, 09:01 AM

Yes, it's a common issue, and there is absolutely nothing wrong with adjusting one pickup or even just one side of a single pickup (or any combination you can think of really) to get your bass to sound the way you want.

As for the internal workings of a soapbar pup, it depends on the brand. The term "soapbar" is really just describing the general shape of the pup, not its internal workings.

pi_r_squared · #4 09-23-2008, 08:11 AM

Quote:

Originally Posted by SGD Lutherie

And how do you know those are split pickups?

Sorry if I was trying to stuff too much information into a question that it got muddy.

I wasn't referring to the soap bars on my bass, I was talking about some basses I have seen that have 2 overlapping pickups at one location. Maybe 'split pickup' is the wrong term.

pi_r_squared · #5 09-23-2008, 08:18 AM

The soapbars on my bass just have 4 screws.

I assume these are mounting screws, is it likely they offer some sort of adjustment?

If not, it seems like the only 'out' is to try shimming one side. If it's going to require shimming, is .030" a good place to start? or .060?

If i do need to shim them to adjust them, is there a preferred material? I know there are components where shimming can get ugly depending on the material used, but for a pickup it seems like almost anything would work.

Thanks again,

-Dan

mjolnir · #6 09-23-2008, 09:02 AM

Quote:

Originally Posted by pi_r_squared

The soapbars on my bass just have 4 screws.

I assume these are mounting screws, is it likely they offer some sort of adjustment?

If not, it seems like the only 'out' is to try shimming one side. If it's going to require shimming, is .030" a good place to start? or .060?

If i do need to shim them to adjust them, is there a preferred material? I know there are components where shimming can get ugly depending on the material used, but for a pickup it seems like almost anything would work.

Thanks again,

-Dan

The screws are there for adjustment. The general idea is to adjust each pair of screws (either on the treble or bass side) until the desired output is reached. If the pickup starts to wiggle after unscrewing one side a little, you should get some of that foam padding to stick under the pickup to tighten it against the screw heads. You can find some at allparts or any other bass parts website, or if you just have a spare mouse pad lying around you can cut a bit of that off and use it too. I hear other TBers 'round here have done that and it worked just fine.

pi_r_squared · #7 09-23-2008, 01:18 PM

Thanks all,

I measured the corner heights then took one pickup out over lunch today. It had that white sticky foam stuff about 1/4" thick, about 1/2" inboard from each end of the pickup. Adjusted just like you described.

I'll hook it up to my real amp tonight before I get too carried away with tweaking it.

Thanks Again,

-Dan