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Advanced Member
Username: tmoney61092

Post Number: 356
Registered: 9-2008
Posted on Thursday, April 29, 2010 - 6:00 pm:   Edit Post

so just wondering if anyone can explain the difference in 2 jazz, 2 precisions, and a precision and a jazz pickup up combination and the sound that each can give and the difference in them.

~Taylor Watterson
Senior Member
Username: crobbins

Post Number: 594
Registered: 6-2004
Posted on Thursday, April 29, 2010 - 6:26 pm:   Edit Post

Senior Member
Username: ajdover

Post Number: 819
Registered: 11-2003
Posted on Thursday, April 29, 2010 - 6:46 pm:   Edit Post

I don't personally notice that much of a difference between different P/J combinations. What I notice more than that is where they are placed, whether they are active/passive, and whether they are humbucking/cancelling or single coil. I have basses with MM pickups, J Bass pickups, and P-bass pickups. Some are active, some aren't, some are JJ, some are MM-J, and some are not (my Alembics, Gibsons, etc.). To me, the biggest difference isn't the type of pickup, but what I've noted above.

The one exception I'd note is my Lakland 4-94. The MM style Bartolini pickup near the bridge (it also has Bartolini active electronics) features the ability to split coils on the pickup, e.g., front coil, both coils, rear coil. Because the coils are located in different positions on the pickup itself, it means they're also located at different positions along the string length. As such, they will replicate different tones due the vibration of the string at that point. It remains the only bass I have that can go from a P sound, to a MM sound, to a J sound, and to a Fender-both-pickup-sound at the flick of a switch. It's one of the reasons I love that bass to death, and will never sell it.

Senior Member
Username: bigredbass

Post Number: 1384
Registered: 9-2002
Posted on Thursday, April 29, 2010 - 11:53 pm:   Edit Post

Beginning with the original design Fender pickups, the Precision pickup is a humbucker, the two pieces joined in a humbucking fashion the same as the side by side coils in a Gibson humbucking pickup. The sound, relative to a Jazz pickup is 'fatter'.

The Jazz pickup is a single coil design, essentially a bass development from a Strat or tele pickup. It will typically sound 'thinner' than the Precision pickup.

Of course, these terms are very subjective but most people will tend to hear them this way.

Of course over the last 50 years there have been countless versions of these pickups, both from Fender themselves, and the aftermarket (everything from DiMarzio and Seymour Duncan, to Aero and Nordstrand and EMG and Bartolini and on and on), both in passive/high impedance (no battery) to active/low impedance (usually 9v battery, and can include active tone networks in the bass). Even ALEMBIC offers versions of these warhorses in their Activator pickup line.
And lots of these choices include a Jazz pickup that is a stacked humbucker, where the coils are stacked on top of each other instead of side by side, in an effort to eliminate hum.

Placement choices aside, two P's are very full sounding, maybe too much for a lot of guys, since we see so few basses built this way. But Leland Sklar and John Entwistle are/were big fans of this layout.

Two J's are very in vogue these days. In true single coil/passive layouts, this is the tone you hear on tons of recordings. Move on to two stacks or an active setup, and the tone is still there, but in a maybe more refined version.

For me, the P+J is the best of both worlds. In the late 70's, when Precision basses ruled the world, guys wanted a little more articulation to go with that fat one-pickup P-Bass thump. So you began to see guys adding a Jazz pickup to their P-Basses in the bridge position, and it became a really popular mod. Yamaha formalized this layout with the BB2000 bass in the early 80's in a production instrument, and this layout has been around from many builders ever since.

For me, the P+J is the 'just right' version for the Fender-style pickups. I would tend to prefer a stack J pickup in this, as I hate that single coil hum that's possible in many situations.

But . . . pickups, like most things musical, are very subjective, and tone is the result of a lot of choices. So you'll just have to try different axes and pick what's right for YOU.

Oh, and yeah, the Activators are my-tee-fine ! !

J o e y
Senior Member
Username: mike1762

Post Number: 522
Registered: 1-2008
Posted on Friday, April 30, 2010 - 3:49 am:   Edit Post

I always considered P Bass PUPs as single coil. I understand that they have opposing windings and polarities. But since one coil is serving the E and A strings and the other the D and G strings, wouldn't the single coil tone be preserved? I figured the "warmer" tone of a P Bass was a manifestation of PUP placement.
Senior Member
Username: serialnumber12

Post Number: 723
Registered: 12-2004
Posted on Friday, April 30, 2010 - 4:14 am:   Edit Post

What's going on with Series electronics is pretty unusual - there have only been a handful of other guitars that use this sort of noise reduction system (Fender Strat Elite and the original Paul Reed Smith Bass both from the 80s as far as I know).

A magnetic pickup is composed of a coil of wire sitting in a magnetic field. The pickup is positioned so the strings are in the magnetic field as well. When a string containing iron moves it disturbs the magnetic field of the pickup, which induces an electric signal in the coil. That tiny signal is the sound of your string vibrating which you can amplify.

The coil not only responds to magnetic disturbances from the strings, but will pick up electromagnetic interference (EMI) as well. This is where hum and buzz come from.

Single coil pickups are very sensitive to EMI. This led to the development of many kinds of dual-coil pickups to try to fix the problem. A clever guy figured out that with two matched pickups, you can get rid of the hum by connecting the second pickup backwards. The EMI created the same buzz in each pickup, but when you connect them out of phase, the buzz is cancelled.

That's great, but the sound from the strings is also out of phase, which means very little bass and a tinny sound. But an even more clever guy noticed that if you flipped the magnets in the pickup over AND wired the pickup backwards, then you could cancel the EM noise, but have the signal from the motion of the strings still in phase. Now that's really good! This is how a Jazz Bass works or the in-between sounds on a Strat are quiet. A Gibson-style humbucker puts two of these coils right next to each other for the same effect.

But things are not perfect. The reversed polarity /reverse wind coil combo kills noise, but since each of the coils hears the string in a slightly different position, there's some cancellation of sound as well. This cancellation is why humbuckers don't sound as bright as single coil pickups.

Well, people are pretty darn clever, and somebody else figured out that if you wired two coils out of phase and didn't put any magnet in one of the coils, it wouldn't hear the string vibration but would still get rid of the noise - a quiet single coil with traditional single coil sound. This is what a Series bass humcancelling dummy pickup is - it's the coil with no magnet and is performing the noise reduction for both the pickups.

Theoretically, are almost perfect now, but one problem you now have is that you have to wind a coil that's precisely matched to the working pickup, but it can't pick up the instrument's sound! This is expensive in the case of the Series bass because there are active electronics. So you're seeing a great example of "cost is no object" perfectionism in the Series basses, which have an extra route for a dedicated dummy coil which even includes it's own dedicated preamp - what other bass has an active circuit which is there only to remove noise! In the case of a Series bass, the two pickups and canceller are carefully wound as a matched set to maximize noise reduction, and the electronics are tweaked to minimize noise without impacting sound (this is the low-noise mod that Ron does personally on the Series basses).

As anybody with a Strat or Tele will tell you, EM noise is often directional - you turn your body and the amount of buzz will change. So, you really want the humcanceller to be in the same orientation as the pickups, hence the Series humcanceller position between the pickups. But because the canceller doesn't need to be near the strings, you can put it else where in the body and it should work. The old PRS basses had three regular pickups plus a dummy coil that was exposed on the back of the bass; the Fender Elite had a fourth coil under the pickguard.

The Series design is non-compromised and expensive. One other extremely clever variation is an old one - Leo Fender's split coil Precision pickup from the late 50's. He was really clever on this on - there are two pickup sections that each sense two strings. They are matched and have reverse polarity and winding relative to each other. So, the coil under the E and A strings does double duty - it "hears" those two strings, but it also acts as a hum-canceller for the D and G strings - it can't hear the string motion, but does cancel the noise! Very, very clever! This kind of design works pretty well on a bass, but having a split coil pickup on guitar doesn't quite sound the same (some of Leo's G&L guitars had this kind of pickup).

[moderator's edit: added attribution to source]

Thanks to David Fung in this thread for the above quote.

(Message edited by artswork99 on April 30, 2010)
Advanced Member
Username: tmoney61092

Post Number: 357
Registered: 9-2008
Posted on Friday, April 30, 2010 - 8:09 am:   Edit Post

well i was wondering because i was considering buying a Warwick Stryker and were wondering what kind of sound i could expect out of the mirrored P pickups compared to having one with 2 J or having 1 p and 1 j, so if anyone could maybe describe that if they have experience with it that'd be great

Senior Member
Username: sonicus

Post Number: 885
Registered: 5-2009
Posted on Friday, April 30, 2010 - 8:56 am:   Edit Post

I had a passive "Stars Guitars " Bass once that had a double "P Bass" pickup configuration. It was a bolt on neck variety. I had it from about 1992 to 1996 and then traded it off for some other gear. Sound wise I liked it at the time because it was quite punchy and it worked well for the finger style Jazz Funk Fusion that I was using it for. It worked well for busy syncopated staccato Bass playing .

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