ikay

@goingdownslow can you explain what this mod does?

Here's an American Traditional headstock for comparison. The small decal at the top should read 'American Traditional'. The tuners in the original post look like they've been upgraded to vintage tuners with straight posts. In the neck pocket, above the S47843 there's a faint date stamp - looks like 1999 which would tally with the N9 serial number.

Having dug a bit deeper you may actually be right 😮. The adjustable pole pieces on newer Rics (2007 onwards) screw through the bobbin into the magnet. I found a pic of a disassembled bobbin and you can clearly see that the holes in the magnet for the pole pieces have been drilled at a slight angle. So when assembled the bobbin will look on the wonk. The holes used to screw the bobbin/magnet assembly to the baseplate are over-sized so there should be a bit of wiggle room to straighten things up by loosening these off and repositiooning. The magnet would then be on the wonk but that could be covered by a bezel. On pre 2007 pickups without adjustable pole pieces, the bobbin was just glued onto the magnet. Some of these were also wonky so whichever way you look at it it's not exactly a precision assembly job!

Same as my old Zon Legacy fretless which I bought from John Giblin. Used by JG on various recordings with Kate Bush and Scott Walker, even a James Bond score. I was anticipating a dramatic improvement in my fretless playing but sadly not!

Yes I looked at the bezel but even with that you can still see the pickup is slightly on the wonk! It's just sloppy assembly which is pretty bad for such an expensive bass. I don't actually have a 4003 yet BTW but have my eye on one and this is putting me off!

I've noticed that some 4003 bridge pickups aren't quite square on the caddy which my OCD finds hard to deal with. How is the bridge pickup attached to the baseplate and is it an easy job to straighten it up?

1957 P. Possibly touched by the great man himself. (I don't have that in writing 😁)

Mex pot shafts are slightly too big for a typical metric knob (not too small).

There quite a few on ebay UK. Not sure about ebay Spain but worth running a search for 'Stratocaster knob imperial'.

For around 400Euro the Bach BRBB comes quite close to a Laredo/Cheyenne ... http://www.bachmusik.com/en/music-instruments/bass-guitars/model-bach-brbb

That would be interesting, give it a go! For 30" scale (762mm) the Stingray pickup position should be 303mm from the 12th fret to centreline of the pickup. Bear in mind that the Bronco in standard form has 18mm string spacing, but the neck is just about wide enough to take a regular 19mm bridge. I think the Kent Armstrong has full width bar magnets so that should work with any string spacing.

Fender Ultra P + J also have compound radius boards (10" to 14"). Plenty of other basses out there with compound boards.

Are you sure the pots are 473k? The pic above shows the number 473 on the tone cap which signifies a 47nf cap (a standard value). Or is that just a coincidence?!

The Delano pickups should have plenty of top end. What are the pot values? If they're 250k you could try changing them to 500k which would brighten up the sound.

Just sold my Boss RC-3 looper to Russ. Top chap, quick to respond to messages and a pleasure to deal with. Happy looping!

No, tightening the truss rod gives you less relief, slackening it off gives you more relief, see diagram below.

How it affects the solo'd P sound depends on how it's wired. If a P/J is wired as a regular VVT then the additional vol pot will change the load on the P pickup which does affect the tone. In the same way that swapping 250k pots for 500k makes the sound brighter, adding an extra pot (in parallel) reduces the load and makes the sound a little less bright. Soloing the P pickup in a VVT setup will sound similar to running a standard P with the volume backed off a bit. A smidge less grunt. You might not notice it unless you really listen for it but it does make a difference.

This TB thread is about a similar problem - https://www.talkbass.com/threads/peavey-millennium-bxp-ac-preamp-cuts-out-when-treble-control-turned.1098452/ What make of bass is yours? As a first step it might be worth giving the iffy pot a squirt of contact cleaner to see if that makes any difference.

It would also be possible to add a switch to completely remove the added J pickup (and vol pot if it has one) from the circuit allowing you to switch between a P/J config or the original unmolested P config.

This article on fixing a B2A with dodgy wiring contains a wiring diagram which might be useful - https://richsstudioproject.wpcomstaging.com/2015/08/19/hohner-b2a-active-electronics-repair/

Crikey, that's a bit of jumble!

Have you tried tweaking the trim pots for the mid control in the control cavity? You can adjust the mid freq and the level of cut/boost if you're not happy with the factory settings. Might be worth having a play with that before replacing the preamp.