Adding a ceramic bar magnet to alnico rods

[GlennW]

I have a single coil P-bass style pickup with rod magnets and I'm not crazy about how it sounds. I want to see how it'll sound after adding a ceramic bar magnet, since that would be easy and I'm curious.

I don't know much about magnets, but have read that you shouldn't slide them across one another. Are there any precautions other than just sticking the bar magnet straight onto the bottom of the pickup?

It's not a HB magnet, north and south are on the wide part.

[David King]

You can make dramatic changes by just sticking a chunk of steel across the bottom of the alnico rods. I wouldn't worry about demagnetizing them with a ceramic magnet but you might want to try combinations of whatever stuff you have handy to see if you can get some improvement.

I had a set of Fralin J pickups that I tried this with and they only sounded worse.

Gluing the ceramic bar on where it's trying to repel the alnicos makes a lot more sense to me.

[GlennW]

Gluing the ceramic bar on where it's trying to repel the alnicos makes a lot more sense to me.

Reverse psychology? What would having the magnets like that do? Seems like it would make it weaker.

Since there doesn't seem to be a large risk I'll try just sticking it on the bottom first.

[Dave Kerr]

You could always try sticking a cheap neo disc to the bottom of one, all, or several pole pieces for a few pennies each.

[GlennW]

Thanks, Dave. Those look very promising, and the price is nice.

[GlennW]

Just tried it with the addition of the Peavey bar magnet.

I like it, might be imagining things, but it seems to add a little on the attack and make it sound less muddled. Whatever happened was an improvement.

Since nothing exploded, I'll try it later with the addition of two bar magnets because there's room and I want to know.

Edit: won't be adding another bar magnet. It seems to have more treble than before, which might explain the extra clarity. The bass has a cap switch without a pot and the lower values are more clackety than before, so I'll leave it as is for a while.

[David King]

Hmmm, did I get that wrong? Sorry.
Well it might be interesting to know if it makes a dramatic change in the tone...

[Mark Hammer]

Didn't Alembic use to market a sort of "performance booster" for Strat pickups in the way of retrofit magnets that were supposed to sit under the polepieces?

[GlennW]

Don't know if they did or not.

I'm going to rewind this pickup. It's a Jay Turser SCPB, north, ccw, 7.15 K.

After adding some wire it could be switched from 7.15 to 8.85 K. That didn't do much because 7.15 with a .047 uF cap doesn't sound very different from 8.85 with a .033 uF cap, it's like that throughout the range, close to a difference of one position on the cap switch. It sounded alright, but nothing special. The cap switch works well and goes .022, .033, .047, .069, .1 uF.

After adding the bar magnet it sounded better in some ways, but sort of hi-fi. Time for Plan B.

I've decided to add a Muy Grande Jazz Bass bridge pickup which I like and is just setting in a drawer. It's north, ccw, 10.02 K, and I'll rework the SCPB to be south, cw, and around 9.5 K.