TB+ construction question

Ken · February 17, 2024, 09:46:23 AM

Is the chunky rectangular part at the bottom of the TB+ a magnet? If so, what part does that play compared to the coils? I ask partly because the vintage pickups don't have that.

gearHed289 · February 17, 2024, 10:34:24 AM

I'm kind of curious about this too. The TB+ in my '94 Les Paul, also a pair I bought off eBay, AND the chrome guitar-sized ones on my Fenderbird look exactly like these on the bottom.

exiledarchangel · February 17, 2024, 01:04:14 PM

Yes, it is the (ceramic) magnet, or better, magnets, since there are 3 (one big between the two blades and two narrower outside).
The vintage Tbirds have alnico magnets instead of steel blades, so no need for a magnet on the bottom, thats one of the reasons they don't need as much cavity depth as the modern ones.

Ken · February 17, 2024, 01:08:21 PM

Thank you! I think I see the three you're talking about side by side in the one without the sticker? What's the copper (?) tape ( ?) across them for?

exiledarchangel · February 17, 2024, 01:16:12 PM

Exactly, the copper is used to ground the steel blades.

Ken · February 17, 2024, 02:43:34 PM

Thanks a lot. This puts a lot in perspective. As far as the difference in depth between the ceramic and alnico, is alnico just smaller? Why does the ceramic have to be so chunky?

exiledarchangel · February 17, 2024, 03:33:24 PM

It is because alnico is both the blade and the magnet, on the other hand steel needs an external magnet.

Ken · February 17, 2024, 03:44:51 PM

Is it not possible for the ceramic magnet to be a blade?

Alanko · February 17, 2024, 04:34:21 PM

Having, err, smashed one of these pickups out of frustration (an epoxy potted humbucker that is microphonic and prone to interference, how did Gibson f*** this up so badly?) the black rectangle on the back is a pad of epoxy over the copper tape that the coils and magnets are housed within.

exiledarchangel · February 18, 2024, 06:29:35 AM

Quote from: BklynKen on February 17, 2024, 03:44:51 PM
Is it not possible for the ceramic magnet to be a blade?

It is possible I think, the problem is that this pickup would sound very trebly. Iron in a pickup core gives it warm sound (alnico contains more iron and other ferromagnetic metals than ceramic magnets). Think of it like a recipe, too much salt and you are ruing it, everything must be balanced

Ken · February 18, 2024, 10:39:25 AM

Got it! Thanks so much. I'd love to have been in the room when they decided to go this route with the Thunderbird pickups. I guess the goal was a more "modern" sound than alnico gives. I like the TB+ a lot, but the construction seems way less elegant than the alnico ones.

Dave W · February 18, 2024, 06:13:45 PM

Quote from: BklynKen on February 17, 2024, 03:44:51 PM
Is it not possible for the ceramic magnet to be a blade?

Ceramic magnets are brittle. A ceramic thin enough to be used as a blade would almost surely break with the tensioned wire wound around it.

exiledarchangel · February 19, 2024, 12:39:11 AM

True. Also a ceramic blade so thin maybe is prone to demagnetizing.

Ken · February 19, 2024, 10:56:21 AM

This is all great info, guys. Thanks.

exiledarchangel · February 19, 2024, 01:02:25 PM

I mean, if there was a way to do it, since it is cheap (ceramic is cheaper than alnico), our friends from the exotic east would have found it and produce it in millions...