Re: hb-1 pickup construction
Okay I took the covers off these pickups over the weekend and I must say...they sound WAY better with out them. In what way? They sound less compressed. I also found that these appear to be more sensitive to distance from pole piece to screw than some other pickups. Backing them down away from the strings made another large improvement in their sound. This is, of course, just my personal opinion re: what sounds good.
BTW, I could detect no difference between the bridge and neck pickups. The both measure at about 7.1k resistance.
One theory is that the strength of the magnets may contribute to this effect. In a thread on TGP, Joe Naylor indicated that weaker magnets may result in compression. I did some not-entirely scientific testing of magnetic force of the pickups before and after I removed the covers. As you might expect, after removing the covers the force was much more notable on the non-screw coils. The other thing one notes is that the hb-1 covers have a raised rectangular area over the non-screw pole pieces. This has the effect of keeping these pole pieces even further from the string than the screw pole pieces. This apparently makes the magnetic field weaker over these pole pieces. Removing the covers allows these non-screw pole pieces to generate a stronger magnetic effect on the strings. I also screwed the screw pole pieces deeper into the bobbin so that they kind of mimic the curvature of the neck.
Now, as for the hb-1 pickup construction, I didn't completely disassemble the pickups so there are some measurements I didn't get, but here are some measurements I did get that may come in handy for someone one day. First some pics:
They're constructed quite a bit like many Gibson humbuckers but I don't think the dimensions are not identical. You can see the magnet running down the center, on top of the baseplate, between the two bobbins.
Magnet (W x L x H): .5" x ? x .1 (didn't disassemble pickup so I don't know the len)
Bobbins:
- outer height: .351"
- inner height: . 243"
- width: .725"
- length: 2.59"
Base plate:
- width: 1.485"
- length: 2.709"
Height from top of base to top of bobbin: .5"
Pole piece (screw) length: .85"