Firebird PU small metal top plate - necessary?

[rjb]

But does the ferrous plate do not increase the magnetics field around itself as a Tele bridge pickup?

I dunno. Post #2 is still my best guess.

-rb

[charrich56]

I dunno. Post #2 is still my best guess.

-rb

The response from the Stew-Mac guy sounds like the opposite of what one would expect by partially "shunting" the magnetic field under the B string with the piece of metal, and reducing output. I do appreciate the asking, though.

BTW just as an aside, the GFS Gold Foil P-90 humbuckers actually look like a classic Firebird HB design (minus the little metal piece in question) when one peeks under the gold foil on top. Also, the "polepiece" screws are probably stainless and definitely non-magnetic, as verified by my Spin Doctor gaussmeter, therefore they are there completely for looks. The polepieces aren't necessarily bad, I'm just commenting on what they are. I'm going to throw my set into an Epiphone I have handy, with a variable rez tone control, and see if they can make good sounds.

[marcfrom]

I dunno. Post #2 is still my best guess.

-rb

Especially the "Try it".

Somebody else has an opinion ?

[rjb]

Somebody else has an opinion ?

To put it undiplomatically, my opinion is that the Stew-Mac guy is all wet.
So far, there seems to be a consensus about the purpose of the piece of metal, if not about the Stew-Mac guy.

-rb

[rjb]

BTW just as an aside, the GFS Gold Foil P-90 humbuckers actually look like a classic Firebird HB design (minus the little metal piece in question) when one peeks under the gold foil on top....

As an aside from the aside, the GFS Gold Foil Alnico V (non P-90) humbuckers are built like "regular" humbuckers, with bobbins of the same dimensions. DCRs of 5.4K (neck) and 6.0K (bridge) of 43AWG puts them in the ballpark of 3000 turns/coil. I know because GFS is phasing out the 4-conductor fixed solder leads and replacing them with 3-conductor detachable leads; I wanted the option of wiring the coils in parallel, so....

I'm going to throw my set into an Epiphone I have handy, with a variable rez tone control, and see if they can make good sounds.

By "variable rez tone control", do you mean a rotary switch with a bunch of capacitors?

-rb

[copperheadroads]

The response from the Stew-Mac guy sounds like the opposite of what one would expect

I've had conversations with them ....Trust me they are not winders .

[rjb]

It seems we're approaching a consensus about the Stew-Mac guy...

[charrich56]

As an aside from the aside, the GFS Gold Foil Alnico V (non P-90) humbuckers are built like "regular" humbuckers, with bobbins of the same dimensions. DCRs of 5.4K (neck) and 6.0K (bridge) of 43AWG puts them in the ballpark of 3000 turns/coil. I know because GFS is phasing out the 4-conductor fixed solder leads and replacing them with 3-conductor detachable leads; I wanted the option of wiring the coils in parallel, so....


By "variable rez tone control", do you mean a rotary switch with a bunch of capacitors?

-rb

Even better. I use a buffer to bootstrap a capacitor through a pot, and can continuously vary the load capacitance, therefore the pickup resonant frequency, over more than 1 1/2 octaves. Beats the pants off a regular tone control. The buffer allows independent setting of pickup load resistance to control Q. It works very nicely. Here's the thread on it: http://music-electronics-forum.com/t43081/

The "variable rez tone control" really stands for "variable resonant frequency tone control." I don't have a cuter name for it yet.

I designed an open-sourced 2-JFET buffer that works well with this approach. It's close to the end of the thread. There will be a commercial SMT version of this buffer very soon.

-Charlie

[Zhangliqun]

Regarding the original question: FWIW, I've made them both ways and I can't hear a difference so I stopped bothering with it.

[jrdamien]

This is the answer of Peter Schultz from Stewmac

Thank you for contacting us. The small steel plate across the top of a Firebird Mini Humbucker helps to focus the vibrations of the "B" string. This causes the "B" string to have a slightly higher output relative to the other strings.

Using one of these Firebird Mini Humbuckers, you will notice that the "B" string sounds more compared to the other strings. This small steel plate is part of the vintage technical specifications that contribute to the vintage sound of these pickups.

Ummmm...

Of all of them I have made, the only difference has been that the field is shunted on the B & G strings. I now make them without.

I just did a bridge FB for a guy and he wanted it "pure vintage" so I cut and applied the little plate. He called back right after picking it up complaining there he couldn't here the B & G string as well.