Dead Joe Barden HB Two/Tone, Low-Z Experiment?

[charrich56]

Everyone,

First post here so here goes, thx in advance:

I have been itching to wind and experiment with making a low-Z humbucker and have HUGELY appreciated the great posts and tips so far on this forum.

I started out by stripping an old GOTOH PAF to start, but sort of by accident I blew up a Joe Barden HB Two/Tone (rhythm PU thank goodness) because his old pickups used FLEA CLIPS instead of eyelets to terminate the coil windings, and the clip motion broke one of the coil wires when resoldering to extend the cable. I couldn't save the winding so cut and stripped the pickup.

Does anyone want specs or pics of the innards of this blade style PU? I don't have an inductance meter yet (plan to get one) but can share dimensions, photos, and approximate DCR for the tap points on this PU. I have the bridge PU intact and can do measurements on that as well.

I plan to rewind this PU with 32 gauge to start and use a Z matching transformer, then moderately preamp that. I would like to experiment with trying to duplicate the tonality switching features if possible in low Z.

The only low-Z pickup setup out there that is even close to what I would like to try to do with a low-Z Two/Tone is the Gibson Les Paul Recording/Triumph bass, which features taps on both coils of a humbucker, with switching that connects together the taps on both coils a la Two/Tone.

It would be interesting to play with this and see if the switch in tonality (humbuckerish/single-coilish) is possible with a low-Z pickup. I am going to try different reactances (R's and C's) on the low-Z side , before the xformer, to see if I can get typical humbucker and single-coil resonance peaks. I am going to use the old Gibson LP Recording and Professional/Personal schems for jumping off places.

I currently have an original set of Les Paul Signature pickups and stock wiring harness /controls that I put in a Ventura ES-330ish mutt guitar; that was what got me onto this low-Z bug.

Of course, if someone out there knows pretty down cold EXACTLY how the Joe Barden Two/Tone works (and it does work pretty well IMHO) an edifying explanation would be fantastic. I am even game for a discussion of how it probably works.

The puzzler for me is how this thing either gets or sounds like it gets, a narrow aperture (single coil width) sound, while still being a humbucker construction with two rails at normal polepiece spacing.

TIA,

Charlie

[David Schwab]

Does anyone want specs or pics of the innards of this blade style PU?

I do! I play with a guy that has two on his '74 LP Custom. They sound pretty good.

Does it have three coils? My understanding was it gets switched into a single coil mode with a dummy coil.

I used to make low Z bass pickups. I didn't use a transformer, but just ran them into a JFET booster.

I always wanted one of those LP recording guitars. It's a shame that people changed out the pickups in some of them.

[edit]

It must have three coils. Here's the wiring diagram for the regular HB which has 4 wires, and the HBTT which has 6 wires. Two wires per coil.

http://www.joebarden.com/Products/Wi.../HBandHBTT.pdf

[charrich56]

David,

OK, I will try to get together what I have for you, will post the DCR for both bridge and neck in a day or so (kinda late tonight) so we can figure out the tap point. The Two/Tone has a coil tap point on each of the two coils. Each tap is at about 60% of full windings. The "coil tap" or "mode" switch connects either the ends of the coil windings together, so the full coils are used exactly as a standard humbucker, or connects the tap points together, which bridges the taps and bypasses about 40% of the windings.

Looks like Gibson is doing the same thing if you look at the LP Recording/Triumph Bass schematic. But Gibson is using more tap points and using a rotary switch to bridge the taps of the two coils together.

The other notable, remarkable thing about the Joe Barden pickup is that there is less steel in this thing than any other humbucker I have ever seen. The two small, thin blades are pretty much it. The rest of the pickup (besides wire of course) is phenolic and some nylon-looking plastic. There are four non-magnetic SS screws which hold the baseplate/mounting ears to the bottom of the PU.

The interesting part is how Mr. Joe got what should only be an underwound humbucker (when switched) to sound darn near EXACTLY like his single-coil size Strat Deluxe pickups, with good volume matching between modes, and sounding really good in both modes. I can dig how lowering the effective windings/turns reduces the inductance and moves the resonant peak up, but there has got to be something else going on to make this work so well.

What I would like to get to is whether the tone and characteristics of the Two/Tone are intimately tied into the high-
Z part of the equation or whether the basic magnetic design and switching of the coils will allow this to work OK when I do a low-impedance version. The fact that Gibson went to all the trouble to do something similar in the Triumph/LPR bass is pretty tantalizing. Should be fun to find out.

-Charlie

[David Schwab]

Ah, a tapped pickup... now that makes sense from looking at the switch.

[charrich56]

David,

Here's the info on the PU's. I have photos at Flickr of both the lead (assembled) and the disassembled rhythm PU:
Joe Barden HB Two/Tone Pickup - a set on Flickr

Color codes:

WHITE - WHT - end winding coil # 1
WHITE w/stripe - W/S - tap point coil # 1
BLACK - BLK - start winding coil # 1

RED - RED - end winding coil # 2
RED w/stripe - R/S - tap point coil # 2
GREEN - GRN - start winding coil # 2

The coil starts and ends may be reversed, but I think this is right for a couple of reasons.

DCR:

Rhythm PU - each coil measures 4.14 K. From the coil start to the tap is 2.37 K and from the tap to the coil end is 1.77K.

Lead PU - each coil mesaures 4.74 K. From the coil start to the tap is 2.26 K and from the tap to the coil end is 2.48 K.

It's interesting that JB is using two different tap points on the lead and rhythm PU coils. These were purchased by me in 1999 as two separate boxed PU's but are the same vintage and shipment to the dealer.

So here's the head scratcher - when in tapped (single-coilish) mode, do the parts of the windings which are connected together at the tap point but unconnected at the other end, contribute in any way, electrically or magnetically, to any of the electrical characteristics or the shaping of the magnetic field of the pickup? Sure would like to get a couple of smart heads, of which there are many in this forum, to think about that.

-Charlie

[Electricdaveyboy]

Maybe he uses different wire gauges, so the DCR on the Lead Pickup is lower but output and tone is fatter because the wire is bigger.

[David Schwab]

I don't know how I missed this follow up back then... thanks for the photos. Too bad you didn't use macro mode on the camera though.

Kind of of how he uses two magnets.

I think he's using the same gauge wire, and just voiced the two pickups differently. I think the smaller values are the ones being used when it's in the single coil sounding mode.

I'll assume the OP hasn't been back here, since he only posted 3 times, but the unused coil tap shouldn't affect the tone unless it's made into a closed loop.

[Electricdaveyboy]

I got parts made for blade pickups but in the beginning I had a Rail Humbucker for Metal sounds in mind.But I try experimenting with the 2tone idea a bit ,too.

[David Schwab]

Those look good.

[RAB Custom]

Hey Charlie, I'm new here and was reading your wanting to find out about Joe Bardens pickups. I found what the inductance is on The humbuckers at warmanguitars.com. He has quite a list on most pickups and their resistance and! inductance. Joe winds them at around 4.11 to 4.25 and with a inductance of 6.50H (inductance) H means henries. What I can't find is his wire gauge size and number of turns and what coating he uses on the wire. He does have ceramic magnets in them I was told by another tech. If you can measure the wire gauge I would love to find out what he uses let me know. E-mail me at randybiangardi [AT] comcast [DOT] net .

[David Schwab]

Hey Charlie, I'm new here and was reading your wanting to find out about Joe Bardens pickups. I found what the inductance is on The humbuckers at warmanguitars.com.

Your link is wrong, it's Warman Guitars - comparison of various electric guitar pickups and output

Keep in mind you are replying to a 4 year old post by someone who only posted 3 times. I doubt he saw this.

[Electricdaveyboy]

Just rewound a Barden Tele Set.