The Pickup Line, Part 2
This should illustrate the difference between enamel coated wire (top) and poly coated. There is some color variation bwteen different manufacturers but they're pretty distinctively different.
OK, I’m assuming you read Part 1, so I’ll pick up (get it?) where I left off. So, it’s 1965 and the covers have gone from nickel to chrome but what’s going on underneath? It turns out that poly coated wire is cheaper than enamel coated and, Gibson, being interested in making more money, makes the switch. Poly coated wire is kind of orange while enamel is purplish brown (and varies a good bit). There are those who perceive a difference in tone between the two but I rarely get the chance to do a side by side so I can’t comment since most of the guitars I get are 65 or earlier. Trying to describe pickup tone is a quagmire anyway, so we’ll skip it. Anyway, the poly wire patent numbers seemed to have shown up about the same time as the chrome covers-some time in 65. Research will tell you that T-tops showed up in 65 as well but I don’t think they did. I’ve never seen a T-top in a 65 ES model or SG. I don’t get to see a lot of later guitars but every 66 and most 67’s I’ve had have had poly wound patent numbers. I’m speculating that T-tops really showed up in late 66 or early 67. It must have been a pretty long transition because I’ve seen the pre T-top patent numbers as late as 1970. Another fairly consistent feature of the later patent number (pre T-top) is the color of the wiring. PAFs and early patents had two black wires connecting the bobbins to the lead wire. later poly wound patent numbers (and T-tops) have one white and one black wire. What exactly is a T-top? A T-top is, essentially a redesign of the patent number pickup that addressed a few problems and probably saved Gibson some money. The biggest change is the bobbin itself. The embossed “T” in the top is supposed to be so that the winders can orient the pickup in the right direction. It’s basically a “this end up” symbol. The little “square in the circle” hole through which you could see the windings also disappeared. T-tops lasted well into the 80’s although the sticker was replaced by an embossed patent number in the base in 1976 or so. Another dilemma…how can you tell what’s under the cover? You can’t unless you remove the cover which hurts the value of the pickup. There is a way to improve your odds of getting a pre T-top over a t-top in a chrome covered pickup. Look at the bobbin screws on the bottom. If they are slotted, chances are good that it’s a T-top. If they are phillips, then it’s a crapshoot. Slotted screws are rare on a pre T-top but phillips are not uncommon on T-tops. meaning if it’s slotted it’s probably a T-top. If it’s phillips, it could be either. Not much help, huh. Most players prefer PAFs to patents and patents to T-tops and the market reflects that. Is there a difference in tone? Yes, but there’s a difference in tone between two PAFs as well. You’re best served to listen to any pickup rather than looking at the sticker. Any general discussion of pickup tone is bound to elicit comment and controversy. When you start getting into long magnet vs. short, late PAF vs. early patent number, enamel vs. poly or late patent vs. t-tops, you’ll get very little agreement. I could also argue that I’ve heard plenty of boutique “PAF” pickups that sound wonderful. That little PAF sticker may add a thousand bucks or more to the price but it doesn’t make the pickup sound any different. The change in wire from enamel coated to poly does change the sound so perhaps that is the more important thing to look for. My opinion? So glad you asked. The best value and most consistently good sounding pickups are early patent number with enamel windings. They’ll cost half of what a PAF costs and you have an excellent chance of getting a great pickup if you can’t hear them before buying. If consistency were the only criterion, then the T-top would be at the top of the list. Nearly all of them read out at 7.5K ohms or so because of the automated winding machines in use during the era. Most everyone thinks the “magic” in the earlier pickups is a happy accident borne of the early winding machines which had no counters or automatic shutoff. Guys like Seymour Duncan, Jeff Shepard (Sheptone), John Gundry (Throbak) and Jim Rolph have been chasing (and catching) the “happy accident” for years. The results are out there for you to try. One last point. The timeline postulated here is for nickel and chrome covered pickups. The gold covered ones have a somewhat different (and tougher to pinpoint) trajectory. Later.
It's called T-top because of the "T" embossed into the bobbin (duh). Supposedly, it was there to tell the winders which end was up. You can also see that the little window (square in the circle) isn't there on a T-top.
Yup, early patent # pups your best pickup value! Also I agree, use your ears in selecting a pup you like. The ohm reading is interesting but not very meaningful in terms of tone or loudness of the pickup! Keeping the cover on or removing it also changes the tone. Personally I keep them on even with zebra or double white PAFs. I always worry about potential damage to the delicate coil windings from snagging them with a pick edge, etc!
I’ve some great sounding pups in a ’68 ‘345. Unopened and I’m not going to open them. As you said just use your ears. Could be t-tops, late pat. no.s and maybe a small chance early pat. no.s. They have the Philips screws but that don’t mean much. ES-345 means unlikely they have been swapped. Look forward to your next instalment about the gold covered pups Charlie ! Thanks for the blog, really enjoy reading it !
I would bet real money that they are pre T-tops. Probably not early patents but it’s possible. One way to tell T-tops without removing the cover is by measuring the DC resistance. If it’s more than 7.6K, it probably isn’t a T-top. If it’s less than 7.4K, it probably isn’t a T-top. Almost all T-tops are between 7.3K and 7.6K. There are exceptions. I’ve seen them over 8K but its pretty rare. T-tops were wound by machines with autostops so they are very consistent in terms of DC resistance.
Great stuff as always! There’s one question I’ve been wondering a long time considering Pat. Nos. The story often goes: early one’s (1.) are like late Pafs and then the wire changes (2.) to poly and then comes T-tops (3). But are there any technical difference between No. 2 & 3 other that No. 3 has those T-markings (and maybe different bobbin screws and covers)? Or did Gibson got those automated winding machines during the T-top period that might make No. 2’s more special?
There seems to be much more variation in the late patents (pre T-top) which leads me to believe they were still winding them by eye and allowing for some accidental greatness. I don’t have the ”
official” story from anyone at Gibson.