[BOBBO]

I thought it might be a good idea to try and compile as much information on PAF's in one place as possible for the forum to learn from !! Please feel free to contribute any info you have on original PAF's !! To start it off , I found a good website with alot of PAF facts and history as well as some cool pictures !! Please take a look !!






Gibson PAF Humbuckers Pickups Patent Applied For Pickups M69 M-69 pickup rings - Vintage Guitars Info

Gibson PAF Humbuckers Pickups Patent Applied For Pickups M69 M-69 pickup rings - Vintage Guitars Info


Here is some of the info from the website !


Because of the amount of "bogus" PAF (Patent Applied For) Gibson humbucker pickups out there, I was asked to create this web page (thanks to GW Dean and BurstMeUp for information and pictures). This web page includes information on the pickups themselves *and* their plastic mounting rings. The originality of the pickups and their mounting rings are both important factors in the integrity of a vintage Gibson guitar.
There are some basic facts that should be known about these first-generation humbucking pickups. First PAF pickups came about in 1956 on Gibson steel guitar models, and on 1957 on many Gibson spanish guitar models, and lasted to about 1962 to 1965. Nickel plated part models transitioned away from PAF pickups first around 1962, since these guitars were sold in greater numbers. Gold plated part guitars can often be found with PAFs (or one PAF and one Patent# pickup) as late as 1965. PAF pickups of course have two internal coil bobbins under a 1.5" x 2.75" metal cover with one bobbin having a row of six adjustable slot-head poles, and the other bobbin being non-adjustable.

PAF History.
I guess we should start with a little history of the Gibson PAF pickup. By the mid-1950s, Gibson wanted to counter the latest electric guitars introduced by Fender. Leo Fender had built a company that was a sizable competitor in the solid-body guitar market place. Gibson believed they could beat Fender with their high quality Les Paul, and by developing a low-noise pickup.

The problem with Gibson's P-90 and Fender's single-coil pickups was inherent in their designs, allowing 60-cycle hum (noise) to interfer with the sound. Seth Lover was the Gibson engineer assigned to solve the problem. Seth connected two single coil pickups in series (opposed to parallel) and connected the coils out-of-phase electrically and magnetically. Thus the signal noise of each separate coil canceled out the noise of the other coil. That is how the pickup came to be known as a "humbucker".

Seth/Gibson filed their patent for the pickup design on June 22, 1955. Gibson added the new pickups to steel guitars in 1956, and in 1957 on electric solid-body and arch-top guitars including the Les Paul Model. During late 1957, a small black decal with gold lettering was added to the underside of the pickup that read, "PATENT APPLIED FOR" (hence the PAF abbreviation).

Seth Lover received his pickup patent #2,896,491 on July 28, 1959. By mid to late 1962, Gibson changed the pickup decal to read, "PATENT NO 2,737,842". Interestingly the patent number listed on the decal was not for Seth's pickup design but was for Les Paul's trapeze tailpiece! Perhaps this was a research roadblock for the competition, or maybe just a mistake?

PAF Magnets.
From 1956 until 1961 Gibson used different Alnico magnets in their PAF pickups. Alnico magnets (alloys ALuminum, NIckel, and CObalt) come in a different grades based on their magnetic strength. Gibson generally used the same magnets (size/grade) which was available for their P-90 pickups. But Gibson randomly used Alnico 2,3,4,5 grade magnets in PAFs until 1961 (remember the higher the magnet's number, the higher the magnetic strength). This can often account for how two PAF pickups can sound quite different. In July 1961 Gibson began consistently using a smaller Alnico 5 magnet (smaller as in the flat top side of the magnets were smaller lengthwise). The original length was 2.5" long, which was decreased to 1/8" long in July 1961. But the "short magnet" PAF can be seen here and there as early as 1960 and is still original. Just from a consistency point of view, July 1961 is the date considered by most as when short magnets were the norm for PAFs. Generally speaking decreasing the flat side size decreases the power of the pickups, but this was somewhat counteracted by the Alnico 5's added strength. So do short magnet PAFs sound better or worst than 1957-1960 long magnet PAFs? NO. In fact, they may sound better in many cases.

Dimensions of PAF magnets follow (measured using a micrometer, and obviously this will vary a bit from magnet to magnet): 2.509" long ("long magnet" version), .506" wide, .131" thick. The "short magnet" PAF length was the a bit different: 2.371" long, .491" wide, and .121" thick.

Pickup Wire and Winding Methods.
The pickup were wound with #42 plain enamel wire. On original PAFs the bobbin wire appears purple, versus later PAF and patent# pickups that appear reddish. Gibson eventually switched to polyurethane coated wire around 1963. When wire coatings change, the sound of the pickup does change, contributing to the PAF following. The amount of wire (and coating) wound on each bobbin determines the pickup's resistance. When the bobbins are wound with more than a nominal amount of wire (either on purpose or by accident), they are more powerful with fatter midrange but less treble. Due to the human factor and the wide tolerance of the manually-run pickup winding machines used by Gibson from 1956-1961, PAF pickups usually measure between 7.5 and 9.0 thousand ohms (K ohms). By 1962 (the end of the PAF era), Gibson was making pickups very consistently with 7.5k ohms of wire (give or take .25k ohms).

The separate bobbins of a PAF can measure very differently due to Gibson's manufacturing techniques. For example one bobbin could measure 3.5k, and the other 4.5k ohms (for a total of 8k ohms). This mis-matched ohms is actually a good thing, as certain frequencies will stand out if both bobbins have different resistance. This contributes to why two PAF pickups can sound quite different.

Around 1965 to 1968 (exact date unknown), Gibson changed from a manually-run pickup winding system to a fully automated system. Because of this their humbucking pickups all became a consistent 7.5k ohms from 1965 and later. The manual-run system had a machine operator that decided when a pickup bobbin reach about 5000 turns of wire. So there was plenty of room for under and over-winding. When the fully automated system came into place, the pickups were very consistent in their windings (and hence total ohms).

Gibson Models which Used PAF Pickups.
The 1957 to 1962 Les Paul Standard model is probably the most famous of the models to have PAFs pickups, though other models had them too. Like the ES-175, ES-295, Byrdland, ES-350, ES-5 switchmaster, L-5CE, the Super 400 and the ES-335/ES-345/ES-355 (when introduced in 1958/1959).

Jazz Guitar PAF Versions.
The hollowbody jazz guitars often used a slightly different PAF in the neck position which had different (narrower) string spacing, where the bridge position jazz PAF was identical to the neck & bridge PAF in say a Les Paul Standard. The models that used this narrow spacing neck PAF was the Byrdland, ES-350T, L-5CE, S-400CE and some Barney Kessel models. The distance on a narrow PAF from center to center of the two "E" adjustable poles is 1 13/16", compared to 1 15/16" on the "normal" spaced PAF pickup. Also since most of these models had gold plated parts, the narrow spaced PAFs would be gold plated (except on some Barney Kessels). If the pickup cover is removed from a narrow spaced PAF pickup, the "normal" pole position tooling marks can be seen on the narrow spaced PAF pickup.