The second series EB3 schematic applies to EB3s from late 1971 until 1979. In general series 2 circuitry can be identified by the black cylindrical choke - identical to the one employed on the Ripper, and new-style capacitors.
Pots used were initially two 500K volume pots (unknown taper) (part 70027) and two 250K audio taper tone pots part 70021. These were the pots listed in the 1971 and 1977 parts lists. The 1981 parts list changes these to 300K (linear/special audio taper) 70028 volume pots and 100K audio 70035 tone pots. In each case capacitor and choke values are unchanged.
These part lists (and instruments examined) clearly differ from the schematic shown (300K volume, 250K tone), and it is probable that all three circuit variants exist, and furthermore the precise potentiometer values are not terribly significant in the operation of this circuit, as long as they are matched.

Functionally series 1 and series 2 circuits are very similar - the main difference being the tone choke is activated in position 1 in series 1, and position 4 in series 2.
The image shown below shows a very early series 2 schematic, from an early 1972 EB3, with two 70027 and two 70021 pots

See the series 1 EB3 schematic
Gibson EB3 bass for sale
Gibson EB-3 FRETLESS Bass Guitar Electric Vintage Rare 60??s / 70??s SG Fret Less
Brisbane, California, 940**, UNITED STATES OF AMERICA
$1799
-11 pounder
-nics and dents everywhere, wear here and there. Belt rash
-extra hole from a once moved strap peg
Ive had this for a few years. Im just not a fretless player, but I always dug this thing. Was in this condition when I originally purchased it. Pots look original
Switch #4 and #1 light ... more
1969 Gibson EB3 Bass Guitar- 100% Original with Original Case
Glastonbury, Connecticut, 060**, UNITED STATES OF AMERICA
$3700
Gibson EB-3 Cherry Mod 1969 Electric Bass Guitar Original Case Slotted Head Art
El Segundo, California, 902**, UNITED STATES OF AMERICA
$3500
... more
Gibson EB-3 Bass Guitar
Santa Barbara, California, 931**, UNITED STATES OF AMERICA
$1800
1972 Gibson EB-3 Slotted Headstock Vintage Short Scale SG Bass Walnut w / Case
Seattle, Washington, 981**, UNITED STATES OF AMERICA
$2900
Surprisingly versatile, the EB-3 delivers warm, midrange rich snarl from the mini humbucker in the bridge position, and powerful low end thump from the neck position "Mudbucker " The rotary pickup selector offers a bevy of tones at the flick of a ... more
"1973" Vintage Cherry "GIBSON EB-3" with OHSC Serial #056076 in Great Condition
Riverside, California, 925**, UNITED STATES OF AMERICA
$3295
1972 Gibson EB-3 Short Scale Electric Bass Walnut Finish SG Vintage Gig Bag
Astoria, Oregon, 971**, UNITED STATES OF AMERICA
$1995
1961 Gibson EB-3 the cleanest original extent w / hang tags 1 of a kind & Minty !
Fort Lauderdale, Florida, 333**, UNITED STATES OF AMERICA
$11495
1971 GIBSON EB 3 SLOTTED HEADSTOCK BASS CASE - Made in USA
COLOGNE, GERMANY
£385
* CASE ONLY !
* interior has stains
* tolex has rips
* all latches are working fine
* worn but solid
* check all pics
... more
Gibson EB-3 Bass Guitar 1967
Horncastle, LN9***, UNITED KINGDOM
£2950
1971 GIBSON EB 3 SLOTTED HEADSTOCK BASS CASE - made in USA
COLOGNE, GERMANY
€444
* CASE ONLY !
* strap that holds case open=GONE
* bottom and top are loose =need reglueing
* tolex has rips
* all latches are working fine
* check all pics
Over 1000 more
GUITARS-BASSES-PARTS in our OTHER
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TAKE A LOOK !!!... more
1971 GIBSON EB 3 SLOTTED HEADSTOCK BASS CASE - Made in USA
COLOGNE, GERMANY
£385
* CASE ONLY !
* interior has stains
* tolex has rips
* all latches are working fine
* worn but solid
* check all pics
... more
Gibson EB 3 CASE 1971 - passend für NUR GESCHLITZTE SPINDELSTOCK-Version
COLOGNE, GERMANY
£399
* CASE ONLY !
* strap that holds case open=GONE
* bottom and top are loose =need reglueing
* tolex has rips
* all latches are working fine
* check all pics
* SOLD AS IS - NO RETURNS... more
1971 GIBSON EB 3 SLOTTED HEADSTOCK BASS CASE - made in USA
COLOGNE, GERMANY
€439
* CASE ONLY !
* interior has stains
* tolex has rips
* all latches are working fine
* worn but solid
* check all pics
PLENTY of PARTS for SALE
ATTENTION! OVER 1000 more
GUITARS-BASSES-AMPS-PARTS
in our OTHER AUCTIONS !!!
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