Jeremy Spencer Guitars & Gear: Fleetwood Mac’s Slide Savage Complete Rig Guide

The Gibson ES-125 is the instrument most closely and most accurately associated with Jeremy Spencer’s Fleetwood Mac slide work — the guitar that produced the specific tone heard on the early Blue Horizon albums and on live recordings from 1968–1970. The ES-125 is a full hollow-body non-cutaway archtop — Gibson’s budget-range instrument introduced in 1941 and produced through 1970, positioned below the ES-175 and ES-330 in the Gibson hollowbody lineup. The mid-to-late-1950s ES-125 specification: a fully hollow laminated maple body with no cutaway, in either a full-depth body (the standard ES-125) or a thinline body (the ES-125T variant introduced in 1956), a 24.75-inch scale length mahogany neck with a rosewood fretboard and dot inlays, and a single Gibson P-90 soapbar single-coil pickup in the neck position. The P-90 in the ES-125 is wound to approximately 7.5k–8.5k ohms DC resistance with an Alnico V bar magnet (the P-90 uses a bar magnet under the coil rather than the rod magnets of the humbucker, giving a different flux pattern and tonal character), producing a broad, harmonically rich single-coil sound with pronounced midrange presence and a slight roughness at the top end that is entirely absent from humbucker-equipped instruments. The fully hollow body contributes significant acoustic warmth and a natural resonance that amplifies the P-90’s tonal character — the ES-125’s combined acoustic-electric quality gives the guitar a three-dimensional bloom on sustained notes that solid-body instruments simply cannot replicate. For slide playing — which Spencer performed with a metal slide on the ring finger of his right hand, playing in open tunings — the ES-125’s hollow body produced the acoustic sustain and natural feedback characteristics that Delta slide technique demands. The guitar’s relatively high action (set deliberately for slide clearance) and the P-90’s broad, forward-midrange character gave Spencer’s slide tone its characteristic rawness and presence.

The ES-125T — the thinline version of the ES-125, with a shallower body depth of approximately 1.75 inches compared to the standard ES-125’s approximately 3.25-inch depth — also appears in documentation of Spencer’s instruments. The thinline body reduces the acoustic hollowbody resonance somewhat compared to the full-depth model, giving a slightly tighter, more controlled tone that is less prone to feedback at high volume — a practical consideration for a live performance context where Spencer was working with cranked British valve amplifiers. The P-90 specification remains the same as the full-depth ES-125.

Vintage Fender Stratocasters appeared in Spencer’s setup alongside the ES-125, providing a completely different tonal palette for non-slide electric work. Early-to-mid-1950s Stratocasters — the slab-body, two-tone sunburst examples from 1954–1958 — used Alnico V staggered-pole single-coil pickups wound to approximately 5.8k ohms DC resistance on the neck and middle positions, with a slightly hotter bridge pickup at approximately 6.4k ohms to compensate for the position’s naturally lower output. The 1954–1958 Strat specification includes an ash body (brighter, more pronounced grain than the alder used on most post-1956 examples), a maple neck with a V-shape profile (the distinctive “Vee” neck of early Fenders, transitioning to a softer C-shape by 1957–1958), a single-ply white pickguard (eight-screw on 1950s examples), and the original three-saddle bridge with the “bent-steel” saddle design. The 1950s Strat’s tone — particularly the neck pickup — has a warm, almost hollow quality that comes from the Alnico V poles’ interaction with the ash body’s resonant characteristics, quite different from the brighter, more aggressive character of later ceramic-pole examples.

Telecasters — specifically early-to-mid 1950s examples with the original “blackguard” (black Bakelite pickguard) configuration — appeared in Spencer’s setup for the more rock’n’roll-influenced material, particularly the 1950s pastiche tracks on Kiln House. The original “blackguard” Telecaster specification: swamp ash body, maple neck with the original “skunk stripe” truss rod routing (Fender’s distinctive method of routing the truss rod from the back of the neck, filling it with a contrasting walnut strip), a single-ply black Bakelite pickguard, the original Fender No-Caster/Telecaster three-saddle bridge with two brass saddles (three strings each), and the original single-coil pickups. The bridge pickup on a 1950s Tele — wound to approximately 7.0k–7.5k ohms with Alnico III or Alnico V magnets depending on year — produces the most purely percussive, attack-forward electric guitar tone of any mass-produced instrument of the era, and its character is essential to the rockabilly and early rock’n’roll sounds Spencer was referencing on Kiln House.

For acoustic Delta blues slide work — both in the studio and in performance contexts where an amplified electric was inappropriate — Spencer used a National Style O single-cone resonator guitar. The National Style O specification: a fully metal body (nickel-plated brass on most production examples, steel on some variants) with an engraved chrysanthemum pattern on the body and F-holes, a biscuit-bridge single-cone resonator system (a single spun-aluminum cone with a wooden biscuit bridge sitting at its apex), a 12-fret neck joint, and a 24.75-inch scale length. The biscuit-bridge resonator system produces the characteristic National sound: a loud, metallic, percussive tone with a pronounced high-frequency component and a strong, penetrating midrange that cuts through acoustic environments without amplification. The fully metal body adds sustain and a bright, singing quality to slide notes that wood-bodied guitars cannot replicate. The National Style O was the instrument of the original Delta blues players — Robert Johnson, Son House, Tampa Red — and Spencer’s use of it for acoustic slide work was an act of genuine historical reconnection rather than mere affectation.

Wood-body Dobro resonator instruments — specifically the Model 27 with its spruce top, mahogany back and sides, and spider-bridge resonator system (the Dobro’s characteristic design, using a spun-aluminum cone with a cast aluminum “spider” bridge that contacts the cone at eight points rather than the National’s single biscuit contact point) — also appeared in Spencer’s acoustic slide setup. The spider-bridge resonator system produces a warmer, more acoustic-sounding tone than the National’s biscuit-bridge system — less metallic attack, more fundamental warmth, with a characteristic woody resonance from the wood body. The Model 27’s tone is the sound of the country blues and pre-war gospel slide tradition, and Spencer used it when that specific tonal quality was appropriate.

Standard dreadnought acoustic flat-tops — likely Martin or Gibson examples from the 1960s — appeared in Spencer’s setup for rhythm playing and songwriting, particularly for the acoustic-influenced passages on the Reprise-era Fleetwood Mac records.

Spencer used metal slides — specifically cylindrical steel or brass tube slides worn on the ring finger of his right hand — for his electric slide playing. The choice of metal slide material significantly affects tone: steel slides produce a brighter, more aggressive slide sound with greater high-frequency content; brass slides are slightly warmer and heavier, producing more sustain. Spencer’s approach favoured a heavier slide for maximum sustain and the physical authority that Elmore James’s playing demanded. For the National resonator work, a glass slide (or heavy brass) was used, consistent with the Delta blues tradition in which bottle necks were the original slide material.

Spencer worked primarily in open A (E-A-E-A-C#-E, low to high) and open E (E-B-E-G#-B-E) tunings for slide playing — the same tunings favoured by Elmore James and the broader Delta blues tradition. Open A is one semitone lower in tension than open E (which uses the same chord shape but a step higher), giving slightly different string tension characteristics that affect the slide tone. He also used open G (D-G-D-G-B-D) for specific material. Standard tuning on the Strat and Tele for non-slide work.

For slide playing, Spencer used medium-to-heavy gauge strings — likely .012–.056 or .013–.056 — to provide the string tension and mass needed for clean slide intonation and to prevent the slide from pushing the strings too easily off the fretboard. Heavy strings on a high-action setup are essential for authentic Delta-style slide tone: the added mass produces more fundamental, more sustain, and better note separation between strings. For standard tuning on the Strat and Tele, lighter gauges (.010–.046 or .011–.049) were used.

The Marshall 1962 — known universally as the “Bluesbreaker” combo after its association with John Mayall’s Bluesbreakers and Eric Clapton’s Beano album — was Spencer’s primary amplification for his ES-125 slide work. The 1962 combo specification: JTM45 circuit (based on the Fender Bassman 5F6-A topology with British modifications), KT66 or EL34 output tubes producing approximately 35–40 watts RMS, a GZ34 rectifier tube providing a slightly saggy, compressed feel compared to solid-state rectification, two 12-inch Celestion speakers (either the original T652 alnico-magnet model or the later ceramic Celestion G12-20, depending on production year). The JTM45 circuit’s tonal character — long-tailed pair phase inverter, cathode-follower tone stack, the characteristic warmth and natural compression of KT66 tubes — was perfectly matched to Spencer’s ES-125 and P-90 combination. The hollow-body ES-125’s acoustic resonance interacting with the JTM45’s warm, harmonically complex overdrive at high input levels produced a tone of extraordinary richness and three-dimensional quality — the specific sound of Delta blues amplified through the finest British valve technology of the 1960s.

For larger live performance contexts where the 1962 combo’s 35–40 watts were insufficient, Spencer used the Marshall 1959 Super Lead 100-watt Plexi head — four EL34 output tubes, three ECC83 preamp tubes, long-tailed pair phase inverter, Perspex front panel on pre-1969 examples — into Marshall 4×12 cabinets with Celestion G12M Greenback 25-watt speakers. The 100-watt Plexi’s higher output stage voltage (approximately 480V on the output tube plates compared to the JTM45’s approximately 410V) gives a different compression and saturation characteristic: harder, more aggressive, with a more immediate attack transient than the JTM45’s softer, more rounded feel. For Spencer’s most aggressive, feedback-driven slide work, the Plexi’s higher output and less compressed character gave the slides additional cutting power and sustain.

The original tweed Fender Bassman — four Jensen P10R 10-inch speakers, 4x6L6 output tubes at approximately 45–50 watts, cathode-biased output stage producing its characteristic touch sensitivity and natural compression — appeared in Spencer’s studio setup. The Bassman’s American tonal character — bright, open, less compressed than the British JTM45 at comparable volume settings — gave the ES-125’s P-90 pickup a different flavour for specific studio requirements, pushing the hollow-body’s acoustic warmth into a slightly brighter, more present register. The 5F6-A circuit’s touch sensitivity made it ideal for the dynamic variation between quiet verse passages and full-volume chorus attacks that characterises Delta blues arrangement.

The JMI-era Vox AC30 Top Boost — 30 watts from four EL84 output tubes in fixed-bias push-pull configuration, Top Boost channel with independent treble and bass controls, two Celestion Blue (T530) alnico 12-inch speakers at 15 watts each — provided Spencer with a cleaner, more chimey alternative for specific textural requirements. The AC30’s EL84 output tubes, combined with the Celestion Blue’s alnico magnet and its characteristic “chime” quality in the upper midrange, produced a sound with more top-end complexity and less low-end weight than the Marshall alternatives — useful for the lighter, more rock’n’roll-influenced passages in Spencer’s playing and for the 1950s rock pastiche material that characterised much of Kiln House.

British-made Selmer amplifiers — specifically the Truvoice Stadium, a 15–17 watt combo using EL84 output tubes with a single 12-inch speaker — appeared in Spencer’s early setup before the Marshall Bluesbreaker became his primary tool. The Selmer Truvoice was a budget-range British amplifier of considerable character: its EL84 output section produces a characteristic compression and harmonic saturation at relatively low volumes, and its simple tone controls (treble and bass only) give a direct, unprocessed relationship between input and output that suits blues playing well. Many early British blues players used Selmer amplifiers before the Marshall became universally dominant, and the Selmer’s tone has a raw, primitive quality that actually complements pre-war and early electric blues material quite effectively.

The original Dallas Arbiter Fuzz Face — chrome enclosure, NKT275 PNP germanium transistors, two-transistor series feedback topology with a 470 ohm emitter resistor on Q1, a 33k base bias resistor on Q2, and a 100µF output capacitor — was present in Spencer’s signal chain for specific applications. His use of the Fuzz Face with the ES-125 hollow-body was notably different from its application on solid-body instruments: the hollow body’s acoustic resonance and the P-90’s broader, more complex frequency response interacted with the Fuzz Face’s clipping character to produce a more complex, less saturated fuzz tone than the same pedal through a Les Paul, with more of the guitar’s natural character preserved within the fuzz texture. The NKT275’s characteristic warm, cleaning-up-with-volume response meant Spencer could use the guitar’s volume pot to dial between fuzz and clean while the pedal remained engaged — a crucial operational characteristic for a player working in a dynamic blues context.

The Dallas Electronics Rangemaster Treble Booster — OC44 PNP germanium transistor, common-emitter configuration, 68k base bias resistor, 470µF bypass capacitor producing the characteristic high-pass filter at approximately 2.3kHz, input impedance approximately 470k ohms — appeared in Spencer’s signal chain ahead of the Marshall amplifiers. The Rangemaster’s frequency-selective boost — it primarily pushes the upper midrange and treble rather than providing a full-range boost — compensated for the ES-125’s naturally warm, mid-forward character by adding upper-frequency energy that would otherwise be masked by the hollow body’s acoustic warmth. Through the JTM45 circuit, the Rangemaster + ES-125 combination produced the harmonically saturated, cutting slide tone that is audible on the early Fleetwood Mac recordings.

The Vox V846 wah — Fasel hand-wound inductor, 100k audio taper pot, BC109C silicon transistor (1967-onward production), sweep from approximately 450Hz (heel down) to 1.6kHz (toe down) — appeared selectively in Spencer’s live setup. His wah use was relatively sparse — the raw, unprocessed character of his Delta slide approach didn’t require the vocal filter character that the wah provides — but for specific passages requiring that expressive frequency modulation, the V846’s warm Fasel-inductor sweep gave the most musical result. The Fasel inductor’s handwound construction meant individual units had slightly different resonant peak characteristics, giving each pedal a unique tonal character — original Fasel-equipped wahs are considerably more sought-after than later Halo-inductor replacements.

The Sola Sound Coloursound Tonebender MkIII — distinct from the earlier germanium MkI and MkII models, using silicon BC108C transistors rather than OC75 or OC81D germanium devices — appeared in Spencer’s later Fleetwood Mac setup. The silicon Tonebender MkIII’s character is quite different from germanium Tonebender models: silicon transistors produce a brighter, harder, more aggressive fuzz with greater gain and less of the warm “bloom” of germanium. The MkIII uses three BC108C transistors in a modified topology producing a sustained, harmonically complex fuzz with good note separation but more “buzziness” than the warmer germanium alternatives. For Spencer’s most aggressive, full-volume slide work, the silicon Tonebender’s harder edge cut through the mix more effectively than the germanium Fuzz Face’s warmer character.

The DeArmond Model 601 Tremolo Control — one of the earliest production guitar effects pedals, introduced in the mid-1950s and continuously produced through the 1960s, using a motor-driven variable resistor (a spinning disc with conducting and non-conducting sections interrupting the signal path) for amplitude modulation — provided Spencer with a vintage tremolo effect. The motor-driven mechanical tremolo of the DeArmond 601 produces a more irregular, less perfectly metronomic modulation than electronic LFO-based tremolos, giving a slightly “breathing” quality to the effect that complements acoustic and vintage blues material. The 601’s depth and speed controls allow a wide range of tremolo intensities from gentle shimmer to choppy, almost sounding gating. This effect was used by Spencer for atmospheric rhythm passages and for certain lead passages requiring the tremolo’s distinctive pulsing quality.

For live performances featuring the National Style O resonator, Spencer required no electronic amplification — the National’s volume projection was sufficient for club-level performance. For larger venues, a simple microphone (likely a Shure SM57 or similar dynamic microphone, positioned at the resonator cone) into the PA system provided amplification without the tonal alteration that running a resonator through a guitar amplifier would produce.