Zon

Sonus

Joe Zon spent years fixing other people’s bass necks. Then he built one with nothing on it to adjust.

Redwood City, California, January 1992. Joe Zon has a composite neck, a heel sunk deep into a swamp-ash body, and a plan to make the whole thing feel like an old Jazz Bass. The factory calls it a Jazz Bass for the ’90s, and prints the trademark asterisk.

Introduced: 1992
Type: Solidbody bass
Class: Production

Read the story · 3 min

All guitars More Zon

Photo: kallerna / Wikimedia Commons / CC BY-SA 3.0Adam Duce with a metallic Zon Sonus live at Sonisphere 2009, Pori; player-with-guitar fallback.

The short version

1981
Buffalo
May. Zon opens at the Buffalo Guitar Outlet. Joe remembers the first NAMM showing as 1982.
1981
First endorser
October. Rick James, on a Signature and a Standard. Years before the Sonus.
1987
Redwood City
September. The shop moves to California and goes full-time.
1992
The Sonus
January. A bolt-on composite neck, two single-coils, and a Jazz Bass feel.
1993
Five strings
February. The Sonus 5 arrives on the same 34-inch neck.
1994
The Special
January. A six-string, and a Special with the neck pickup moved toward the bridge.
2004
A maple one
The RT5 for Robert Trujillo, who wanted wood for the old songs.
2015
Billy Gould’s BG4
A tulipwood Sonus with a truss rod and a distortion switch. The first 25 are signed.

Side A

The Hofner that fell apart

It starts with a cheap bass. Joe Zon’s parents bought him an imitation Hofner, and it wouldn’t stay together. So in his late teens he drew a body, cut it out of wood a family friend had, and took the cavities out with a chisel.

Then came repairs. First in a basement, then at a bench he rented at the Buffalo Guitar Outlet. The company opened there in May 1981. Joe remembers the first NAMM showing as 1982. The factory timeline says June 1981. Either way, he spent those years as the guy people brought their basses to when something went wrong.

A lot of what went wrong was necks. Wood moves. Necks twist. The Sonus is what a repairman builds when he’s tired of fixing the same problem.

Borrowed shells

The fix Joe wanted was graphite. Modulus already had a composite neck, and the patent on it. So Joe carved the master, and Modulus supplied the shells. He says they made his necks for about five years and wouldn’t license anything. Other accounts have Modulus making parts of Zon necks until the patent ran out in the early 1990s. Those aren’t quite the same story, and nobody has lined them up.

What he’s firm about is now: people still think Modulus builds Zon necks, and they don’t. Different look, different feel, different sound.

By then the shop had moved across the country. In September 1987 Zon set up in Redwood City, California, and went full-time. In January 1992 it introduced the Sonus.

No rod to turn

Zon wouldn’t build a composite neck that runs through the body. A carbon stick all the way through sounds “too sterile” to them, and it keeps the wood from doing its part. So you bolt it on or you glue it in. The Sonus is the bolt. The Legacy is the glue. Joe’s version: bolt-on is punch, set-in is more open. “Period.”

The heel is sunk deep so the neck can’t shift sideways. The neck is carbon fiber plus wood, plus things he doesn’t list. The fingerboard is phenowood: veneers, usually birch, dyed black, bonded with phenolic resin, and pressed from about three inches thick down to a quarter inch. The factory calls it ebony-like.

And there’s no truss rod. Zon’s own guide says composite necks carry “proper playing relief without the aid of a truss rod,” and “do not require any adjustment.” A tiny bit of relief is built in. Joe calls it “the John Entwistle school”: the action as low as it’ll go without too much buzz on a fretted note.

The guy who spent years fixing necks built one without a truss rod.

Flip the record · By the numbers

0
Truss rods in the composite Sonus neck. The relief is built in.
~5
Years Modulus made Zon’s neck shells from Joe’s master, by his count.
3″ → ¼″
Birch veneers and phenolic resin, pressed down to make the fingerboard.
24
Frets on a 34-inch neck. Two full octaves.

Side B

A Jazz Bass for the ’90s

Pick one up and it’s meant to feel familiar. The neck is two octaves, 24 frets on a 34-inch scale, “tapered and shaped to feel like a vintage Jazz Bass neck.” The two single-coils are Bartolini, wound for this bass and not pulled from a drawer, “to reproduce the classic Jazz sound.” So listen for a Jazz: two singles, blended. What’s different is behind the knobs.

The preamp is active. Polyfusion, where Joe learned active circuits, builds it: master volume, a blend between the pickups, stacked bass and treble, and a mid control inside the cavity. The body is two-piece swamp ash, finished flat satin. Gloss costs extra, because it takes more work. The satin looks like oil, and it isn’t.

Then it grew. A five-string in February 1993. In January 1994 came a six, and the Sonus Special: keyboards had been burying the bass, so Joe moved the neck pickup toward the bridge, paired bubinga with ash, and switched to Bartolini multi-coils.

The one who wanted wood

Robert Trujillo liked the Sonus body. He’d played the composite necks, and he wanted wood “for the old stuff.” It took about a year of back-and-forth and, by Joe’s count, “a couple thousand miles” on the truck. The RT5 that came out of it has a solid maple body and a maple neck. Don’t pin a Metallica record on a stock Sonus 4.

Billy Gould’s BG4, from 2015, stayed composite and picked up the thing the guide said you didn’t need: a truss rod. It also has tulipwood, controls on the back, and a distortion switch. Adam Duce of Machine Head turns up in one caption playing a Sonus, and in another interview says he wanted “the most simple, non-moving parts bridge” on his Zon. Nobody has said those are the same bass. Michael Manring is the player most tied to the brand, but his instrument is the Hyperbass, a different bass entirely.

Joe is still the builder. The Sonus 4 is still on the factory’s list: satin ash, 34 inches, a graphite nut, and a neck with no rod in it. The kid whose cheap bass fell apart built one that leaves the next repairman nothing to turn.

The cast

The people, and the specific guitars, that made the legend.

1981
Joe Zon
Builder
Started out repairing instruments in Buffalo. Still the builder in Redwood City.
2015
Billy Gould
Sonus BG4
Faith No More. Tulipwood, a truss rod, bass and treble on the back cover, and a distortion switch on the front.
2004
Robert Trujillo
Sonus RT5, maple
Liked the Sonus body but wanted a wood neck “for the old stuff.” That bass is maple, not composite. Don’t pin Metallica on a Sonus 4.
Adam Duce
A Sonus, in one caption
Machine Head. Photographed with “a Sonus model.” Separately, he said he wanted “the most simple, non-moving parts bridge.”
1992
Michael Manring
Hyperbass
The player most tied to Zon, on a different instrument. The Hyperbass went into production two months after the Sonus.
1981
Rick James
Signature and Standard
Zon’s first endorser, eleven years before there was a Sonus.

Liner notes

Specs, construction, rarity, value, and every source we used.

Two Bartolini singles on swamp ash, and a bolt-on composite neck — Zon’s Sonus, not the set-neck Legacy and not Trujillo’s maple.

Body: Two-piece select swamp ash. Natural. Flat satin; gloss is extra. Blue Book: offset double-cutaway. The series page still says high-gloss polyester. Do not average the finishes.
Neck: Composite, bolt-on, flat urethane, deep inset heel. User’s guide: relief is built in; no truss-rod adjustment. The BG4 card lists a dual-action rod. Not this row.
Fingerboard: Phenowood, side dots only, 12" radius, 24 medium frets. FAQ: usually birch, phenolic resin. Necks page also names maple in the sandwich.
Scale: 34". No millimetres. The Sonus 5 page is also 34".
Pickups: Two Bartolini, custom-wound. Narrow-aperture passive linear single-coils, JB shells, neck and bridge.
Hardware: Zon machined brass bridge. Spacing printed .750"/19mm — mix flagged; center-to-center is not stated. Gotoh GB-7, chrome. Hipshot Xtender is an option.
Electronics: ZP-4 by Polyfusion. Master volume, pickup blend, stacked bass/treble, internal mid. Page prints boost/cut +/15dB. One 9-volt, 300 hours on this card. The guide’s ZP-4 card for the 4/2 and 5/2 says 200 hours. Do not average.
Finish: Flat satin body, natural; flat urethane neck. Gloss, transparent, and solid colors are options.
Nut: Graphite, 1.532". No millimetres. Width at the 24th fret on this card: 2.437".

Open the full research fileConstruction details, the complete player record, production numbers, dated value estimates, and sources

Current factory card = Sonus 4 (Redwood City), fetched 24 September 2026. No price on the page. Sonus 5 (February 1993): same 34" composite neck, nut 1.875", 2.875" at the 24th, spacing .687"/17mm — another mixed pair, not this row. Special, 4/1, BG4, Classic, RT, RTK, maple-neck Sonus Standard, and Lightwave are other cards. Legacy is the set-neck. Hyperbass is Manring’s tuner bass. A Reverb title prints 35" on a Sonus 5/2. Not this card. Do not convert. Do not average 34 and 35.

Construction

The job was a bass that felt like a Jazz and did not come home with a twisted neck. Joe Zon had been the person fixing those necks.

An imitation Hofner his parents bought would not stay together. That is why he started building, in his late teens: a body drawn and cut from wood a family friend had, cavities taken out with a chisel (Cliff Engel, June 2005). Repairs followed: a basement, then a bench he rented at the Buffalo Guitar Outlet. The factory timeline opens the company there in May 1981 and unveils Signature and Standard basses at the Chicago NAMM in June 1981. In the 2005 interview he puts that debut in 1982. A shop tour page has him repairing from 1978 and starting the company four years later. Keep 1981 and 1982. Those first basses are not this one. Rick James, October 1981, is the first endorser, on Signature and Standard. John Wetton, Joe says, was a Legacy man. Pre-Sonus.

The neck was the point. College graphite, then Modulus, who already had a composite neck and the patent. Joe carved the master. Modulus supplied the shells. He says they made his necks for about five years and would not license anything. Wikipedia has Modulus making elements of Zon necks until the patent ran out in the early 1990s. “About five years,” with no start date, is not the same claim as a patent running into the early 1990s. Keep both. He also says people still think Modulus builds Zon necks, and they do not: different look, feel, and sound. The Sonus is January 1992 — the timeline’s spelling is “Janurary.” Do not give that first Sonus a Modulus shell nobody pins. By then the shop had moved. September 1987, Redwood City, full-time building. November 1995 is a larger room in the same city, not a second city.

What he would not build was a composite neck-through. Necks page and FAQ: a carbon stick through the body sounds sterile, and it keeps the wood from speaking the way they want. Bolt the neck on, or glue a dovetail. Sonus is the bolt. Legacy is the glue. Joe, 2005: bolt-on is punch, set-in is more open. “Period.” The heel is sunk so the neck cannot shift sideways. The recipe is carbon fiber plus wood, plus things he does not list, made in Redwood City. The board is phenowood, not graphite. Veneers, usually birch, dyed black, phenolic resin, pressed from about 3" down to 1/4" (necks page). The FAQ calls it ebony-like. The printable user’s guide: composite necks “do not require any adjustment” and carry “proper playing relief without the aid of a truss rod.” Wood necks on other Zons do. In 2005 he still says you will not be adjusting a rod, and that a very small relief is built in — “the John Entwistle school,” action as low as it will go without too much buzz on a fretted note.

Ash, satin, gloss if you pay. Joe splits flat urethane from high-gloss: more labor in the gloss, and the flat looks like oil and is not. The series overview still says high-gloss polyester and “independent pickup volumes.” The card says blend, an internal mid, and 300 hours. Do not average them. The line they kept is the job: a two-octave bolt-on “tapered and shaped to feel like a vintage Jazz Bass neck,” singles “wound to reproduce the classic Jazz sound.” Their name for January 1992 is a Jazz Bass for the ’90s. Fender’s mark. They print the asterisk. Bartolini winds the coils for the bass, not from a drawer. Polyfusion, where he learned active circuits, builds the ZP-4. Blue Book says two-per-side tuners, calls the board phenolic, and runs the model 1992–present. Phenolic is their word for phenowood. Not a second board.

Then it forked. February 1993, the five-string. January 1994, the six-string and the Sonus Special: keyboards had buried the bass, so he moved the neck pickup toward the bridge, paired bubinga with ash, and used Bartolini multi-coils. No measurement of that move. January 1996, the 5/1. January 1997, the 4/1. A Lightwave Sonus, infrared plus piezo, sits in the user’s guide. Not the ZP-4.

The wood neck is the split. He says he resisted maple until Trujillo, who had played the composites and wanted wood “for the old stuff.” A year of trips, “a couple thousand miles” on the truck. The RT5 keeps the outline and leaves the table: only solid-maple body they offered then, a different profile, the only EMGs as of that interview. Guitar World, 30 January 2007, has the same reason, and calls that Korean board South American pau ferro. The RTK page prints rosewood, a dual-action rod, and retail $1,830. Do not average the two board names. The BG4 stays composite and grows the rod the guide said you did not need: tulipwood, Zichri’s distortion, street $3,599, first 25 signed. A signature. The maple Sonus Standard borrowed the name too. The ash card and the builder link were still up on 24 September 2026. They still do not print a price.

Players

The Hyperbass, the Legacy, the VB, and Trujillo’s maple RT are other basses. So is a Wikipedia line that only says “a Zon.”

Billy Gould. The Sonus the factory will specify. Faith No More. Tulipwood, the rod, bass and treble on the back cover, volume and the distortion switch on the face, a wide dual-coil at the neck and a narrow single at the bridge. NAMM 2015. Same 34" and 1.532" nut as the ash four. His bass. Not that table.

Robert Trujillo. The trap. After Ozzy, into Metallica, introduced by Craig McFarland. He liked the Sonus body. He did not want the composite neck for the old songs. The interview’s intro dates the RT5 to 2004. Guitar World: U.S. list $2,595; the Korean RT5K “saving you a cool $900”; close to a year “dialing it in,” because he wanted wood “for vintage Metallica material.” Do not hang a Metallica record on a phenowood Sonus 4. Do not call the RT graphite because the brand is.

Adam Duce. Wikipedia’s Zon page captions him, with Machine Head, “playing a Sonus model.” Guitar World’s later vault piece says the last time they spoke he was on a Zon, and quotes him: he sweats, so he wanted “the most simple, non-moving parts bridge,” and he put bass and treble on the back, set with a screwdriver. That piece does not print Sonus, a scale, or a serial. The caption and the quote are not one bass until a source says so. No Machine Head track is pinned here.

Michael Manring. The name on the brand, and the wrong instrument. Timeline: Hyperbass born October 1990, production model March 1992, two months after this bass. Four detuners, altered tunings. Not a Jazz-shaped bolt-on. Wikipedia, from his FAQ: a custom Sonus/Hyperbass hybrid, plus a VB4 and Legacy Elites. The hybrid is one object. It is not this card. The January 1992 NAMM night was for Drastic Measures. Same month. Not this bass.

Wikipedia’s user list also names Mark King. Nothing here puts a Sonus in his hands. His graphite is the Status plate (status-series-ii). Arion Salazar’s El Toro uses Sonus electronics, a composite neck, and LEDs in the dots. The factory page calls it a one-off, not a Sonus.

Also known to play stops there. A Zon on a list is not this model.

Rarity

Blue Book still runs the Sonus 4 from 1992, and the spec sheet is still up. That is not a count. Zon has not published a Sonus total. None invented. The five years of Modulus shells are the early shop. They do not number 1992 necks. A serial dates one bass. BassBros’ natural, serial 937141, is a fretless someone fretted later. One object. Not a year.

What is thinner: a 1992, before the five-string in February 1993; a Special from the January 1994 NAMM, pickup moved, multi-coils; one of the first 25 signed BG4s. Twenty-five is that slice. Not the line.

The maple RT, the Korean RTK, and the maple Sonus Standard wear the name. They are easier to mistake for this bass than they are to stand in for it.

Value

Informal estimate, 24 September 2026. Not an appraisal.

Ask versus sold, labeled. Celebrity instruments are not comps. No invented medians. No clean Reverb Price Guide band for a stock Sonus 4. Flag: thin sold-comp access.

New street. The Sonus 4 card prints no price (24 September 2026). None invented off the builder link. Other cards, not this ash composite: BG4 street $3,599 with gig bag. Guitar World, 30 January 2007: U.S. RT5 list $2,595, the Korean a $900 savings, and instruments from the company “in the $4,000–$7,000 range.” RTK page: retail $1,830. Wood necks, or a signature with a rod. Not a 2026 Sonus 4.

Used. Named asks, not hammers, this pass. Reverb’s Zon 4-string page: a 1993 gloss Sonus, Excellent, $3,995 (from $4,500). A Sonus Custom 5, Excellent, composite, phenowood, 34", $3,679.50 (from $4,027.55), item 88858179. Do not average a 1993 four-string with a Custom 5. Ended ask, not a hammer: Gold Rush Sonus 4, $1,899, listed nine years ago (item 6117946). BassBros’ natural, serial 937141, $2,786.84, ended about a year ago (item 89835052): converted fretless, 22 frets on the listing, 8 lbs/3.7 kg. Not stock. Not a comp.

Vintage / collectible. No closed vintage SKU. A 1992 and the current card are the same model. No separate auction series. Gould’s bass and Trujillo’s RT have no hammer here. Not comps. Leave these out of any average: G-Brat’s 1996 Sonus 5 at $3,699 is a five-string ask; a Basschat 4/2 custom marked sold at €3,000 plus shipping (April 2025) is alder, with a truss rod.

Sources

Zon Guitars, History — May 1981, Buffalo Guitar Outlet; June 1981 NAMM Signature and Standard (Joe later says 1982); Rick James October 1981; September 1987 Redwood City; January 1992 Sonus, “Jazz Bass of the ’90s,” and the Manring NAMM for Drastic Measures; March 1992 Hyperbass production; February 1993 five-string; January 1994 six-string and Special; November 1995 larger Redwood City shop; January 1996 Sonus 5/1; May 1996 Sonus VIII; January 1997 Sonus 4/1
Zon Guitars, Tour — repairing from 1978; company “four years later”; Sonus, Sonus V, and Sonus VI as bolt-on composite necks on satin two-piece ash. The 1978 line does not match the May 1981 founding. Keep both
Zon Guitars, Sonus series — Jazz-neck line; select ash; linear singles; independent volumes; natural high-gloss polyester. Do not average with the Sonus 4 card
Zon Guitars, Sonus 4 — living card: two-piece swamp ash; flat satin; composite bolt-on; 34"; phenowood; 12"; graphite nut 1.532"; 24 medium; 2.437" at the 24th; ZP-4; +/15dB; one 9-volt; 300 hours; Bartolini linear singles; brass bridge .750"/19mm; Gotoh GB-7. No price
Zon Guitars, Sonus 5 — 34"; nut 1.875"; 2.875" at the 24th; spacing .687"/17mm
Zon Guitars, Necks — deep inset bolt-on versus set-in Legacy; no neck-through; carbon fiber plus wood, Redwood City; phenowood from about 3" to 1/4", maple or birch; graphite nuts
Zon Guitars, FAQ — phenowood usually birch; Bartolini windings are not off-the-shelf; neck-through “too sterile”
Zon, printable user’s guide (PDF) — composite necks: relief without a truss rod; wood necks need one; ZP-4 on Sonus 4/2 and 5/2, 200 hours. Not the Sonus 4 card’s 300 hours. Lightwave Sonus is a separate card in the same guide
Zon Guitars, Sonus BG4 — Gould; tulipwood; composite bolt-on with dual-action truss rod; 34"; nut 1.532"; 19mm string-to-string; rear bass/treble; Zichri distortion; street $3,599 with gig bag; first 25 signed; NAMM 2015
Zon Guitars, Sonus RTK5 — Korea; maple neck, rosewood, dual-action rod; retail $1,830. Not this neck
Zon bass builder, Sonus Standard — maple body, three-piece maple neck, rosewood board, Duncan dual-coils. Prices on that page were dated 1 January 2018 and the dollar cells did not load. Not this composite card
Cliff Engel, Joe Zon, June 2005 — Modulus shells about five years, from his master; current necks are not Modulus; Sonus Special; bolt-on versus set-in; Entwistle-school relief; Trujillo, wood neck for the old songs, RT5 the only solid maple and the only EMGs then; 1982 NAMM in his telling; Redwood City 1987; Wetton on the Legacy
Guitar World, Ed Friedland, 30 January 2007 — U.S. RT5 list $2,595; Korean saves $900; maple neck and pau ferro on the review bass; wood neck for vintage Metallica; company instruments in the $4,000–$7,000 range. The factory RTK card says rosewood, not pau ferro
Guitar World, Adam Duce vault piece — “a Zon”; simple bridge; bass and treble on the back. Does not print Sonus
Wikipedia, Zon Guitars — Modulus until the early-1990s patent lapse; Duce captioned on a Sonus; Manring’s Sonus/Hyperbass hybrid. The user list is the brand
Blue Book of Guitar Values, Zon Sonus 4 — offset double-cutaway; two-per-side; phenolic in their wording; mfg. 1992–present. Dollar widget not used
Reverb, Zon 4-string — 1993 gloss Sonus ask $3,995 from $4,500, this pass. Not a hammer
Reverb, Sonus Custom 5, item 88858179 — ask $3,679.50; composite; phenowood; 34"; nut 1.875"
Reverb, Sonus 4, item 6117946 — ended ask $1,899, listed nine years ago
Reverb, Sonus 4 natural, item 89835052 — ended ask $2,786.84; serial 937141; converted fretless; 22 frets; 8 lbs/3.7 kg. Not a stock comp
Fretboard Journal, Joe Zon, February 2024 — still the builder; composite necks, bolt-on versus neck-through, Hyperbass as its own problem. No Sonus price
Zon, El Toro — Salazar one-off; Sonus electronics; composite neck; LEDs in the dots. Not a Sonus
G-Brat’s Guitars, 1996 Sonus 5 — dealer ask $3,699; graphite neck; 34"; 8 lb. A five-string, not a hammer
Basschat, Sonus 4/2 Custom 2009 — marked sold, €3,000 plus shipping, April 2025; alder; truss rod. Not the ash card