As with all things guitar, a little patience can yield big dividends.
Think about the last time you bought a new pair of shoes. When trying them on in the store, you probably thought, “These feel pretty good, but I bet they’ll feel amazing once I get them broken in.” So you bought the shoes and wore them every chance you could. Eventually they folded and creased in all the right spots to conform to the shape of your foot.
Now think about the last time you bought a new speaker. Maybe you tried it out, but didn’t immediately like it. Or perhaps you’ve never bought a new speaker and are hesitant to do so because you’re not sure what to expect. All right, what’s the connection between speakers and shoes? The answer is simple: Just like footwear, new speakers need to be broken in. If you didn’t know that, you’re not alone. Many guitarists don’t realize that new speakers need time to break in before they reach their ultimate tonal potential.
Before we can understand why this is necessary, we must understand what needs to be broken in. There are two main parts to consider: the cone and the spider. You probably know what the cone is, but may not be familiar with the term spider. The cone connects to the front of the voice coil. The spider is the term for the suspension that attaches the rear of the coil to the frame. (To see an exploded diagram of a speaker, check out “Alnico or Ceramic … What Gives?”)
For a speaker to function, the voice coil, cone, and spider must all move in and out as one piece. The electric signal from your amplifier causes the voice coil to move back and forth, creating an electromagnetic motor. The spider holds the voice coil in place, and the cone projects the sound outward.
The cone is traditionally made of paper, while the spider is usually a mesh-like material that has been formed into a specific shape. When brand new, these two components are very stiff, and this affects the speaker’s sound right out of the box. This stiffness can create a bit more high-end fizz and somewhat strangled lows, or very little highs and unfocused lows.
The part of the cone where the most movement takes place is the outer edge, or surround. This is the primary focus of speaker break-in, as this is where the most physical change will occur. It’s not a change you can readily see, but relates to microscopic breaks in the paper fibers. This occurs to a lesser extent in the spider, but the main emphasis is on the surround.
So how do you break in a speaker? Players and techs use many methods, though it all amounts to the same thing—getting the cone to move, which causes those creases and breaks to happen. This process necessarily takes time, our most precious commodity, which explains why some folks run recorded music through a speaker, while others use a Variac to send a 60-cycle hum into it. Some folks chemically “age” their cone with fabric softener (though that seems like cheating to me).
Personally, I don’t care for any of these methods. I like the good old-fashioned approach—simply playing guitar. It makes sense to feed a speaker the same frequencies it will receive in the future, and the variability in your playing won’t cause the same heat buildup as a Variac. The break-in period depends on the speaker and how it’s designed. To get a speaker mostly broken in, I recommend playing through it at a moderate volume for 12 to 20 hours—but it could even take 50. As the creases work into the cone, the unwanted fizz or strangled sound will diminish or disappear, and the speaker gets a little louder.
Sure, a speaker might not sound exactly like you want at first, but it will only get better and better the more you play it—just like those new shoes once you wear them for a while. Best of all, this “play it in” approach gives you a reason to practice—something I always encourage.
When Louis Cato received this Univox LP-style as a gift in high school, it needed some major TLC. A few years later, it got some practical upgrades and now makes regular appearances with Cato on The Late Show.
The self-described “utility knife” played drums with John Scofield and Marcus Miller and spent time in the studio with Q-Tip before landing on Stephen Colbert’s show as a multi-instrumentalist member of the house band. Now, he’s taken over as the show’s guitar-wielding bandleader and is making his mark.
It’s a classic old-school-show-biz move: Bring out the band, introduce them one by one, and build up the song to its explosive beginning. It’s fun, dramatic, audiences love it, and that’s how every The Late Show with Stephen Colbert taping starts.
By this time, us audience members have been sitting in Manhattan’s chilly Ed Sullivan Theater for about 90 minutes. We’ve gotten our seats, had a bathroom break after getting settled, and had some fun with warm-up comic Paul Mecurio. The first musician summoned by announcer Jen Spyra is drummer Joe Saylor. Wearing his trademark cowboy hat, he jogs out, gets behind the kit, and kicks off an up-tempo second-line groove. Next comes upright bassist Endea Owens and percussionist Nêgah Santos. The band’s trumpeter, Jon Lampley, is introduced, and he’s brought along his bandmates in the Huntertones as guests, so saxophonist Dan White and trombonist Chris Ott come out as well.
Louis Cato feat. Stay Human "Look Within"
The multitalented Louis Cato leads the Stay Human band through a special rooftop performance of his song “Look Within,” from his album, Starting Now.
The audience is now on its feet, the band’s pocket is thick, and the energy is building. When bandleader Louis Cato charges onstage, he reaches his mic on the bandstand and shouts, “I feel good today!” with explosive enthusiasm and a big grin, and the band launches into Jon Batiste’s “I’m from Kenner.” Cato sings the catchy and gleeful refrain: “I feel good, I feel free, I feel fine just being me / I feel good today.” And the audience is feeling the love. Almost everyone is bouncing and clapping along.
A couple minutes in, when it seems like the song has reached its super-positive-vibe, high-energy climax, Cato shouts into his mic, “How do you feel today, Stephen?” And with that, Colbert comes running out from the middle of the set. Cato leaps from the bandstand toward the host as the crowd explodes. The two grab hold of each other and attempt to spin around, but the bandleader, holding his black-sparkle Tuttle T-style, loses his grip and goes sliding across the shiny stage. There’s a second where both are comically stunned—Kevin McCallister Home Alone-expressions on both of their faces—but Cato quickly jumps to his feet, both he and his guitar unharmed, and runs back to the bandstand, where he keeps the song moving along with his bandmates, who haven’t missed a beat.
All this excitement isn’t even for the TV audience! Colbert is coming out for the un-televised pre-show Q&A. In a few minutes, they’ll do a new taped intro that looks more like what we see every night. But they’ve gotten the crowd energized, and we need to keep it up. They need our energy to do their jobs.
The Late Show Band welcomes a lot of guests up on the bandstand. Here, Cato and Joe Walsh boogie down.
Photo by Scott Kowalchyk
As Cato sees it, that’s what his role as bandleader is all about: keeping the audience engaged and amplifying the drama and action of the show. “That translates to the energy that the viewers get at home,” he explains. “For all of us here, we’re able to feed off that energy and do the best possible show that we all can.”
Colbert agrees with that job description and adds that the bandleader himself has the same contagious effect on his players. “Louis is an extraordinarily gifted multi-instrumentalist,” he says, “whose spirit of creativity and collaboration not only elevates everything the band does musically but inspires me to be better at my job.” He adds, “I’m so happy to call him my friend.”
Beyond his infectious energy and charisma, there are a lot of ways Cato keeps the Late Show Band invigorated from night to night. For one, he keeps the music fresh by tackling a new cover song every day. That doesn’t mean running down rote note-for-note charts. Cato and the band take a reconstructionist approach that fans of his work—whether from his collaborations with artists such as the Huntertones, Scary Pockets, or Vulfpeck, or from his regular Instagram cover-song posts—will recognize.
“Louis is an extraordinarily gifted multi-instrumentalist whose spirit of creativity and collaboration not only elevates everything the band does musically but inspires me to be better at my job.”—Stephen Colbert
On this evening, the band runs through a host of multi-genre reinterpretations during the two-episode taping, including a slow-burning and soulful “Smokestack Lightning,” a New Orleans-style “Down by the Riverside,” and a fingerpicked, acoustic-led take of Joni Mitchell’s “Free Man in Paris” that gets Colbert lip syncing along off camera. On a horn-driven arrangement of Stevie Wonder’s “Love’s in Need of Love Today,” there’s a re-worked bridge that creates a generous feature spot for the guest horn players.
Every arrangement brings a new and unique perspective to a classic track, to ensure the band is “not just a wedding band doing a cover of a song on the radio.” Cato adds, “We’re arranging it and making it our own—because that’s the sonic fingerprint of our show.”
St. Vincent jams with Louis and crew.
Photo by Scott Kowalchyk
A Lifelong Path
Listening to the story of Cato’s musical life, it seems that this job—with its demand for a blend of careful strategizing and on-the-fly creative thinking, as well as effortless instrumental skills and charismatic showmanship—is what he’s been training for since the beginning.
On the morning of the taping I attended, I meet Cato in his dressing room. Painted with sky-blue walls and a cloud mural on the ceiling, it’s a comfortable place to hang. The bandleader is wearing slim-fit floral pants, a hoodie over a black T-shirt, and a long necklace. He sits across from me on his couch, next to a guitar stand that holds a few instruments—including his Tuttle, a Jesse Stern-built baritone acoustic, and his Univox LP-style—and a ’65 Deluxe Reverb reissue with a Universal Audio Dream ’65 pedal plugged into it.
“There’s not a time in my brain when I was not making music in some way or form,” Cato says. His mother, a pianist in the Church of God in Christ, bought her son a Diamond drum kit that he recalls having paper heads when he was just 2 years old, and she started teaching the toddler to accompany her. “I marvel at my mom,” he laughs. “Like, who buys their 2-year-old a drum kit?” After playing those drums every day for a year, he started accompanying her at services.
The family moved around a lot. Cato’s father was in the Air Force, and Louis was born on a base in Lisbon, Portugal, before moving to Dayton, Ohio. Not long after he started playing in church there, they moved again to Washington, D.C., and when Louis was 5 they settled in Albemarle, North Carolina. A few years later, Louis started playing guitar on a “little burgundy sunburst acoustic. Eventually, I busted a string and busted another string and just kept playing with four strings. I delved more into bass from playing bass lines on the acoustic guitar. So, for my 9th birthday, my dad bought me a 4-string bass.”
“I’d show up to Tip’s and we’d do a week of writing sessions with John Legend or have André 3000 in the studio for a couple of weeks.”
While it was strictly pragmatic reasons that initially drew him to the bass, he says his biggest inspiration was the bass player he knew best: his mother’s left hand. Her playing, rooted in the COGIC (Church of God in Christ) style, “involves heavy left-hand bass. I wasn’t as psyched to play bass in church since the way my mom plays is very defined. But eventually I kind of had to learn how she plays. It was always just her and me playing. And I had to learn to move with that and follow that. She’s a great bass player.”
Along the way, Cato picked up more instruments. By the time he headed to Berklee, he was playing drums, guitar, and bass as well as tuba, trombone, and euphonium. “I was going from being a big fish in a small pond to a small fish in a large pond of super-talented people who had heard oodles of music I had never dreamed of,” he recalls. So, he decided to focus his studies on the instrument he’d played the longest.
Louis Cato's Gear
A glimpse at Cato’s pedals and amp, which mostly live outside of the camera’s eye, behind his stage monitor.
Guitars
- Univox LP-style
- Tuttle Custom Hollow T
- 1961 Gibson SG reissue
- Martin OM-28
Amps
- ’65 Fender Princeton Reverb reissue
Effects
- Boss FV-500H Volume Pedal
- Boss TU-3 Chromatic Tuner
- Dunlop Cry Baby
- 3 Leaf Audio Octabvre
- J. Rockett Archer
- Truetone Jekyll & Hyde
- Xotic RC Booster
- MXR Carbon Copy
Strings and Picks
- D’Addario EJ16 (.012-.053)
- D’Addario EXL110 (.010-.046)
- Dunlop Max Grip .88 mm
Cato completed just two semesters—fall ’03 and spring ’04—before deciding to concentrate on playing the gigs that were paying his bills. “My rationale was, much to my parents’ chagrin, here’s an opportunity where I can keep learning on the job and be working my way out of the debt I went into in this year.”
Gigging with wedding and church bands gave the multi-instrumentalist an opportunity to keep all his instrumental and vocal skills alive. “My oldest daughter was born soon after that,” he recalls, “so I felt really, really aware of how lucky I was, how lucky any of us are, to make a living and support a family as a musician.” Cato spent five years in Boston, playing various instruments in gigging bands, and he frequented local institution Wally’s Cafe Jazz Club, just two blocks down the street from Berklee, “for self-education and inspiration. When that felt like I hit a ceiling, I looked at where I could go to continue my inspiration and working on the kind of projects I wanted to be working on, and that led me here.”
By that time, Cato’s friend Meghan Stabile, had moved to New York and created the promotion and production company Revive Music, which was dedicated to the kinds of jazz and hip-hop collaborations he wanted to pursue. Cato moved to Bushwick, Brooklyn, with his band Six Figures— “There were six of us; we did not make six figures!”—and would head back to Boston each weekend for the gigs that were paying his bills. Eager to soak up the New York scene, he’d return to New York on Sunday nights and go directly to jam sessions.
All that time back and forth on the Northeast Corridor paid off. A self-described musical “utility knife,” Cato’s multi-instrumentalism, as well as his talents as a songwriter, arranger, producer, and engineer, made him a major asset as a collaborator, and the New York scene took notice. Soon, he established essential connections that would affect his career, forming “an instantaneous brotherhood that continues to this day” with producer Kamaal Fareed, aka Q-Tip. “Through that, I ended up really delving into a lot of relationships and credits.”
The two artists worked on high-level collaborations that not only bolstered Cato’s reputation but served as a major piece of his education. “I’d show up to Tip’s,” he explains, “and we’d do a week of writing sessions with John Legend or have André 3000 in the studio for a couple of weeks. Sometimes things would come from it, and sometimes nothing would come from it. But being in the creative process on that level in a trusted space was invaluable for me. I learned so much.”
Outside of Q-Tip’s studio, Cato was learning from plenty of masters, mostly from behind the kit. “It’s really special when you find yourself learning things you connect to,” he says about his work alongside artists such as bassist Marcus Miller, keyboardist George Duke, and guitarist John Scofield. “And I learned so much about myself from connecting to some of these people.”
Staying Human
Back in 2015, Cato received a phone call from pianist Jon Batiste. The two had never met, but Batiste rang him up about a mysterious project—a theme song for a TV show that he couldn’t disclose. “I had a wisdom tooth appointment back in Boston, and I got a random call,” Cato remembers. “I think his exact words were, ‘I’d love to have your ears on it.’ And I followed my gut, rescheduled my trip, stayed in New York an extra day with an abscessed wisdom tooth.”
The two got together to co-write and produce “Humanism,” which would become the theme song for the Stephen Colbert-hosted Late Show. Batiste played piano, Cato played the guitar, bass, and drum parts and “put on my editing hat.” They brought in Joe Saylor—who would become the show’s drummer—to play tambourine, as well as saxophonist Eddie Barbash. “After the session,” Cato remembers, “I went back, got my wisdom tooth out, and went back on the road with John Scofield.”
Three of the four go-to guitars Cato uses on The Late Show: a black Tuttle T-style, a cherry-red Gibson SG, and a Martin OM-28.
At first, Cato played the multi-instrumental role of his dreams, attempting to surround himself with every instrument he could play. “That lasted about three days before reality set in,” he laughs. “Slowly, one by one, things started disappearing—a floor tom going away here, a Pro Tools setup going offstage there. Eventually, as the band formed out, I moved around to what was needed. I was the utility guy—played a lot of kazoo, a lot of cowbell.”
While on the road drumming with Sco’, Cato got the invite from Batiste to join the show’s band, Stay Human. “It was a huge life shift for me,” Cato explains. “I was making really good money on the road with really good musicians, which was really fulfilling. And I took a chance. I loved the idea of being a part of something creatively from its inception.”
Eventually, Cato settled into a more consistent electric bass role, until Batiste brought in upright player Endea Owens, and he moved to guitar, where he’s mostly stayed. When Batiste left the show last year, Cato took over as bandleader—officially starting this season, back in September—and decided he’d lead from his role as guitarist. “Of all the places I occupied,” he says, “guitar was the easiest and most natural to me to lead the band, in the energy. From behind the drums, it’s a different thing, and we’ve done it when Joe was out. But it just was a really natural progression.”
Same Show, New Job
In just a few months, Cato’s new role as bandleader has had an impact on the show. The renamed Late Show Band’s engine seems to be burning on a new kind of fuel. And it feels as though that energy is coming directly from Cato.
When we talk, the guitarist is deeply engaged, in a kind of hyper-focused way that is not intense but more casually un-distractable. He brings that same focus to the show. While Colbert delivers monologues, Cato is zoomed in on the host, listening to every word, often riffing around on his guitar to contribute musical commentary. During interviews, he’s taking cues and following the tone of the conversation, looking for ways to adapt.
The bandleader gig requires loads of big-picture improvisation, but also lots of prep. Cato explains that each week he makes a set list, but the band will react and make changes in the moment. “My job ends up being a lot of judgement calls that affect the flow of the show,” he says. “We have a group of compositions we wrote for the show that can complement different moments. If there’s a major energy shift in an interview that takes a turn or something happens in the day, like a tragedy, we’ll call one of the songs we wrote for the show for a moment such as that. Recently, we had a guest on that started improvising a song. So, I have on our in-ear mic and call out the key and start playing, and we all jump in, and now we’re doing this instead.”
Cato poses with his black-sparkle chambered T-style, made by Tuttle. “When I’m checking off core priorities in sound,” he says, “if I’m going for rhythmic things, I go to the Tele.”
Photo by Scott Kowalchyk
Watching the Late Show Band in person, I see this play out as Treasury Secretary Janet Yellen explains the steps the U.S. can take to avoid a recession. It’s a heavy and heady conversation, and, frankly, it’s anything but fun. Cato knows he’ll need to pick the audience back up. As he watches from the bandstand, he gives tempo cues to the band, who nod along, so they can effectively shift the energy and get the audience re-focused for the next guest, actor/director Sarah Polley.
As a guitar player, Cato says he sticks to playing things that feel most natural to him so he can concentrate on his bandleading duties. He adds that he considers himself more a rhythm guitarist than a lead guitarist. (It’s worth noting that his delineation is more conceptual than musical: Cato is an inspired and dynamic melodic lead player, but his deeply rooted phrasing and feel is at the forefront of everything he plays, so the rhythm-first thing applies to it all.) “This is not a space as a guitar player where I’m jumping out of the box trying any and everything and exploring,” he explains. “You get to some of those places. But for me, it always has to start from something I can do while leading the band and reading the energy and making judgement calls.”
“We’re arranging it and making it our own—because that’s the sonic fingerprint of our show.”
That rooted, pragmatic ethos applies to the gear he chooses as well. “I never was a big gear person,” he admits. Luckily, he has Late Show Band tech and informed gearhead Matt Mead to help him keep his pedalboard well-stocked. “There’s so many things I’m learning about the job and trying to keep straight in my head that this ends up getting the short end of the stick, and it wouldn’t work if there was not a Matt Mead to make up the rest of that stick and make it sound good.”
“The show throws a lot of curveballs,” Mead points out. “He steers the boat as far as the tones he’s looking for and if there’s a particular sound he’s looking for. Sometimes, I’ll recommend stuff and say, ‘Hey I notice you’re doing this, maybe we should try this.’”
Cato’s collaboratively curated pedalboard is pretty simple at its core: It starts with a Boss FV-500H volume pedal, a Boss TU-3, a Dunlop Cry Baby, and 3 Leaf Audio Octabvre. Cato shows me how he uses the latter for more traditional, Hendrix-style playing, but he points out that the band plays a lot of montunoes, and he tends to use the octave pedal for those. For drive, he uses a J. Rockett Archer and a Truetone Jekyll & Hyde, which are followed by an Xotic RC Booster and an MXR Carbon Copy, all into a Fender ’65 Princeton Reverb reissue, and powered by a Voodoo Labs Pedal Power Plus.
In live performances outside of The Late Show, Cato uses various guitars, but says that the studio’s cold temperature doesn’t do many favors for instruments such as his Gibson Luther Dickinson ES-335 or some of his acoustics, so he’s careful when selecting which guitars come on stage at the Ed Sullivan Theater. The three guitars that most commonly appear on the show are his black Tuttle Custom Hollow T, a cherry red Gibson SG 1961 Reissue, and a Martin OM-28.
Another guitar that sometimes appears on the Late Show is his LP-style Univox, which I ask Cato about in his dressing room. “If I need to be altogether comfortable,” he explains, “I pull out the Univox, because it’s my earliest guitar. I’ve had this since high school.”
Cory Wong "Lunchtime" - The Late Show's Commercial Breakdown
When musical guests visit The Late Show, they get the full-band treatment from Cato and company. Here, Cory Wong sits in for a rhythm guitar showdown of the highest level.
Back when he first got the guitar, Cato remembers, it was in rough shape, desperately in need of wiring and pickup repairs and a new set of tuners. It stayed that way until he was in Boston. When he picked up a wedding band gig playing trombone and guitar, he was lucky enough to have a roommate who could get the Univox performance-ready by replacing the original tuners with locking units, cleaning out the electronics, and swapping the pickups for a pair of Seymour Duncans.
“I didn’t even know there was a such thing as a professional musician.”
But Cato says that even before those repairs, he’s always “loved it because it’s all I had. I remember I was playing a little Vox amp, and this guitar had a feeling out of that amp. This guitar just became home base and felt super natural to my fingers. If I need to just not be thinking at all, this is home.”
Did he ever dream he’d be on television every night, holding this Univox and chumming with a late-night host? “Never! Not once!” he says. “It was just a product of my nurture growing up in a small town. I didn’t even know there was such a thing as a professional musician.” And yet, Cato pursued music as fully and single-mindedly as he could. “I just knew that I liked it and felt connected to it.”
What happens when a Deluxe Reverb meets an Electro-Voice EVM12L?
After seeing a recent video by Paul Rivera on the subject, I’ve become fascinated by the interesting relationship between the Electro-Voice EVM12L and the blackface Fender Deluxe Reverb amp. I’ve known Paul since filling the chief amp-tech position at Valley Arts Guitars that he vacated back in 1979, so I rang him up to find out more. Rivera helped establish Valley Arts as the go-to hub for pro players in Southern California, and it is here that my career in amp design began to take shape.
On the phone, Paul basically reiterated what he’d said in the video and, in typical Rivera fashion, he encouraged—make that challenged—me: “Go get a Deluxe and an EV and do some measurements.” That I did, and with the kind cooperation of jazz/funk king Paul Jackson Jr., for the speaker, and Joe Gamble, a frequent Fryette demo-video producer who provided an excellent early ’60s Deluxe, I was on my way.
Before we take the deep dive, let’s look at the context in which the Deluxe came into being. Intended as a student model, and hitting the market just prior to mass adoption of distortion as a sonic device, the Deluxe Reverb came with a low-powered 12" speaker fitted with a 20-ounce magnet. This cost-conscious production choice no doubt presumed that in those days one simply didn’t turn the volume past 3 or 4. However, as players began to explore the territory beyond 3, they also ran up against the consequences of doing so. Enter the speaker upgrade.
The iconic blackface Deluxe certainly has its own thing going, and although the current ’65 reissue comes stock with a 100-watt Jensen C12K, much of the original Deluxe mojo was defined by its strikingly underpowered speaker. Naturally, the minute you replace that with even a moderately more robust unit, the sonic signature that the stock, small-motor speaker is hiding comes roaring to the fore. I should note that for this experiment, I started by installing a custom, Fryette-spec Eminence P75 speaker. With its reasonable weight and typical power-handling capacity, this speaker turns the stock Deluxe into a much more versatile and giggable combo than before. It also provided a nice point of reference, being a well-known and fully documented entity, for this exercise. If you’re inclined to experiment, having a solid baseline is extremely important.
During the Valley Arts heyday of the ’70s and early ’80s, replacement speaker options were rather limited and mostly aimed at increasing clarity and reliability. The JBL D120 and Altec 417B were two of the most popular options of the era. The D120 was notable for its bold midrange and penetrating top end—a prominent feature of the Allman Brothers’ guitar sound, as fitted into a Marshall 4x12 cab. D120s had a distinctive—and to some ears, annoying—nasal chirp due in part to the signature aluminum dustcap. You may be surprised to know that those D-series speakers were alnico types, and for all their robust engineering, were fairly easy to blow in an open-back cab.
Rumor has it that the Allmans took the backs off their JBL-loaded 4x12 cabs in those days, not only because, as many believed, that made it easy to replace speakers, but because the D120s projected so much better than the stock Celestions that the band needed to dissipate some of that sound pressure out the back. This, by the way, also made for a much more ambient playing experience onstage. I should know. I once tried running a 100-watt amp into a 4x12 Greenback cab with its back off. While the reflected sound was a boon to my live gigging setup, I promptly blew 3 of the 4 speakers. Since these high-performance replacement options were out of my price range at the time, the originals got re-coned and I reinstalled the back on my 4x12 cab.
Also featuring alnico magnets and metal dustcaps, the 417B was made famous by Carlos Santana. Mick Taylor used 417Bs with the Stones in the early ’70s, and later Randy Rhoads used them with Ozzy. Both the D120 and 417B had strong personalities, and they were as sought after by some as they were shunned by others for being somewhat overbearing on top.
Electro-Voice was already in the game with their SRO series, but with the advent of the EVM12L, there at last was an alternative that was supremely reliable and sonically appealing to a wide variety of players. As such, the 12L became widely adopted as the dominant workhorse speaker—so much so that it soon found its way into just about every amp available at the time, including the very portable Deluxe Reverb, due in no small part to Rivera’s tenure at Valley Arts.
With its very large magnet, relatively low inductance, and aluminum-wound voice coil, along with the stiff cone, large dustcap, and compliant suspension, the EVM12L seemed to be just the right recipe to counter the flubby low end, scooped mids, and brittle top end one finds in the stock Deluxe with a typical speaker “upgrade.” That assessment still holds surprisingly true, though installing a 20-pound speaker in a 40-pound amp seems counterintuitive today. Contrary to what one might expect, the 12L brings out the pleasing sparkle and warmth of the Deluxe without sounding too piercing on top or too muddy on the low end.
After a fair bit of research and testing, and having spent considerable time delving into speaker inductance and reactive loads, I ran some of my observations by Eminence speaker designer Anthony Lucas. Here’s what he had to say:
“Inductance is certainly a part of what you’re hearing with the EVM12L in the blackface Deluxe, but not everything … maybe not even the most significant part. With its 20-ounce magnet and lightweight paper cone, the stock speaker is both coloring and limiting what the amp can do. It’s much more a part of the tone-creating process, like it or not, because this speaker has more limitations and likely a lot more peaks and dips in response. With its pro-audio cone, the EVM12L offers flatter response, minimal-to-no speaker breakup, and a much broader frequency-response range (down to 55 Hz). The 12L can handle the amp’s low-frequency range without getting muddy and breaking up, and it retains the amp’s clarity. You basically get out what you put in because with its 2.5" voice coil and 80-ounce magnet, the speaker is essentially overkill for the application and it delivers as full a range as physically possible.”
That last tidbit—“as full a range as physically possible”—offers a clue to the nicely tailored top-end response of the 12L-equipped Deluxe. In short, the substantial moving mass embodied in the 12L’s cone/voice coil/suspension assembly is certainly going to inhibit extended top-end response, and this is borne out in the speaker’s graph. You see an unusually smooth curve from 100 Hz to 2 kHz, a nice presence peak at 5 kHz, followed by a steep drop-off with little of the top-end nasties normally present in a guitar speaker.
The reason I find this combination so intriguing is that paired with an amp where much more attention is paid to the balance and synergy of the individual components and speaker, the EVM12L can be surprisingly disappointing. Yet in the Deluxe, the 6V6 power tubes driving an otherwise modest output transformer are allowed pretty much free rein to do their magic, while being massaged and refined by a speaker whose engineers probably never considered this a likely application for their considerable design effort.
In the ’70s and ’80s, when LA’s studio A-listers were schlepping their gear to several sessions a day, and probably a club gig at night, this versatile, high-performance little package—beefed up with a few of the must-have Rivera mods of the time—was considered practically indispensable, and helped launch the portable powerhouse-amp revolution.
So, should you consider installing such a massive appendage into an otherwise reasonably portable combo amp today? Only your chiropractor knows for sure, but if you can fairly well establish that any sonic roadblocks in your amp are likely caused by the stock speaker, it’s certainly a worthwhile and potentially enlightening experiment.
Discover which three elements of a guitar speaker have the biggest impact on tone.
When building a guitar speaker, one can make 101 micro-adjustments, whether it’s an extra turn of coil wire here or a thicker bead of glue there. However, these things are secondary to the three key elements that control most of a speaker’s tone, and it’s the speaker designer’s prime directive to get these three elements working together in harmony.
The membrane. Chief among these things is the sound-producing membrane—the cone. Guitar speaker cones are (still!) made from pulped and chemically treated paper pressed into the conical shape we’re all familiar with. After all these years, we still use paper because it provides the attributes we need: It’s lightweight, relatively (but not too) rigid, easy to shape, and cost-effective to produce.
Despite being made of humble materials, the cone is by no means a simple thing, and we can introduce variation into its production to control tonality. Thickness of the membrane is important. I’ve already touched on this in a previous column, but it bears highlighting again: A thinner cone deforms more easily under the pressure caused by coil movement. If you make the cone thicker, it becomes more resistant to those forces. However, these “deformations” are part of what contributes to the speaker’s tone. The skill of the speaker designer is to make a cone that’s thin enough to produce a musical tonality, while still being strong enough to withstand the application of a satisfyingly powerful kerrang.
The shape of the cone itself is also interesting. Way back in the days of radio, when a 1-watt amp was as powerful as you could get, straight-sided cones were used to tease as much output from the system as possible. The geometry of a straight-sided cone made it stiffer, so it could be constructed lighter, which enabled greater sensitivity and thus higher output.
It turns out that if you put enough signal into a speaker with a straight-sided cone, it eventually reaches a point where it suddenly and very quickly breaks up and resonates. Any audiophiles worth their salt would likely cover their ears in disgust, but that’s what we guitar players know as tone. And this explains why the modern guitar speaker evolved from the old-fashioned, straight-sided radiogram speaker.
Poles apart. When Celestion first started making moving-coil speakers for guitar amps in the late ’50s, we used an alnico magnet. This was the most commonly available technology at the time and what was used for all loudspeakers, regardless of application.
Forward to the 1960s and alnico became increasingly difficult to source, so guitar speakers were made instead with an iron-based ceramic magnet. While it was relatively simple to replicate the amount of magnetic force of an alnico magnet with the ceramic material, the two magnet types produced a noticeably different tone.
With its more aggressive, in-your-face sound, coupled with a high-end “graininess,” the ceramic magnet assembly was perfect for the music that rock ’n’ roll was evolving into during the ’60s. Compare this to alnico, which was relatively laid-back in its attack and delivered an overall smoother feel and a distinct chime at the top end.
After further experimentation, engineers and designers discovered just how much the size of the magnet affected tonality. By the end of the ’60s, Celestion offered their original ceramic guitar speaker in three different magnet sizes: the 50-ounce H (heavy), 35-ounce M (medium), and 20-ounce L (light). As magnet weight increases, so does the control of voice coil and cone movement. This has the effect of tightening the bass end and adding extra aggression in the vocal range.
In recent years, neodymium has become another magnet material used for guitar speakers. It’s very powerful for its size, and if properly controlled, neodymium can be used to provide a tonality that’s somewhere between that of ceramic and alnico, but with an additional level of note separation and fidelity that many consider desirable.
Wind me up. The voice coil is a length of copper wire wound around a “former.” It’s the moving part of the speaker’s motor whose configuration and performance is very much wrapped up in the amount of power a designer can make a speaker capable of withstanding. This, too, affects tone.
Consider the coil-former material: A paper former, as used in the 1950s, is less heat resistant than, say, fiberglass. The difference in material properties will impact the speaker’s tolerance of heat, which contributes to overall power rating (heat resistance directly correlates to power handling). And because various former materials sound different, this too contributes to the speaker’s tonal character.
Just as important is the diameter of the voice coil. A smaller coil flexes less than a larger one, but results in a larger cone length (the distance between cone neck to surround), meaning the cone is more likely to bend. A bigger coil will flex more, but the cone length is shorter, which means the cone is geometrically stiffer. A smaller coil will also have less mass and less inductance. All these physical attributes impact the sonic signature. Smaller coil speakers tend to feel brighter and break up more aggressively. Their fans consider them to be “sparkly,” whereas detractors would say they were “lightweight.”
More than anything, speaker tone is a direct result of a bunch of physical processes doing different things all at the same time. The better we can get these individual elements to work together in concert, the more desirable the resulting tone.
An aluminum dome looks pretty under stage lights, but it has an important job: protect the voice coil (left) and dissipate heat.
Does the humble dustcap affect your sound? Here’s what you need to know.
“Hey man, I really like your guitar box thing."
“Oh, my amp? It's a '72 Fender Twin Reverb. I put new tubes in it, re-capped it, and modded the circuit for more—"
“Yeah, yeah, yeah, but I just really like the way you can see the metal dome or whatever through the grille. That looks so cool."
“Oh yeah, those are the original JBL speakers that came with—"
“Well, see ya later."
I'm sure a similar conversation has occurred many times between thousands of guitarists and bar-goers. Between gear geeks and non-musicians. And probably between thousands of other people who may not realize that the “metal dome or whatever" has a significant effect on the tone of the speaker (self-professed gear geeks included).
As we've learned previously in Speaker Geeks, the cone is responsible for the lion's share of a speaker's tone. In the center of the cone is an opening where the voice coil is attached, and the voice coil sits inside a gap created by the speaker's front plate and magnet pole. It is vital that the voice coil doesn't rub against either part. It's also very important that no foreign particles can get inside and wreak havoc. Enter the dustcap, so named because it prevents dust from getting in this gap.
Call it a dustcap, dustcover, dome, or any other word that begins with D, the primary function is to keep dust and debris out of the inner workings of the speaker. But as early speaker designers quickly learned, the shape, size, and material of the dustcap play a huge role in a speaker's sound, specifically the high end.
It's important to note that most of the treble comes from the center of the speaker, beaming out from the top of the magnet pole. As the sound waves travel from the center and up the cone and radiate out, any ribs or ridges in the cone also send treble forward and into your ears. Some of the earliest designs, like the '50s Jensen P10R, used a piece of felt as the dustcap. Standing guard against those pesky particles, it got the job done, but it wasn't terribly sophisticated. This type of material absorbs a lot of the high end and results in a warmer sound without a whole lot of detail.
In the late '50s and into the '60s, speakers saw a lot of development and experimentation. Some speakers were built with hard fiber dustcaps like you might see on a vintage C12Q or C12N. This harder material deflects some treble, but allows the majority to pass through and provide plenty of detail.
Another type of dome is a large screen, which diffuses much of the high end and provides a warmer sound. Its dome shape spreads out the highs more evenly. The larger size also means a greater distance from the magnet pole, so the treble hits the material a little farther out, which also helps with the diffusion. Many harmonica players like this kind of dome, because highs cause feedback, and a screen dome helps reduce or eliminate that.
The other big dustcap is the aforementioned metal dome, which is typically made of aluminum because of its heat-dispersing attributes. When you play guitar, the amp's output signal travels to the speaker where it is converted to electromagnetic energy to make the voice coil move … and heat. The latter builds up in the voice coil gap, which is usually no problem when you have a speaker with a higher power rating than the amp puts out. However, with larger amps that put out more power, the heat resistance of the voice coil material alone may not be enough. Different techniques are used to combat that heat buildup, including venting the heat out the back through a screen, through holes in the voice coil, or sometimes through vents in the dustcap itself. Aluminum domes have sufficient heat-resistance properties to stave off heat without a vent—at least the amount of heat we're talking about.
So you'll typically see aluminum domes on amps with high output ratings, like the Fender Twin Reverb, at 85 to 100 watts, and the Roland Jazz Chorus at 120 watts. And those domes sure look cool—especially on a stage with lights reflecting off them. Dazzling. But as anyone who has ever played a speaker with an aluminum dome knows, the high end can be pretty crispy. The hard aluminum material extends the high frequency range, too. Where a typical guitar speaker falls off around 5 kHz, an aluminum-domed speaker can go as high as 7 kHz. This extended high end can sound very pleasing for certain music, such as some jazz and surf, where the tone is uncompromisingly clean. But when you start adding overdrive, watch out. It can very quickly sound like a swarm of bees.
Maybe you want that kind of tone. Who am I to judge? But now at least you know there's more to a metal dome than its pretty looks, so you can make an informed decision on your next speaker acquisition.