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more... GearHow-TosEffectsPedal ProjectsRepairDelayGear HistoryFebruary 2017

Behind the Bucket Brigade

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Before BBD chips, time-staggered effects like flanging, chorus, echo, and double-tracking were only possible with magnetic-tape-driven units such as the Echoplex EP-3 (left) and Roland Space Echo RE-201, while rotary-speaker effects required a literal rotating-speaker array like the Leslie setup shown here in a transparent acrylic cabinet.
Photos courtesy of Tom Hughes

Is there a 15-year-old out there who’s never dreamed of having a time machine—a hi-tech contraption that’d take you back in time 10 minutes to avoid the botched joke that ruined your chances with so-and-so, or maybe to think twice about that failed guitar twirl that obliterated mom’s favorite lamp? Or, even better, beam you into the future, Biff Tannen-style, so you can ferret-out bankable sports bets—or just skip the rest of high school altogether! It’s a silly fantasy, yet one we never completely outgrow over the post-teen decades.

The funny thing is, in a sense, time machines have existed since the early 1970s. They may not have had all the bells and whistles we dream of, they may not have come with a clever talking dog who explained all the new sci-fi awesomeness for us—and heck, they didn’t even take you into the future—but they still existed in the form of delay/echo units. The first such “time machines,” at least in terms of mainstream availability and affordability, came out back during the bell-bottom decade—and they were powered by another hyphenated double-B technology: “bucket-brigade” chips.

If you’ve been playing guitar for a while, you’ve no doubt heard a lot of hoodoo and voodoo about expensive vintage bucket-brigade effects pedals and processors over the years, but even players with fewer axe-wielding years under their belts have likely seen and heard a fair amount about devices powered by modern renditions of this once-dead, now-resurrected circuitry. Which is why we’re offering this handy-dandy guide to help you understand bucket-brigade devices (BBDs) from then and now.

So What Exactly Are BBDs?
Bucket-brigade devices were the first wholly electronic devices for producing time-delay of electronic signals. Prior to their development, most effects that time-staggered an audio signal relied on magnetic tape and manipulation of tape speed. (Examples include the various iterations of the Echoplex and Roland’s Space Echo.) BBDs permitted easier production of echo and effects like flanging, chorus, and double-tracking from a much smaller device. Further, BBD effectors enabled flanging to be produced onstage without the prior need for two tape decks, and rotary-speaker-like effects were possible without lugging around a massive Leslie setup.


The original Boss CE-1 Chorus Ensemble was a classic early BBD-driven chorus stompbox.
Photo courtesy of Spaghetti Vintage

Between the late 1970s and mid 1980s, many classic BBD-based effects were issued, including the Boss CE-1 Chorus Ensemble and CE-2 Chorus; flangers like those from Electro-Harmonix, A/DA, and MXR; and delays like the Electro-Harmonix Deluxe Memory Man and Boss DM-2—not to mention desktop and rackmount delays and multi-effectors like the Ibanez AD-230 and MXR Flanger/Doubler. BBDs would also find their way into synthesizers, mixers, and even karaoke machines. Eventually, many of these effects—particularly the delays—would become replaced by digital units, largely because of the latter’s greater delay capacity. But the demise of original BBD effects was also due to the fact that the principal manufacturers—Matsushita (now known as Panasonic), Reticon, and Philips Research Laboratories—eventually ceased production. Even so, musicians’ affection for analog BBDs never really went away.


But MXR’s Flanger/Doubler was an BBD processor found in studios during the early ’80s.
Photo courtesy of Vintage and Rare/Soundgas

Despite the fact that both entry-level and high-end digital multi-effect units became all the rage during the ’80s (with players like U2’s the Edge, Steve Vai, and Eddie Van Halen becoming notorious for their “refrigerator stacks” full of rackmounted digital gear), a small segment of devoted players never gave up on the “warm,” classic sound of analog gear. As the 1990s wore on, new boutique pedals powered by new-old-stock (NOS) BBD components (for example, Moogerfooger’s MF-104M Analog Delay) started to build the buzz anew—although at a premium price, and often in very limited runs. Beginning slowly in the early 2000s, and picking up the pace considerably in 2015, a new generation of much more affordable BBD-driven pedals has been made possible thanks to companies like Coolaudio, Belling, and Xvive Audio producing accurate replicas of original BBD chips.

Much like classic 3-tube amplifiers of yore—amps like the Fender Champ, with its basic preamp-tube, power-tube, and rectifier-tube circuit—there are common design aspects and considerations for nearly all effects that use BBDs. So let’s take a closer look at the nuts and bolts of how these magical chips work and how they’re used.

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