By the 1980s, many manufacturers emphasized rackmountable effects, such as the A/DA STD-1 (top)
and Ibanez’s AD-230 (bottom), a multi-effect monster with 18 BBD chips.

The Digital Revolution
By the end of the ’70s, two major effects-market shifts began unfolding. First, manufacturers started to focus more on rackmount products and less on stompboxes. This was coupled with a growing movement in favor of newly emerging digital technology. As a result, the next wave of classic delay units was mostly rack devices.

Initially, some of these products used analog BBD circuitry. A/DA entered the market in 1978 with a line of stompboxes, beginning with the legendary A/DA Flanger, but by ’81 it had switched exclusively to rackmount products. One of its early rack units, the STD-1 Stereo Tapped Delay, was a high-quality, BBD analog delay. And though Boss (a division of the Roland Corporation) and Ibanez continued producing effect pedals during the ’80s, each also had its share of rackmounts. The mother of all vintage Ibanez rack effects was the Ibanez AD-230 Analog Delay and Multi-Flanger, a studio-quality unit that used 18 Panasonic MN3004 BBDs.

But within a couple of years, even the analog rack delay would become a relic of the past. With their relatively low fidelity and inherent loss of high-end frequencies, bucket-brigade delays were no match for the crystal-clear repeats of a digitally sampled signal. Digital technology was the way of the future.

Eventide Clock Works Inc.—today known simply as Eventide—was one of the first companies on the digital signal-processing scene. Its legendary H910 Harmonizer, which debuted in 1975, featured pitch shifting and a short digital delay, with feedback control for creating doubling effects. In 1979, Mu-Tron’s Digital Delay arrived, although it was short lived due to the fact that the company had just been purchased by ARP, which went under the following year.

The early to mid ’80s brought some of the most highly regarded digital delays ever produced. Lexicon, which was already breaking new ground with the 224 Digital Reverberator, introduced the PCM 41 Digital Delay Processor in 1980. It was the first in a series of world-class digital delays that would also include the PCM 42 and PCM 70.

The Digital Delay (top) was one of Mu-Tron’s final products before folding in 1980.
Meanwhile, Korg’s SDD-3000 (bottom) gave the Edge his echoes.

In 1982, Korg debuted the SDD-3000 Programmable Digital Delay, which quickly became integral to the signature sound of U2’s the Edge. Around the same time, Roland released the SDE-3000 Digital Delay, a rack that was on par with the Korg but that now commands less than half the price on the vintage market ostensibly due to the lack of celebrity association.

In 1984, players who wanted digital delay in a stompbox finally had access in Electro-Harmonix’s 16-Second Digital Delay—a pedal that King Crimson guitarist Adrian Belew made extensive use of, especially for its looping capabilities.

Eventide scored big in 1985 with the H3000 Ultra Harmonizer, a state-of-the-art processor with algorithms for creating pitch shifting, delay, and modulation effects that had never been heard before. The H3000 quickly became a must have for broadcast and recording professionals.

TC Electronics TC2290 Dynamic Digital Delay + Effects Control Processor, released in 1986, is one of my all time favorite delays of any kind — fantastic sound quality, great modulation, packed with features, easy to program, and the best looking display a rack unit could have.

Rackmount gear was fully established by the late ’80s and dominated the scene in the early ’90s—this was the heyday of digital multi-effects units. However, most multi-effects units of the era seemed to concentrate on quantity—numbers of effect types and preset-storage slots—rather than quality. The focus of manufacturers trying to develop products that delivered the most bang for the buck resulted in the cheap, over-processed guitar tones that began to give digital a bad rap.

The Seattle grunge movement of the ’90s helped shift players’ attention back to analog stompboxes, creating an interest in “vintage” pedals and helping to foster a new cottage industry of first-generation boutique pedal makers. But while more pedals were becoming available, delay was an underrepresented effect in the ’90s stompbox scene. Programmable rack delays still had it over stompboxes in terms of options and flexibility. One of the better delay-pedal options toward the end of the decade would have been something like the Boss DD-5 Digital Delay. Over the next decade, things became a whole lot different.