The Revolutionary Chip Inside Your Favorite New Pedals

If you’re a fan of crazy pedals that do radical pitch-shifting, micro-looping, ambient modulation, and granular delay, then—whether you know it or not—you’re probably a fan of the FV-1.

The FV-1 is an integrated circuit (IC) and digital signal processor (DSP) targeted at general audio effects. It is extremely customizable, and designers can either use its eight built-in programs or write their own and store them on what's called an external electrically-erasable programmable ROM, or EEPROM.

But wait: before your eyes glaze over, know that the FV-1 changed everything.

Spin Semiconductor released the chip in 2006, and companies took to it immediately. Enabling sounds like warped polyphonic harmonies and spatial delays that were never before possible, Electro-Harmonix used it on their first multi-effects pedal, the Holy Stain, and EarthQuaker Devices uses it on the Dispatch Master and Rainbow Machine.

Engineers were—and are—drawn to the chip for its ability to program audio expansion and compression routines (the process by which data is expanded or compressed). Plus, they can incorporate integrated digital LFOs and ramp generators to program things like multi-voiced pitch-shifting, reverb, and outrageous delay.

The Creation of the FV-1

The FV-1 was the last major innovation of legendary audio engineer Keith Barr, who died in 2010.

Barr co-founded MXR with his friend from high school, Terry Sherwood, in 1972 and was behind the design of devices like the Phase 90, Dyna Comp, and Blue Box. According to the Dunlop website, these hall-of-fame effects were initially assembled in a basement and sold out of a car at local shows when bands came to town.

Barr launched his second company, Alesis, in 1984 with an initial roster of inexpensive digital reverbs. In 1991, the Alesis Digital Audio Tape machine (ADAT)—the first affordable digital multitrack recorder—made its debut. The ADAT deserves an article in and of itself.

It was at Alesis where Barr met Frank Thomson, who began working for the brand in 1991 as part of an R&D group doing application-specific integrated circuit design (ASIC). "My desk was right outside of Keith's office," Thomson says. Such proximity and his penchant for developing great DSP chips (like those found in the ADAT and effects processors like QuadraVerb 2) would soon lead to the development of the FV-1.

Thomson is currently CEO of the Experimental Noize pedal and pro audio company. He also oversees production, planning, shipping, and tech support for Spin Semiconductor on behalf of Barr’s widow.

"Keith was actually very cool. He would stop to look at what I was working on and ask questions about design choices I made. My first design was the S4DSP ASIC used in the QuadraSynth keyboards. That worked out well, so he would often talk to me about other ideas he had for other digital products."

Thomson continues: "After Alesis was acquired [by Jack O'Donnell in 2001], we both worked in different areas, but remained in contact. I was able to get a NAMM pass each year, so I kept attending and over time realized there was a demand for a DSP targeted at reverb, delay, and things like that. I talked with Keith about it, and he started Spin Semiconductor to fund and create the chip. I was contracted to work on the design with him, which was eventually created and brought to market.”

How the FV-1 Is Used

Now that we know the history of the chip, let's see what engineers can do with it.

In this roundup, we showcase an array of idiosyncratic pedals that show off the FV-1’s capabilities, which are seemingly endless. The chip enables functions that range from the ridiculous to the sublime, and according to some, may represent the last major advancement to impact the boutique pedal industry.

The SSD Atom Smasher is a glitch delay pedal that generates a potpourri of oddball noises like stutter and phrase capture, reverse ramp delay with ring modulation, various delays combined with octave glitches and pitch-shifting, and reverse reverb.

Alex Lynham, the company founder, wrote a Medium post about the intricacies of programing the FV-1. "The FV-1 uses a dialect of assembly [or basic assembly language] called SpinASM," he wrote. "You can write it in a text editor and compile it using a program that SpinSemi provide. However, if you’re looking to create more standard effects (chorus, phaser, reverb) for example, you might find that Digital Larry’s brilliant SpinCAD has what you need built in."

He continues: "In fact, I’d hazard a guess and say there’s probably a fair few commercial boutique pedals whose code was generated by SpinCAD rather than handwritten. For mucking around with reverb blocks and pre- and post-processing, I’ve found it to be lots of fun, and the glitch and pitch reverbs in the Atom Smasher were made using it."

The Chase Bliss Audio> Mood is a two-channel granular micro looper and delay, built in conjunction with Old Blood Noise Endeavors and DroloFx. "One thing I really love is that since so many DSP engineers use the FV-1 as a platform, it makes it a really friendly device for collaboration and creativity," says Chase Bliss founder and engineer Joel Korte.

Mood is split down the middle: The left side controls the OBNE choppy delays and reverbs, while the right side handles the Drolo granular loopers and tape-like functions. Each side was built around an FV-1, which was programmed by the respective designer. "Both were responsible for writing DSP code for one FV-1," Korte says. "I then controlled the routing and control of the chips."

As opposed to some of the other pedals in this roundup, which emphasize the weird, the Walrus Audio Arp-87 is a utilitarian workhorse.

It’s built around an FV-1 core, and Walrus took advantage of the platform’s versatility to program a diverse set of algorithms that offer digital, analog, lo-fi, and slap back options. (The FV-1 is also at the heart of the company's Fathom Reverb as well).

The Arp-87 was built without a time knob, and uses tap tempo—in conjunction with a ratio control—to determine delay speed. The pedal’s selling-point is a set of functional, traditional delays, although it can do some subtle warbles, warps, and darker tones, too.

Although the Absolüte Würst started as an April Fool’s joke, it is a serious pedal with a cult following among connoisseurs of the bizarre. Inspired by the DOD Gonkulator Ring Modulator, the Würst makes broken robot noises and unpredictable blurps and grunts.

Designer and company founder Robert Keeley took advantage of the FV-1’s highly programmable parameters and built functions like a random harmony generator, pitch-up ring modulation with tracking, and even something called the "drunken bass player."

The pedal generated a lot of buzz when it was first released and Nick Reinhart, of the rock band Tera Melos and the blog/YouTube channel, Pedals and Effects, listed it as one of his top pedals of 2015.

Unfortunately, it seems that Keeley since got cold feet and pulled the pedal. If you follow the link to the Absolüte Würst on the Keeley Electronics website, it takes you to this depressing 404 message. Used models do appear on Reverb from time to time.

The Black Hole Symmetry is the first offering from Collision Devices a (seemingly) standard-issue FV-1 derived unit, sans the glitches and stutters. But don’t be fooled: Black Hole Symmetry takes reverb and delay, mixes it with onboard fuzz, and creates something anomalous and new.

The reverb—in addition to producing breathy, ethereal soundscapes—combines with a pitch-shifting function to allow for edgy, angular sounds. The delay mode also modulates, which enables warbles and warps.

Plus, the circuit integrates with an internal fuzz, and when run in conjunction with the other sections, allows for everything from subtle synth-like sounds to sonic obliteration.

The Red Panda Tensor is a great example of the FV-1’s programmability and the wild diversity of available options. Part sampler, part pitch-shifting harmonizer, the Tensor can summon standard loops and whammy-type effects, reverse lines tracked in real time, tape stops and slow downs, time-stretching, and randomized stutters/glitches.

It’s set up so when you stretch or compress time, your pitch doesn’t change, and the loops can be run forwards, in reverse, alternating between the two, sped up, or slowed down in triple time. It does a lot more than that as well, but—and this holds true for the other unusual noise makers featured here—you really need to get one under your feet and explore it yourself.