Sweet Leaf

Who would have thought that what started out as an above average blues band would become the prototype for heavy metal as we know it. From the opening sounds of a rainstorm to a bell that’s tolled for a thousand lives to the perfect use of the Devil’s Interval, Black Sabbath had, perhaps inadvertently, created something coherent and unique that immediately registered and resonated with listeners upon first exposure.

So rare is that occurrence that when critics started complaining but fans started following, the band knew to continue in the direction they had started. And we are all glad they did. As album after album of instant classics continued to fill the shelves, many guitar players started to wonder how Tony Iommi was getting such a heavy sound. And so our journey begins…

What we do know is that Iommi had a modified Rangemaster, one of the first treble boosters. Based on dropping the needle and some experimentation, it’s unlikely that Iommi got that kind of distortion from an amplifier and a treble booster. Our latest theory is that his Rangemaster was modified to include a fuzz unit. Most likely a two or three transistor model since the Rangemaster itself was a single transistor circuit.

What we have here is the classic VG402B Amplifier with the VG 4x12B 100W ’73 Cabinet and the EQ100 Treble Boost followed by the FZ101B Fuzz. This deep and heavy tone is amazing and we think you’re going to instantly hear those Black Sabbath classics when playing. Paired with an SG, you can’t get any closer. Enjoy!

SWEETLEAF

Crank it up, this tone is heavy. Designed to imitate modifications done to Tony Iommi’s treble booster, we think we’ve found something special. But you be the judge. Use the fuzz to capture the dark sounds of Master of Reality or disengage and crank the amp for something brighter, similar to their self-titled debut.

  •  VG402B Amplifier
  • EQ100 Treble Boost
  • FZ101B Fuzz
  • VG 4x12B 100W ’73 Cabinet

Nevermind

Depending on your punk rock ethics, you may or may not have a lot to thank Mike Wallace for. Without question, his application of slick dance music production techniques to a new generation of punk willing to admit that they liked the Beatles helped define the sound of an era. Call it what you will, the music was infectious. Like songs you learned when you were a kid—they were easy to remember, enjoyable to sing along with, and aggressive and catchy as hell.

But Wallace was typically employed only as a mix engineer. He would get involved with projects after most of the material had already been recorded. In order to have such great material to work with, the raw energy in the studio still needed to be there. With Nirvana’s second album—their first on a major label—Wallace would create a blueprint for many bands to follow but first, the band needed to record an album. Enter Butch Vig. Having previously worked with Nirvana on some demos, he would become the vehicle through which the band would successfully get onto tape their pop infused ideas. Famously using John Lennon to coerce more takes, Vig knew exactly how to interact with underground artists.

Listening to the unmixed stems, it’s clear this album was meant to be raucous, heavy, and in your face. With AmpStamp, let’s take look at capturing that raw energy and giving it some slick studio production (or not, if you prefer). Here’s what we know:

  • Kurdt Cobain’s amp had broken at an earlier gig and the band used the money they had to purchase a Mesa Boogie Studio .22 preamp and a power amp
  • When the band checked in to Sound City studios, Kurt brought the Mesa Boogie with him. During recording he would also employ a Fender Bassman and some pedals but as Vig states, “Kurt Cobain, for the most part, used a Mesa Boogie amp”<sup>1</sup>
  • Based on live appearances, a modern Marshall 4×12 was used

NEVERMIND

Careful! This one is hot! You may want to engage the Squelch control (noise gate). Though we know Kurdt used a distortion pedal to switch between clean and distorted tones, we think you’ll hear similarities using the high gain channel on this amplifier, it definitely packs a punch better than any pedal. Change the Color to get different left and right channel takes, and voilà—never mind.

  • VG802C Amplifier, toggle between lead and clean + CH102 Chorus
  • CH102 Chorus
  • VG 4x12B 260W ’82 Cabinet
LITHIUM

Though not a Bassman, we think you’ll agree this sound is instant Grunge. With a thick quality unlike any modern amp, this was the secret ingredient to some of the moodier tracks on Nevermind. The tone is much darker so we’ve adjusted the Color for more brightness, but let your ears adjust to it, it’ll sit perfectly in a final mix.

  • VG207A Amplifier
  • FZ104A Fuzz
  • VG 1x12C 15W ’68 Cabinet

Woman Tone

Let’s take another quick look at one of the ultimate classic guitar tones, a sound Eric Clapton once described as “Woman Tone.” We’ll spare you the history of the band, but if you’re not aware, do yourself of favor and look them up. Better yet, get yourself acquainted with their music.

As part of their farewell concert, Clapton gave an interview where he described exactly how to get this sound. In his own words, either “by using the bass pickup, or the lead pickup but with all the bass off…on the tone control. Turn it down to one or ‘oh.'” Watch and learn from the man himself.

If you’re lucky enough to have an SG, Epiphone or otherwise, that will help. But a Strat can certainly come close when using the same pickup strategy. The elements are simple enough, we’ve lined up the perfect combination in AmpStamp.

SUNSHINE

For the rhythm tone, set the amp to direct output, bypassing the cabinet altogether. It’s likely this was done with the amp or a pedal, but you’ll instantly hear the clarity and top end that Clapton gets from his guitar. For the lead tone, use the neck pickup, or the bridge pickup with the tone down to zero, or to taste. You can’t miss this epic sound. Enjoy!

  • VG402B Amplifier set to use the Normal channel
  • VG 4x12A 100W ’67 Cabinet
  •  WH100 Wah
  •  AMB400 Plate Reverb

Killer Queen

Import Preset: Killer QueenImport Preset: Killer Queen

Let’s take a quick look at one of the ultimate classic guitar tones, the one and only Brian May of Queen. We’ll spare you the history of the band, but if you’re not aware, do yourself of favor and look them up. Better yet, get yourself acquainted with their music.

In a rare moment for this business, Brian actually cut a near 30 minute video back in 1983 detailing how he achieved his now legendary sound. If you have the time, we highly recommend watching it.

Here are a few key points that we gleaned from watching the master at work:

  • uses AC30’s without Top Boost, can achieve a similar tone by playing through the Normal channel
  • starts with a really woolly tone and refines it using a Dallas Rangemaster Treble Booster
  • plays with a metal pick
  • adds a chorus pedal using two or more amplifiers for true stereo operation
  • also adds a delay pedal panning repeats to opposite amplifiers

Oh right, and Brian’s guitar is obviously a one-of-a-kind! But that’s OK. We’ve lined up a few of the required elements in AmpStamp:

  • VG302E Amplifier set to use the Normal channel
  • EQ100 Treble Boost
  • VG 4x12B 100W ’73 Cabinet for rhythm tones
  • VG 2x12C 30W ’67 Cabinet for lead tones
Killer Queen

Disable the boost for mellow cleans, tap into solo mode for blistering leads, and enable echo to bring in other-worldly harmonies while soloing. This preset has you covered for all occasions. We’ve also added room ambience to capture the studio sound found on recordings of rock bands during the mid-’70’s. But enough talking for now, check out how it sounds!

Import Preset: Killer QueenImport Preset: Killer Queen

Classic Sounds: Phase Shifting

Welcome to the first installment of our Classic Sounds series. In this edition we are going to touch upon the history of products that first implemented the effect known as phase shifting and how you can achieve similar sounds with the Digital Filter.

Technology

Traditional phase shifting is accomplished by passing an input signal through a set of All-Pass filters in series and then summing the output with the original input. All-Pass filters do not attenuate the input but like Low- and High- Pass filters, they shift the phase of specific frequencies. Wherever the output is inverted or 180 degrees out of phase with the input signal, a notch will occur in the frequency spectrum. Modulating the corner frequency of these notches creates the effect we know as phase shifting. With two All-Pass filter stages in series, we expect one notch to be created at the corner frequency. As we increase the number of stages by 2*n, we can expect to add n more notches.

Fg. 1: All-Pass Filter Phase Response
Fg. 1: All-Pass Filter Phase Response

1968: Breaking New Ground

The first popular effect to make use of phase shifting was the UniVibe (Shin-ei). Released in 1968, this circuit design is the most unique of the products we considered. This effect has four filter stages but is not typical in that each stage is tuned differently. Furthermore, the signal used to modulate the filters is not a standard waveform. This was due to the use of light-dependent resistors (LDRs) and the associated limitations with turning the light source on and off.

Though three years later, Maestro is credited with releasing the first official phase shifter, the PS-1 (1971). This effect has six stages and uses field effect transistors for variable resistance to modulate the filters. Musitronics (Mu-Tron) was inspired by this design and created the Phasor (1972), built with Operational Transconductance Amplifiers (OTAs) which eliminate the need for FETs as they can be directly modulated via bias input.

1974: Year of the Phaser

The next most popular effect is the Phase 90 (MXR). Released in 1974 with just one knob, a product for musicians couldn’t get any simpler. This effect has four stages and later introduced an internal feedback resistor which added a mild distortion and increased filter resonance. MXR also released the Phase 45 (2-stage) and the Phase 100 (10-stage). The Phase 100 had a few additional features including applying modulation to a subset of the filter stages.

In the same year, Mu-Tron released the Bi-Phase (1974), a configurable series/parallel combination of two six-stage filter banks. Each modulation source is selectable between sine and square waveforms and can be synchronized.

Also in that year Electro-Harmonix released the Small Stone (1974). This effect has four stages and was technically the first to introduce feedback, controllable by a switch. Electro-Harmonix then released the Bad Stone (1975), revised from an earlier design. This effect has six stages, a dedicated feedback control, and a manual-mode with dedicated control of corner frequency.

1979-Present: Coming Up To Date

Later, A/DA released the Final Phase (1979), with six stages and steeper notches for a more pronounced effect. The Final Phase had an additional feature that added a second low(er) frequency oscillator to create more complex modulation schemes similar in concept to the Bi-Phase.

Fast forward to modern times and the release of the Moogerfooger MF-103 (1999), a selectable 6/12-stage filter, and the Boss PH-3 (2000) a selectable 4/8/10/12-stage filter with additional features including rise/fall and step modulation, and that sums up the history of phase shifting as we know it.

Not so fast, with the growing interest in Eurorack Modular gear, it’s worth mentioning Pittsburgh Modular and the release of their Phase Shifter (2014). This effect has sixteen stages and brings the experimental nature of modular synthesis along with it, providing custom ins and outs, switchable changes in configuration, and multiple taps.

Fig 2: Vital Statistics
Fig 2: Vital Statistics

Digital Filter

Though the Digital Filter is not a phase shifter by design, we were able to overcome these limitations by combining the output of both HP and LP filters. There was enough difference in phase to generate notches or cancellations at the appropriate locations in the frequency spectrum when summed with the original signal.

We built up a set of patches based on classic designs, including the unmistakable sound of the UniVibe, the dual configuration of the Bi-Phase, and the simple but effective Phase 90. The intent is that this is a starting point for experimentation. We hope you find something useful and inspiring.

Download the Phase Shifter Refill

Sources

• Hughes, Tom. Analog Man’s Guide To Vintage Effects. For Musicians Only Publishing, 2004. Print.
• Thompson, Art. Stompbox: A History Of Guitar Fuzzes, Flangers, Phasers, Echoes & Wah. Miller Freeman Books, 1997. Print.
The BOSS Book: The Ultimate Guide to the World’s Most Popular Compact Effects for Guitar. Hal Leonard Corporation, 2001. Print.
http://www.geofex.com/article_folders/univibe/univtech.htm
http://www.pedalarea.com/small_stone.htm