SPECTRASONICS Stylus RMX 1.2.1 (Mac/Win)

Though spontaneity is not often associated with loop sequencing, the quasi-improvisational capabilities of Spectrasonics' Stylus RMX are only part of
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FIG. 1: A variety of options appear on the Edit page of Spectrasonics'' Stylus RMX, one of which is its subtractive synthesis engine. Note the use of a synchronized triangle-wave LFO to modulate filter cutoff frequency on backbeats only, as shown in the Edit Group window.

Though spontaneity is not often associated with loop sequencing, the quasi-improvisational capabilities of Spectrasonics' Stylus RMX are only part of its many highlights. The plug-in has construction-kit-style loop layering and arranging, malleable playback features, a drum-kit mode with interchangeable kit pieces, and expandability. You can perform almost every edit and parameter change in real time and easily create animated, complex grooves within an ever-flowing context.

Spectrasonics' Stylus and Stylus RMX share some operational features, but RMX offers many new capabilities, such as an 8-part multitimbral engine, versatile built-in effects, and roughly three times the sample content of its predecessor. The program installer and sound content come on two DVDs, and a CD contains tutorials in QuickTime format. Once installed, the program will run in demo mode for four days before requiring a simple, Web-based challenge-and-response authorization.

The RMX Core Library expands on the theme of its predecessor with a concentration of highly processed (but adaptable) grooves suitable for dance, hip-hop, R&B, drum ‘n’ bass, funk, fusion, and even dramatic underscoring. Multis combine agile Groove Elements into textbook examples of layered, animated rhythms. The loops work well at a wide range of tempos — loops intended for tempos of 150 bpm take on new dimensions at 70 bpm, for example — especially with the intervention of the Spectrasonics Advanced Groove Engine (SAGE).

I tested Stylus RMX on a dual G4 1.42 GHz Mac using Ableton Live 4.04, Granted Software RAX 1.2.2, MOTU Digital Performer 4.5, and Steinberg Cubase SX 3.0. Stylus RMX supports Audio Units, VST2, and RTAS under OS X 10.2.6 and higher, and VST2 hosts on Windows 2000 and XP machines. According to Spectrasonics, a Windows RTAS version should be ready by the time you read this review.

SAGE Pages

The Stylus RMX multipage interface is a model of efficient and intuitive design. Four main pages have controls to shape loops in different ways. The Edit page has assorted synthesis options (see Fig. 1); Chaos Designer creates and controls rhythmic, reverse-play, temporal, pitch, and dynamic variations; and FX hosts the plug-in's built-in DSP. The Mixer page lets you balance the parts, assign outputs, and control auxiliary effects. Each of the eight parts has its own Edit, Chaos, and FX pages.

Every page of every part shares the Footer area, whose parameters are common to all. Two rows of eight buttons appear at the bottom of the Footer — one is used to select a part, and the other enables or defeats playback of individual parts. Four larger buttons call up the Edit, Chaos, FX, and Mixer pages. In the Footer, you are never more than a click away from any page or part.

The Footer contains a stereo level meter and a Master fader that governs the plug-in's overall level. Master Start and Stop buttons control playback with or without benefit of the host. An informational display lets you monitor parameter values, the amount of RAM occupied by the loops, received MIDI Control Change messages, and more. Other options in the Footer govern each part's response to MIDI data, and a Utility menu offers additional program options such as copying and pasting parameters or assigning MIDI Control Change messages.

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FIG. 2: The browser window is instantly accessible from any other page and lets you audition loops on the fly. Note the drag-and-drop MIDI file area and buttons that let you double or halve the speed of the loop.

To access core-, user-, or expansion-library sounds, click on the loop title or any folder icon (see Fig. 2). The browser offers more features than its name implies. Here you select Suites, which are collections of related grooves, and Elements, which are grooves that make up a Suite. Clicking on any Element engages its playback, and you can combine Elements from any Suites that you choose. The Speed section lets you multiply or divide any part's playback speed by two — because the grooves are sliced, there are no inherent time-stretching artifacts.

The MIDI File section holds the data that triggers individual loop slices, and you can easily edit that data by dragging-and-dropping it into one of your host's MIDI tracks (that process is unidirectional). The Settings button lets you audition and apply current synthesis, Chaos, and effects edits to a loop. From the Favorites section, you can create, edit, or jump to a list of frequently used grooves.

Grille of My Dreams

A click on the grille in the Edit, Chaos, or FX page opens the Edit Group section, which contains the program's most powerful features. An Edit Group is a user-definable loop region, which can be an entire groove, an individual slice, all upbeats or downbeats, or events landing on any rhythmic subdivision as high as a 96th note. CPU willing, every Edit Group can have its own synthesis, Chaos, effects, and other settings. On a single stereo loop, for example, you could apply reverb to snare hits on beats two and four, lower the cutoff frequency and raise the resonance of kicks on downbeats, add Chaos and synchronized-LFO panning to hi-hats, or reverse tom hits.

The upper Edit Group window offers access to Groups created from the Assign menu. Using utilities embedded in the Assign menu, you can create an Edit Group for every groove contained in a Suite and for each slice in an Element. You can also clear an Element from a Group. Individual Edit Groups can be toggled on or off or soloed or muted, and you can assign a Group to any of eight stereo outputs if your host supports that number.

The Edit page (as opposed to an Edit Group) hosts RMX's subtractive-synthesis engine (see Fig. 1). Horizontal faders at the far left have controls for level and Pan Position. To the right are buttons for setting Amp, Filter, and Pan LFOs. You can control rate and depth for each LFO, and choose sine, triangle, square, pulse wave, up or down sawtooth, or sample-and-hold shapes. LFOs can run free or sync to your host's tempo, making bpm-based pan, filter, and tremolo effects a simple task.

The Power Filter section offers a choice of lowpass, bandpass, and highpass filters and a button that switches from a 12- to 24 dB slope. Along with cutoff frequency and resonance faders are controls for Width, which fine-tunes the filter's slope; Drive, for adding grit; and a Gain fader, for adjusting the filter's output.

To conserve CPU cycles, use the Master filter. Setting its Tone slider before the center notch engages a 2-pole lowpass filter, which becomes a highpass filter when moved right of center. AHDR envelope generators offer independent control of Amp, Filter, and Pitch. You can adjust each envelope's Velocity modulation and envelope depth. Small blue lights indicate when LFO- or envelope-depth parameters are active — clicking on them inverts the modulation value. At the far right, a button reverses loop playback, and a slider changes sample start time. Changing the sample start time affects individual slices and radically alters their timbres (see Web Clip 1).

To simplify editing, an Easy button pares the Edit page down to four faders, two knobs, and two switches, with Level and Pan faders on the right and the Master Filter's tone control and emphasis fader on the left. The left-hand knob controls pitch, and moving the switch to the right changes the knob's resolution to fine tuning in one-cent increments. To its right, another knob controls the Amp envelope, and its switch toggles decay and release parameters.

Controlled Chaos

The plug-in's centerpiece is Chaos Designer, which uses probability to affect loop variations (see Fig. 3). In nearly every instance, Chaos Designer produced surprising and useful results. Using it with Edit Groups, wherein you can select which loop regions should be altered and which remain unchanged, was particularly effective.

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FIG. 3: Chaos Designer uses probability to animate loops in numerous ways. You can add probability to pitch, dynamics, placement in a groove, and more.

Chaos Designer's Pattern feature controls the probability of slices being moved to different locations in the groove. Small amounts of that parameter produce tasteful results, leaving the groove uninterrupted except for occasional variations. Full-bore Chaos applied to the Pattern parameter can turn simple grooves into busy Tower of Power-style syncopations. Reshuffling worked especially well with arpeggiator patterns, rhythm-guitar loops, and other melodic motifs (see Web Clip 2). The Repeat function controls the likelihood that a variation will recur, and Reverse regulates the chance that a slice will play in reverse. Because changes in the sound's envelope may not always suit the groove, Reverse works best in small doses. If needed, you can tweak reversed samples using the Edit page's Sample Start parameter.

The Timing section controls the probability that a slice will enter early or late and adds even more flexibility with its two knobs. Rush/Drag increases the chances that a hit will rush or drag, and Range governs the amount. Using those controls, you can change a groove's feel from rushed and edgy to relaxed or downright sloppy. To further alter the feel of a groove, you can edit its associated MIDI file within your host.

The Pitch section sports a slider for probability, a knob for the likelihood of upward or downward pitch change, and another knob to set the range of allowable pitches. Narrow settings effectively simulate the natural pitch changes that occur in drums and percussion. With probability and range set high, Pitch creates wonderfully twisted grooves, especially with cymbals and hand percussion. Note that Chaos parameters for pitch trigger discrete pitches as opposed to continuous Pitch Bend effects.

You can weigh the chances that an Edit Group will play louder or softer with the Dynamics fader — a knob to its right skews the odds in either direction. Finally, the Range knob compresses or expands the amount of modulation. At its loudest, the settings are conservative and protective of your speakers and tympanic membranes. At the low-amplitude end, slices can duck into silence, creating rhythmically interesting space in otherwise relentless grooves.

If you like what Chaos Designer is doing, click on the Capture button at the conclusion of the number of bars you want to retain, and you'll generate a new MIDI file that you can drag directly to a host track. Then, disable the Master playback and Chaos buttons, and the track will trigger RMX exactly as recorded. If you want to preserve the groove's MIDI data for use elsewhere, use Export to save it as a Standard MIDI File.

Most Effective

RMX's FX page supplies a rack of three insert effects for each of the eight parts (see Fig. 4). In addition, the eight parts can share four racks of auxiliary effects and a Master rack of effects, all of which offer three effects per rack.

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FIG. 4: The Insert rack is one of the many racks of effects in Stylus RMX. Four Aux racks and a Master rack each hold three effects. You can assign different effects for each Edit Group in the Insert effects and place effects in any order.

Dynamics processors include compressors, limiters, a tape-saturation simulator, and an expander/gate. EQs are graphic and parametric and offer a couple of vintage models. The filter-based effects offer a wah-wah that is controllable with an envelope follower or a synchronizable LFO, a multimode version of the Power Filter, and a valve-radio simulator. There are four delays, including the Radio Delay, which combines independent left and right delays, a multimode filter, and a defeatable feedback loop. Other effects are an analog tape-echo simulator, a pair of phase shifters, a flanger, distortion, and three reverbs (including spring).

Version 1.2 adds several new processors. The update supports presets, which can have single FX or FX racks, and a nice assortment of factory patches are supplied with the installer. Effects are high quality, with buttery-sounding filters and smooth reverb tails.

Mixing It Up

On the Mix page, you'll find all eight parts arranged vertically and controls for level, pan, and auxiliary effects-sends. The vertical orientation may briefly confuse those accustomed to a horizontal array, but it reinforces the concept of layering loops, and the controls are easy to grasp. At the top of the page are buttons for switching between Multi and Kit modes, and other controls let you mute or solo parts and assign them to your host's available outputs.

You can use RMX in Multi mode to pepper grooves with any of the thousands of single-instrument hits, but Kit mode changes RMX to a full-bore, eight-part drum-kit sound module. Drum kits adhere to General MIDI applications, but don't let that dampen your enthusiasm: the sounds are a diverse bag, encompassing roughly 10,000 single-instrument hits imbued with compression, filtering, vinyl simulation, distortion, and other processing. You can audition and exchange similar kit components in real time, without a hiccup in the groove. Kits can receive data on MIDI Channel 1 or 10, or you can play each Element over channels 1 through 8, keeping each on its own data stream. All of the FX- and Edit-page parameters can impact Kit components, and components also respond to the Chaos Designer's Reverse, Dynamics, and Pitch functions.

Grooves at Work

Stylus RMX offers two modes for working with the MIDI files that control a groove: Slice Menu and Groove Menu. In Slice Menu mode, the MIDI file triggers each of the slices that comprise the groove in sequence. That allows the slices to be quantized, reordered, or otherwise manipulated directly in the host.

In Groove Menu mode, a single MIDI note triggers an entire groove. That mode facilitates polyphonic layering of loops and lets you start with a simple pattern, then change the groove's intensity by adding or subtracting loops while controlling Velocity.

Adjusting the plug-in's parameters from an external controller is easy: select MIDI Learn from the Utility menu, twiddle a hardware knob, move an RMX parameter, and it's under external control. (RMX lets you assign independent positive and negative modulation to the same knob or slider.) When I experimented with this feature, RMX responded smoothly, producing no zipper effects or discontinuities in the groove. Modulating Chaos parameters in real time produced sonic variations ranging from subtle to over the top.

Like other loop-oriented plug-ins, Stylus RMX locks to your host's tempo but doesn't respond to MIDI Start, Stop, Continue, or Song Pointer messages. Expanded System Real-Time capabilities would provide a powerful bridge between the plug-in's unique, on-the-fly editing features and the general stop-and-go nature of sequencing. Version 1.2 partially alleviates that limitation by adding MIDI Learn functionality to the Master Start and Stop buttons. That offers the added benefit of letting you start and stop playback at any point in a song.

SAGE Advice

RMX's documentation consists of an installation guide and the tutorial CD-ROM. Registered users can access a PDF index of the video-tutorial topics, host-specific instructions, supplementary QuickTime tutorials, an FAQ section, and links to User groups from the Spectrasonics Web site. The QuickTime tutorials are a terrific illustrative resource, but there are gaps. Spectrasonics claims that a built-in reference guide will be available by the time you read this.

It will be a long time before you exhaust the Core Library's possibilities. In case you do, or if you wish to add more acoustic-sounding loops, Spectrasonics bundles the SAGE Converter, a miniapplication that can quickly adapt REX, REX2, and RCY files to SAGE format. In conjunction with Propellerhead Recycle, any sample is fair game, effectively making the Stylus RMX library open ended. The application can also convert some Akai and Roland Groove Control libraries. Most often, the conversion worked beautifully, although occasionally some sounds would play back with a stutter or unnaturally truncated slices. In every instance, that was the fault of poorly prepared third-party REX files (garbage in, garbage out).

Stylus RMX is a terrific multifaceted tool for sculpting unique grooves and brings a hefty quotient of fun and ease to the process. Chaos Designer in conjunction with the built-in effects, Edit Groups, and an uncomplicated MIDI control setup, bring extraordinary depths of animation and precision (see Web Clip 3). The elegantly designed user interface greatly simplifies potentially complex tasks.

Without a doubt, Stylus users should move up to RMX for $99. I also enthusiastically suggest that anyone else interested in groove construction give Stylus RMX a long, serious look.

Marty Cutler teaches MIDI classes at Touro College in New York City, and freelances as a sound designer, MIDI consultant, and bluegrass banjo player.


Although my preference is for more traditional, acoustic-sounding loops (I'm not fond of overly distorted percussion or vinyl noise), the RMX grooves won me over. In most cases, the feels are interesting enough to override my concerns about the processing. Quite often, distorted loops blend in gracefully when integrated into some of the Multis.

A few of my favorite loops include Datalife Combo, which comprises traditional drum-kit and percussion sounds passed through a battery of filter, chorus, and other modulation-delay effects. Perilous Vocal Slicer uses processed voices and can demonstrate Chaos Designer's effect on melodic content. Valium Vinyl is a Multi that combines a couple of full-kit loops with congas and rhythmic noises into a relaxed, shuffling juggernaut. Ritualistic artfully combines a couple of hip-hop loops with a sustained, percussive drone and a rhythmic figure played on berimbau.

Notwithstanding some great hand-percussion elements, there are few natural and unprocessed-sounding loops in the Stylus RMX core library. Fortunately, Spectrasonics is supporting RMX with a series of SAGE Xpander sound libraries ($99 each).

I auditioned four titles: BackBeat, Liquid Grooves, Metamorphosis, and Retro Funk. A fifth collection, Burning Grooves, should be available by the time you read this. Ilio announced the release of several RMX-ready Sage Xpander collections: Stark Raving Beats, Ethno Techno, Skippy's Big Bad Beats, and Skippy's Noizebox.

BackBeat grooves have noticeable degrees of ambience, EQ, reverb, and dynamics processing and a focus on rock and pop; many loops, however, also work for funk, fusion, or smooth jazz. One-shot samples of cymbals and side sticks help to punctuate grooves and add interest. Despite its title, Retro Funk covers a multitude of genres. The focus is on acoustic drum kits that emphasize a vintage analog sound. The set adds a good selection of hand-percussion loops, including congas, bongos, shakers, and tambourines. BackBeat and Retro Funk are ideally suited for RMX Groove Menu song-construction techniques. Each Suite lays out basic grooves, fill bars, and isolated fills that you can lay end-to-end for a complete song form.

Drum kits mingle with Korg Wavedrum, slit drums, tablas, congas, and other ethnic percussion in Liquid Grooves, a globe-spanning collection suitable for film scoring, world music, and anything else that can benefit from an eclectic flavor. The set favors a layering approach with full mixes, remixes, and individual-instrument loops that you can add or subtract to vary the rhythmic intensity.

Metamorphosis throws in the kitchen sink with drum kits, synthesis from hardware and software sources, drum machines, ethnic percussion, and more. Extensively processed grooves create unique sounds and rhythms suitable for remixes, space funk, ambient music, film scoring, and the adventurous at heart in general. The Suites and Elements are gathered by bpm, with completely different elements under one Suite rather than the song-construction arrays of the previous three sound sets.

All four of those products combine their loops into rich, complex Multi presets that integrate Elements from the Core library and a bonus set of grooves culled from other titles, including Bizarre Guitar, Distorted Reality, and Vocal Planet.


Stylus RMX 1.2.1real-time groove module $299


PROS: Extremely intuitive user interface. Chaos Designer creates musical, animated content from static loops. Great-sounding effects with flexible routing. Edit Groups let you customize synthesis, Chaos, and effects for every slice. All edits are available during playback.

CONS: No owner's manual.