Review: Boss SY-300

Guitar synthesis goes back to the future
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It wouldn’t be the first time conventional wisdom has been turned on its ear in the audio world, but no one expected guitar synthesis to toss off the shackles of divided pickups and those fragile and expensive proprietary cables. The Boss SY-300 makes guitar synthesis about as close to plug-and- play as you can get: Simply plug in a standard 1/4-inch guitar cable and you are treated to synth sounds that follow the nuances and articulations in your playing (see Figure 1).

Although designed as a floor unit, the well-made SY-300 is equally at home on the desktop. The liquid crystal display is easy to read, and the four solid- feeling footswitches light up when engaged. The footswitches are raised and angled above the control surface, keeping the bottom of your shoe away from the programming area and display.

Alongside the output-level control are buttons for Synth/FX, Blender, and Write. Synth/FX brings up a schematic of the patch’s signal flow: You navigate and alter patch parameters using the four contextual knobs below the display and the Select knob on the right. The Select knob also serves as a push-button for entering and confirming a parameter or submenu. Below that are left and right Page buttons for navigating through groups of parameters.

Fig. 2. In addition to standard guitar input, the SY-300 provides an effects loop, Main and Sub stereo outputs, MIDI In and Out/Thru, and a USB port. However, the unit does not do pitch-to-MIDI conversion. For analog I/O, ¼-inch jacks are used throughout (see Figure 2). The Input accommodates guitar, bass, or anything else that can feed a strong enough signal. The Thru and Return jacks allow you to insert any additional processors into the signal path. (You can adjust the return level and phase from the SY-300’s System menu.)

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Stereo pairs of jacks are provided for the Main and Sub outputs, with the left Main jack doubling as a headphone out: I would have preferred a separate headphone jack, but given the I/O real estate, it’s a reasonable compromise. MIDI In and Out ports are provided, with MIDI Out doubling as a soft Thru. The ports are used for transferring System Exclusive, MIDI Clock, Control-Change messages, and patch changes.

If you need more control than the onboard footswitches provide, a rear-panel ¼-inch jack accommodates an expression pedal or a Roland-compatible footswitch. The USB 2.0 port connects to your computer in order to send and receive audio and shuttle patch data between the SY-300 and the editor-librarian (covered below).



The SY-300 extracts a polyphonic signal from a monophonic input in a manner similar to the technology found in polyphonic tuners, which isolate the dominant frequencies of an audio signal. But the SY-300 is the first of its kind to deploy Roland’s next-generation version of Composite Object Sound Modeling (COSM) to restructure the guitar signal into a workable model of a three-oscillator analog-subtractive synth. The result is that the instrument tracks immediately and flawlessly—with no perceptible delay.

As an analog synth, the SY-300 is relatively simple, but it provides enough bells and whistles to customize sounds to taste. Each of the three oscillators gives you a choice of using standard analog-oscillator waveforms, as well as a detuned saw-tooth, noise, and an audio input. Parameters vary based on the oscillator. For instance, choosing the audio input as an oscillator source disables pitch, sync, ring modulation, and other parameters, but provides filter settings, and limited LFO and amp controls. Amp and filter envelope settings are simple, providing only attack stages, as the signal lasts as long as the string is vibrating or audio input is sustained, although you can program one of the footswitches as a sostenuto switch.

Each oscillator gets its own LFO with a choice of the standard analog-style waveforms, including random and sample-and-hold. One nice touch is the ability to control the depth of the LFO using picking dynamics.

The SY300’s sequencer is limited, but each oscillator’s sequencer can be linked or run independently, allowing you to created interesting polyrhythms. The Step Sequencer gives you control over the depth of each oscillator, but provides no dynamic control or duration for individual notes. The control-assignment options are surprisingly rich, providing plenty of real-time flexibility via the footswitches as well as the ability to adjust the depth of the envelope. Increasing the noise waveform’s Sharpness parameter makes the sound more harmonic, with the maximum setting producing an analog-synth-style choir.



Many of the presets reflect old-school guitar synth tones: bright, buzzy leads; distorted, growling basses; and effects designed to accompany your guitar’s sound. Unfortunately, many of the preset tones drip with too much reverb and distortion, and some simply sound like overly processed guitar.

The good news is that the instrument is easily programmable. Boss facilitates the process with its free Tone Studio editor-librarian software, which lays out all of the parameters to keep you from deep front-panel menu diving. (See the sidebar “The Tone Studio Editor-Librarian”.) I was able to coax a reasonable take on Roland JX-10-style horns easily, along with a few good leads and pads. Tone Studio is also a gateway to a free, online library of additional sounds. Although the sonic landscape provided by the SY-300 is considerably better than what the factory sounds present, you are restricted to its analog-modeling synth architecture; there are no realistic pianos, organs, horns, or drum kits.

It’s also important to remember that the SY-300 is not a MIDI converter. The SY-300 undeniably tracks more accurately than the best MIDI guitars, although the absence of pitch-to-MIDI conversion is a mixed blessing. Freedom from the typical encumbrances of a MIDI guitar (proprietary pickups and cables to connect external synths, and associated issues such as ensuring compatible pitch-bend settings and configuring the synth’s proper modes) are all refreshingly absent with the SY-300. However, the SY-300 does not provide the means to record MIDI note data into sequencers, or access to the external world of synthesizers at all.


Nonetheless, the SY-300 is considerably more than a guitar synth or MIDI guitar converter: Any audio material you can feed the unit through the ¼-inch input or the USB port is fair game for resynthesis through the instrument’s oscillators, including vocals or audio tracks from your DAW (a task that no MIDI guitar converter can accomplish).

Furthermore, the SY-300 doubles as a guitar processor, and each oscillator can serve as a different signal chain. The supply of effects is reasonably broad, offering delay, reverb, filtering, chorus, flange, and rotary effects, among other processors. The SY-300 also serves as a 24-bit, 44.1kHz audio interface, albeit one with a mono analog input.

As a player’s synth, the SY-300 excels. The typical bugaboos that haunt the guitarist—slow, inaccurate tracking and excessive cabling—are nonexistent with this device. Its easy computer connectivity via USB and the editor-librarian make programming your own sounds a breeze, while its modest dimensions allow the processor to sit on the floor or your desktop. Overall, the Boss SY-300 is a pleasure to use, whether onstage or in the studio.


The Tone Studio Editor-Librarian

Fig. 3. The free Tone Studio editor-librarian simplifies the process of creating your own patches. Tone Studio (figure 3) is a free editor-librarian for the SY-300 (available at that greatly simplifies the process of creating your own patches. Click on the Tone Central button (located at the bottom left), and you’re transported to the Boss Tone Central site, where you can download additional patches.

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Tone Studio receives and stores your current patch data. When launched, the editor opens to the patch currently loaded into memory, with a mockup of the SY-300 architecture in view. Click on any section of the header to focus on that parameter and its related pages. In most cases you can edit parameters with a knob or a pulldown menu, with values illustrated on a vertical bar graph. Any changes you make are immediately reflected in the SY-300, so it is easy to tweak while playing.

Other useful amenities include a tuner, an audio file player, the ability to set input sensitivity, and the System menu, which, among other things, lets you check firmware versions, edit global EQ for the outputs, alter MIDI settings, and edit patch maps.


No tracking issues. Accepts standard 1/4-inch plug. Easy to program. Can process incoming audio via analog or USB input.


Factory sounds are mediocre.

$699 street

Marty Cutler is hard at work on his book about digital guitar applications. Stay tuned.