Interested in guitar controllers but not in a mess of cables and converters? Casio's latest may be the answer: a synth built into a guitar.

SINCE THE INTRODUCTION of the keyboard synthesiser in the early 70s, guitar and keyboard technologies have evolved in very different directions. The electronic keyboard family has grown from amplified mechanical keyboards and electronic organs to include analogue and digital synthesisers, and the current breed of hybrid and sampling instruments. The evolution of the electric guitar, on the other hand, hasn't been nearly as dramatic. The state of the art electric guitar in the late '80s is basically a refinement of the old Fender Stratocaster, with modest improvements in electronics, materials, and machining.

Essentially, the keyboard has evolved into a family of sophisticated electronic instruments, while the electric guitar has not, and there has been little or no attempt to integrate more sophisticated electronics into the instrument itself. Surprisingly, the advent of the MIDI standard didn't do much to close the gap between guitar and keyboard technologies either. However, it did allow the guitar to serve as a MIDI controller for a sound module or external synthesiser. To date, guitar MIDI controllers have been plagued with tracking problems, due largely to the inherent slowness of pitch-to-voltage conversion at low frequencies (at least two cycles of a note must typically be sampled before that pitch can be identified).

The Casio PG380 Guitar Synth is the first (with all due respect to the Vox Guitorgan) serious attempt to go beyond the guitar MIDI controller, and into the realm of the self-contained guitar synthesiser. The onboard synth allows a guitarist to simply plug in and play, without the usual rack-mount array or pedal matrix. This really opens up the concept of the guitar synthesiser for the working guitarist - one who might play rock and social club gigs on the same instrument, as opposed to a studio musician who can (sometimes) take the time to get just the right sound.

Luthier Talk

THE GUITAR ITSELF is a Strat copy with two single-coil pickups and a bridge pickup that can be switched from humbucking to single coil operation. The maple fingerboard and ebony neck are well crafted, and the guitar is quite easy to play. The overall quality of the instrument is much higher than its predecessor (the MG510 Synth Controller). A Floyd Rose tremolo allows deep bends without loss of tuning. This tremolo has the drawback that to change strings it requires an Allen key (included) and a pair of wire cutters (not included, but necessary for cutting the ball end of the strings before seating them in the bridge). It is disappointing that Casio didn't follow Ibanez's lead and allow the tremolo arm to change the pitch (or whatever else was desired) digitally.

Another aspect of the PG380, that may take some getting used to, is the close proximity of the volume controls and hexaphonic synth trigger pickup to the bridge. The trigger pickup is right next to the bridge, and the guitar volume control is just in front of the trigger. If you're used to playing close to the bridge, things get very crowded, because there's really no room to rest your hand. However, these are relatively minor (and highly subjective) points, as overall the PG380 is an excellent guitar.

A built-in tuner stays in operation whenever the synth electronics are switched on (these don't have to be on for use in normal guitar mode). The chromatic tuner consists of two LEDs which indicate sharp or flat strings. When both LEDs are on, the string is in tune. I was able to tune quickly and accurately with this, and once in tune, the guitar stays there for a long time (the review model came out of the box in perfect tune).

Fugitive Electronics

THE BACK OF the guitar is partitioned into compartments for batteries, microswitches, trigger pickup sensitivity controls, and the ROM/RAM card slot. The electronics are powered by six 1.5V AA batteries or an optional AC adaptor. The battery compartment is covered by a plastic plate that is held in place by two screws. These screws can be turned with a coin, but for a quick battery change, the arrangement is somewhat awkward. Also, the hinged plastic cover of the ROM/RAM card slot tended to pop open from time to time on the unit I tested.

A set of batteries kept the setup powered up for around 12 hours, with no problem. When the batteries begin to weaken, the LED display will flash for 15 minutes and then the power automatically cuts off (an analogue battery condition indicator would be nice, to prevent the guitarist from being caught in the middle of a set of music with dead batteries).

"Tracking: The real test of any guitar controller or synthesiser is its tracking - to put it simply, the PG380 tracks better than anything else I've tried."

The pickup sensitivity controls and microswitches are easily accessed by removing rubber covers from the compartments. The sensitivity controls allow the synth trigger pickup to be adjusted for each string. A sensitivity check mode is initiated by turning the power on while simultaneously pressing the octave up and down keys on the front panel. In this mode, the front panel LEDs display a number which indicates the relative trigger sensitivity when a given string is plucked. According to the manual, numbers below 85 indicate that sensitivity should be increased, while numbers above 99 register as "oL" (over level), indicating that sensitivity should be decreased. The adjustments are made by turning one of six set screws with a Phillips screwdriver. The process is pretty straightforward, and you probably won't want to change this once you've found the settings that match your technique.

The aforementioned DIP microswitches allow you to set the MIDI bend range, channel, and mode (poly/mono), as well as the exact pitch of the A of the built-in tuner (four settings are available, from 440-443Hz). There are eight bend range settings, ranging from 2-48 semitones. With the "chromatic" front panel setting enabled, the bend range is automatically set to zero.

Two standard ¼" output jacks are available on the PG380, which allow four possible combinations of guitar and synth sounds. The iPD/mix output yields a monophonic mix of the straight guitar and synth sounds, with the mix determined by the guitar and synth volume controls. The guitar output gives either straight, mono guitar, or both guitar and synth simultaneously (if a stereo plug and lead are used). By using both output jacks, separate mono iPD and guitar output signals are obtained. I found the guitar output to be significantly louder than the iPD/mix output, but was able to get a satisfactory mix using only one standard guitar lead.

The 64 preset synthesiser voices available on the PG380 are selected by entering the number of the desired voice onto an eight-button keyboard. The current voice number is displayed on a two-digit LED which is mounted at an angle, allowing a clear view from the player's perspective. The data keyboard arrangement takes some getting used to if you want to change voices quickly. One inherent problem with a self-contained guitar synthesiser is that a guitarist doesn't usually have a free hand to make adjustments, the way a keyboard player might, which is why many previous systems have relied on foot pedals for control. After some practice, I was able to make voice changes reasonably quickly. Additional pushbuttons allow voices to be shifted up or down one octave, and also select smooth or quantised treatment of string bends. There is also a front panel pushbutton to select optional RAM/ROM cards if any are installed (none were available in time for this review).

iPD Synthesis

THE 64 PRESET voices on the PG380 are generated by a new technology Casio call interactive phase distortion (iPD), which is also the basis of the new VZ1 keyboard synthesiser (reviewed elsewhere in this issue).

With iPD technology, it appears Casio are trying to provide the best of all worlds. Eight modules, each consisting of a digitally-controlled oscillator (DCO) and amplifier (DCA), generate independent waveforms which can be used to modulate outputs from other modules, or go directly to the audio outputs. These modules are set up in four pairs called Internal Lines. The waveform pair generated in each line may either be mixed or used to modulate one another for ring or phase modulation. An External Phase modulation mode allows the output from one line to modulate a module in another line.

"Sounds: If you hold a synth note - which is a natural thing to do with an organ or cello sound - it's disconcerting to have it cut off abruptly after 1.5 seconds or so."

The importance of understanding any of this depends on whether you intend to buy a VZ1 along with your PG380 so that you can program your own sounds on the VZ1, and then transfer them to the guitar via RAM cards. Without a VZ1, you have 64 preset voices and virtually no capacity to alter them.

Fortunately, the quality of the preset voices is quite good. Several of the piano and organ voices are outstanding, as are the flute, vibes, marimba, and steel drum sounds. Some of the sounds (the basses in particular) are more interesting when the octave keys are used to shift them out of their usual range. A few of the piano sounds tend to glitch during fast passages, and there are several novelty sounds (explosions and ambulances) which will be of little use to most players. These are not serious problems, but if you have 64 voices and no means of altering them, it would be nice if they were all winners.

Tracking and Slaves

THE REAL TEST of any guitar controller or synthesiser is its tracking. This is one area in which the Casio is quite surprising. To put it simply, it tracks better than anything else I've tried. The reason for this isn't exactly clear. Casio's promotional literature claims that the PG380 will "track its own internal sounds with no MIDI delay". This is undoubtedly true, but MIDI delay is not the source of the tracking problems that have plagued just about every controller on the market to date. The tracking problems are a by-product of pitch-to-voltage conversion, and Casio have managed to keep them to a minimum. The tracking on the low E and A strings, although a bit slower than that of the higher strings, compares well other units on the market. It has become a more or less standard trick for guitarists using pitch-to-voltage MIDI controllers to replace their low E and A strings with lighter gauge strings tuned up an octave to improve tracking. This won't be necessary with the PG380.

To use the PG380 as a MIDI controller, all that is needed is a MIDI lead and an external synth or sound module. The onboard synth continues to operate when the PG380 is used as a controller, so it's easy to get an extremely rich, layered sound by combining the guitar and onboard synth sounds with an external MIDI-controlled sound source. The unit does track its internal sounds somewhat faster than it tracks an external sound source, supporting Casio's MIDI delay claim, but it's impressive either way.

The PG380 may be used in either Poly or Mono modes. In Poly mode, all six strings control the same MIDI voice, while in Mono mode, each string can be set to control a different source. A DIP switch on the back of the guitar is used to set the desired mode.

Program changes are sent by entering the appropriate number with the pushbuttons on the guitar. Unfortunately, the appropriate number is not the actual program change number. Because the guitar keypad has only eight pushbuttons, an alternative numbering system must be used to access all the numbers from 0-63. Thus to send MIDI program change 3, the number 14 would be entered on the keypad and displayed, or to send 13, 26 is entered. Got that? Furthermore, program change numbers 64-127 can only be sent if an optional ROM card is installed.

"Guitar synth: The PG380 is the first serious attempt to go beyond the guitar MIDI controller, and into the realm of the self-contained guitar synth."

Living Live

I HAD THE opportunity to road test the instrument on a number of gigs, and the results were definitely encouraging. It takes a while to get used to having a Hammond B3 or Rhodes sound at your fingertips, or playing convincing classical flute duets with a flute player, but many of the preset sounds are impressive. The synth tracking is accurate and the majority of the onboard sounds are glitch free.

One thing that did strike me as odd is the lack of sustain on any of the voices. If you hold a note - which is a natural thing to do with an organ or cello sound - it's quite disconcerting to have the sound cut off abruptly after 1.5 seconds or so. The problem is that when the amplitude of the string falls below a certain threshold, the synth's circuitry reacts as if it has received a note off command. Without some kind of external sustain pedal there seems to be no way around this problem because the threshold is not adjustable.

The lack of sustain will also pose a problem for rock players, as the guitar itself is a fairly "hot" Strat copy, set up for rock playing, yet the synth provides no sounds that sustain as well as the guitar. Hopefully, Casio will address this problem in future updates or accessories.

Verdict

THE COST OF the PG380 is deceptive. Its list price is £1299, which might sound steep at first. However, you don't have to buy anything else to use it, so there are no hidden costs. Compare this to some of the other MIDI controllers on the market, which require that you buy separate trigger pickup and pitch-to-MIDI converter units (not to mention the price of the sound source you wish to control, and a guitar to use as a controller), and consider the fact that the PG guitar is an excellent Strat copy, I'd say the Casio is actually a pretty good buy.

To summarise, the Casio PG380 is a unique instrument that affords guitarists the opportunity to create a wide variety of synthesised sounds without the use of outboard accessories. As a self-contained synthesiser it's versatile and easy to use. It is by no means an ideal instrument, but it's the first of its kind, and Casio are to be commended for its introduction.

Price £1299.

More from Casio, (Contact Details).