Roland VG8

Paul White gets truly virtual with Roland's new physical modelling guitar product — and no, it's not a guitar synth!

Roland's Virtual Guitar was first announced in January at the American NAMM show, where it attracted a huge amount of interest, and earned itself a brief preview in March's SOS. We're all pretty much used to leading‑edge technology popping up in the keyboard sector, but aside from the odd partially‑successful guitar synth, all the guitarist has had to show for the last couple of decades of progress are programmable effects boxes and locking tremolo systems (which, from what I can see, mainly mean that you can't change a string unless you have a socket set!). The VG8 is designed to change all that, but it isn't a guitar synth and it isn't a multi‑effects box — so what exactly is it? To answer that question, we first have to ask what makes up an electric guitar sound.

Unlike the acoustic guitar which is, well, acoustic, the electric guitar's sound is a complex synthesis of many different elements and parameters. The sound starts life as a vibrating string, but the vibration is influenced by the way the guitar body and neck resonate, and even a solid body has a noticeable effect on the sound. Next, the sound is picked up by means of magnetic pickups, but these impart a different quality to the sound depending on the brand, whether the pickups are single‑coil or humbucking, and where they are positioned relative to the end of the string. If two or more pickups are used, the tonal and phase differences between the various pickup outputs combine in a complex way to produce a new sound.

Once the sound has left the guitar in the form of an electrical signal, it is subjected to further modification by the tone circuits and overdrive section of the amplifier into which it is plugged, and after that, the sound is again coloured by the type of speaker used, how many speakers are used, and the type of cabinets the speakers are mounted in. When the sound leaves the speakers, it interacts with room boundaries, which produce reverb or ambience, and in the studio, there are further differences introduced by the type of mic used to record the sound, and its position relative to the speaker cabinet. No wonder, then, that it's so difficult to duplicate a guitar sound that you've heard on record — there are so many variables, and that's even before the studio engineer starts to add EQ and more effects.

Virtually Speaking...

The idea behind the VG8 is to collect the raw vibrations from the guitar strings using a Roland GK2A split pickup (included in the VG8 package), then use DSP processing to emulate all the other links in the chain, right through to the recording microphone. This process is known by the catchy name of VGM or Virtual Guitar Modelling, and is based on a system developed by Roland known as COSM (Composite Object Sound Modelling). Using VGM, you can 'virtually' select the type of pickups to use, decide where on the virtual guitar body to put them, choose a type of virtual amp (or even emulate a virtual Boss effects pedal), and then pick from three types of virtual speaker cabinet. You can even pan individual strings.

Once you've done that, you can position a virtual mic at a virtual distance from your virtual speaker cab, and if the engineers back at Roland have got it right, you should end up with much the same sound as if all those individual elements had been the real thing rather than the creations of the DSP chip. In theory, you should be able to recreate the sound of just about any type of guitar plugged into any type of amp and speaker setup, and miked with any one of several mic setups. The VG8 also has a separate pitch shifter for each string, which enables it to imitate 12‑string guitars, basses, guitars with alternate tunings and so forth (for live use, the speaker and mic simulators can be switched out). On top of that, you have conventional chorus, delay and reverb effects. But that's not all.

The other metaphorical string to Roland's virtual bow is HRM or Harmonic Restructure Modelling, another facet of COSM. Again, this works on the original string vibrations of the guitar, but this time these are separated into their harmonic components, which are then used as building blocks to create new sounds. Because the harmonic content changes depending how you play the guitar, the sound responds in much the same way as a guitar would — but the sounds themselves can be very unlike a guitar, falling midway between a guitar and a conventional synth, and retaining characteristics of both. Various synth‑like processes help shape the sound, including resonant filters, modulation and pitch‑shifting.

Out Of The Box

There is of course a non‑virtual, physical reality to the VG8 — it's a tough‑looking steel pedal unit that looks not unlike the doorstep from a Stealth bomber. There are six pedals along the front for Patch, Bank and Group selection, and rest of the interface comprises the Value knob and a surprisingly small number of buttons huddled around the display, as if desperate for each other's company. I'm not sure about the wisdom of black buttons on a black background, but at least the legending is white! A 3‑digit LED display provides a highly visible readout of the current Patch and Bank, while a backlit LCD looks after all the clever graphical icon stuff (see the 'User‑Friendliness' box for more details) while you're editing, and displays the patch names and patch information during performance. As it stands, the VG8 holds 64 preset patches and has room for 64 user patches. Further patches may be stored on a RAM card.

To use the VG8, you must fit your guitar with the Roland GK2A pickup system or equivalent (some guitars from Godin, Fender and Ovation now come with them built‑in). The first thing to do with the system (after tuning up using the in‑built tuner, of course) is to set the string sensitivity, and this is carried out with the help of a dedicated display mode, which registers the energy level from each string as you pick. This setting up is important, as an incorrect setting may result in either undue noise or unwanted (as opposed to wanted) distortion.

The VG8 rear panel isn't particularly complicated, and you'll be glad to know that the mains lead goes directly to a socket — there are none of those nasty power supply thingies that are so impractical on stage. Less satisfactory is the fact that the mains socket isn't a standard IEC type, so if you lose your mains lead at a gig, you could be in trouble.

A multi‑pin socket accepts the lead from the GK2A pickup, and a separate output is provided for the regular guitar sound. A short lead connects the output of your guitar to the VG2A, allowing the ordinary guitar signal to be routed down the main multicore. This serves the dual role of doing away with the need for an extra cable, and allowing the original guitar and VG8 sounds to be switched or added using the selector switch on the GK2A. Two regular jacks (which may be used balanced or unbalanced) carry the stereo output from the VG8, though you can work in mono by plugging into just the left output. Two more jacks function as auxiliary inputs, allowing an external stereo signal to be
fed into the VG8. One application for these is to to use the regular guitar output to feed an external effects unit, then return the effects unit outputs to the VG8 via the two Aux inputs. A headphone output is provided for practice, and two further jacks allow an external pedal and external switch to be connected. The switch is used to change patch groups or to access the tuning mode, and the pedal may be assigned control a variety of functions in real‑time, such as level changes, pitch‑shifting, and so on. A RAM card slot takes a standard Roland memory card, enabling a further 64 user patches and one global setup to be stored.

There are just two MIDI sockets; MIDI In is used when controlling VG8 patches from an external source or receiving patch dump information, and MIDI Out sends patch change commands or patch dump information. No MIDI note data is output, because the VG8 isn't a synth, and doesn't have tone oscillators. When the product was first announced, there was some uncertainty as to whether a simple pitch‑to‑MIDI interface would also be included (probably along the lines of Roland's recent GI‑10 guitar synth), but it seems that no such provision has been included. Given that most of the hardware is already in place, this seems a little remiss.

The Sounds

And now the bit that really matters: the sounds. The VG8 is really two instruments in one, insofar as it uses VGM to recreate traditional (and some less traditional) electric guitar sounds, and HRM to create guitar/synth hybrid sounds (see the diagram on P.94). Many of the VGM preset sounds have thinly‑disguised patch names that leave you in no doubt as to what they are supposed to sound like. For example, there's 'Hey Joe', 'PurpHaze', 'D.Purple', 'OldBeck1', 'ALman LP' and '8MilesHi'. This tells us a lot, not least about the type of person who's done the programming. Most of these sounds are classic vintage rock, ranging from the early '70s to the present day, and what's more, most of them sound very much as you'd expect them to. Most of the classic rock sounds are extremely good, though I don't think they have quite the same 'feel' as the real thing. As any guitarist will tell you, the guitar itself feels different when you've got a singing amp on the end of it, but with the VG8, the player/instrument relationship doesn't seem to be quite so intimate. I think the best way to describe it is to say that what you get isn't an exact simulation of the real thing, but a very convincing caricature. In the context of a mix, the sounds work extremely well, and all the usual playing nuances are translated flawlessly, but the sound doesn't sing out in quite the way it does with a real amp. In fact, most of the conventional rock sounds are comparable in quality with what you'd get out of a good guitar processor such as a Zoom unit, although admittedly the difference with the VG8 is that you can change from a single‑coil guitar to a humbucking guitar, or even to a 12‑string or bass, all using the same physical guitar.

Where the sleight of hand starts to show is when you set up guitar sounds that move away from the conventional. For example, the 12‑string emulations sound great, but heard in isolation, you can hear that unmistakable sheen that digital pitch‑shifting invariably introduces. Similarly, some of the out‑of‑phase pickup settings require very powerful harmonic restructuring, and you can hear a hard, digital edge to the sound which isn't quite natural.

On the whole, though, the VRM side of the machine works well, and the range of electric guitar sounds you can get out of the VG8 is almost unbelievably wide — there's even an E‑Bow patch. I also very much like the hex distortion facility (see the 'Creating Guitar Sounds' box), and though it doesn't emulate anything that already exists, it's a very useful sound in its own right. Aside from the pitch‑shifting and radical EQ artifacts that are sometimes evident on more extreme settings, there's really no clue as to the fact that you're hearing a digital preamp.

To me, the main disappointment is the lack of any serious acoustic simulations. VGM seems to be the ideal technology to allow electric guitarists to switch to steel or nylon‑strung acoustic guitars, upright basses, or even other plucked instruments such as harps, mandolins or even Chapman Sticks. Maybe VGM hasn't been developed enough to do this convincingly, but it's an area I think Roland should give priority to exploring. After all, there are any number of good guitar multi‑effects preamps that can give you a good range of rock sounds, but none of them offers a palette of acoustic simulations.

Moving onto the HRM sounds, I found many of these tonally interesting, and all combined the character of the guitar with something vaguely synth‑like, but they didn't seem so well‑behaved as the VGM sounds. For example, innocent hammer‑ons were often accompanied by clicks or glitches, and even playing very carefully and cleanly, the VG8 threw up the odd unpredictable noise. I had noticed a few of these glitches when the instrument was being demo'd at NAMM, so I contacted Roland, who informed me that they were aware of this, and that a new software update had significantly improved the situation. Unfortunately, they were not in a position to get it to me before our deadline!

It also seemed to me that the harmonic content of some of the HRM algorithms wasn't too far removed from distortion or noise, which gave some patches the tendency to sound very 'fizzy', even when played gently. On balance, I think HRM is a great idea with vast potential, and some of the patches are quite wonderful, but in its present incarnation, I still feel it is only partly successful.

Conclusion

For the session player who wants to get just about any guitar sound from one guitar, the VG8 is in a category of its own, and its ability to mimic 12‑string guitars, electric basses and even sitars and banjos is most impressive. The general sound quality is the equal of the better preamps currently doing the rounds, but rather more flexible. The HRM side of the instrument is, I think, less well advanced, but then this is a new technology, and may well lead to greater things. The best aspect of HRM is that the sound still comes from the guitar string, so if you pick in a different place, damp the strings or hit harmonics, all of that comes over quite naturally. Some of the HRM algorithms sound ethereal and wonderful, while others are notably less enchanting!

I don't think that the VG8 replaces the real guitar and real amplifier in the same way that Rory Bremner doesn't replace all the people he impersonates, but in situations where you need a lot of tonal variety from one guitar and one box, it achieves a great deal of what it sets out to do. I have to confess that whatever its shortcomings, playing with the VG8 is a lot of fun, and I found it very hard to leave it alone!

Because this is not a synth, the output can't be recorded via MIDI, but I would imagine that the guitar player buying this unit might also be the type of person likely to have a casual interest in MIDI guitars, and if that's the case, it's a shame that a pitch‑to‑MIDI interface wasn't built in alongside the VG8 system.

On the one hand I must applaud Roland for taking yet another brave step to provide the guitarist with a new means of musical expression, but on the other, I feel the unit concentrates too much on rock guitar sounds — and there are plenty of preamps around that do great rock guitar sounds, even if they are less flexible than the VG8. It would have been different if acoustic emulations had been built in as well, but as it stands, the most significant, unique aspects of the VG8 are the hex‑distortion, the HRM sounds and the ability to mimic 12‑string guitars and bass guitars. The facility to use open tunings without retuning is also intriguing, and may well appeal to live players who don't want to be forever changing guitars, but if you don't need these features, you you may do better to wait a while until Roland's physical modelling guitar preamp, the GP100, comes on line.

A one‑line conclusion has to be that the VG8 is a very impressive unit, but it isn't quite perfect. But since when has any new technology got it all right first time around?