The Science and Magic Behind Variax Emulations
Variax® technology is often misunderstood. One of the reasons that it is so effective at recreating the sounds of other instruments lies in the fact that it is NOT a MIDI guitar. MIDI guitars trigger a series of samples or impulses based upon the data output of a special “hex” pickup. Because the pickup is only spitting out data, the age, size, and type of string used doesn’t really matter much. The strings can be completely dead, and yet the sound never changes because the sample being triggered hasn’t changed.
If you think about this relative to a modern MIDI keyboard – where the sound of the grand piano never changes even if the keys are broken or dirty – it should make sense.
The Variax, on the other hand, is recreating the sound of other instruments by altering the real sound of the piezo pickups embedded in the bridge.
The type of pickup used, and its location is critical to the sound of a Variax. A piezo pickup works by translating vibration from the string (which is transmitted by the pressure of the string itself) into sound, and it is more effective at picking up high frequencies than a magnetic pickup is. Also, the closer to the bridge string saddle a pickup is located allows it to “hear” more high frequencies.
This should make sense to electric players, as the neck pickup always sounds “warmer” than a bridge pickup does, due to the physics of how a string behaves.
So, the fact that we use a piezo pickup located in the bridge string saddle on Variax means that we are able to pick up the most accurate high-frequency response possible. Incidentally, this setup is one of the reasons why Variax technology does such a great job at emulating acoustic guitars.
So we’ve established that we’re altering the output of the piezo pickup to create the Variax instruments available on the guitars. Due to the fact that we’re playing around with the real sound of the strings through a pickup, that brings up a couple of different points: it means that the guitar will sound dead with dead strings on it, and it also means that the size of the strings matter just like it does on any other instrument. In short, it’s still a guitar.
Not only that, it means that we have to take the sound of the host guitar into consideration as well. A string doesn’t vibrate in a vacuum. All of the attributes of the guitar come through the pickups: string size and type, body type, body size, body wood, metal bits, etc. All of these things contribute to the sound of the guitar.
Based upon that information, here’s a little-known fact: we’re not really creating models of other instruments. What we’re really doing is creating an offset between the sound of the vintage “source” instrument, and the sound of the real Variax guitar itself!
The process to accurately recreate a different instrument via Variax technology is quite involved. We capture the sound and resonance of the body itself, of the strings and string types, of the pickups, of the magnetic pickup pattern that is unique to each pickup type, the strings own decay and resonance, and the sound and values of the actual wiring and pots in the guitar.
It is a highly involved process, and it takes a long time. We take the Variax’s own sound into account, and using filtering and resonators, shape it to behave like the source instrument through its pickups. Even nuances like flatwound strings can be heard and felt when playing the archtop instruments, which is a testament to the accuracy of the modeling technology.
In truth, that accuracy can be revealing, as some of these instruments are over sixty years old. At that age electrical and wooden parts can begin to change their behavior, and that can wreak havoc on the modeling process. Let’s just say that it takes a lot of patience to model a guitar made in the 50’s!
At the end of the process, the outcome is a Variax model that is highly accurate to the original. When you record the output of both and compare them, it is extremely difficult to tell the difference, and that is one reason why Variax technology is in use in studios and on stages around the world – it’s one real guitar that sounds like a host of other real guitars.