Headload™ Development

For over 20 years, the Radial engineering team has been looking at guitar attenuators and trying to figure out what makes one better than another. We've listened to how various competitor products sound and examined what features are actually needed when it comes to controlling the sound levels that come out of a guitar amp and deliver the signal to the PA system. Truth is, there is no substitute to driving a speaker cabinet hard and playing with a hurricane of sound pressure from a double 4x12 stack. It is without a doubt one of the most euphoric moments a guitarist can ever experience. The problem is that the rest of the world frowns upon us as we blow away the PA system with our personal wall of sound. So we figured that the time had come to create a viable solution.

Radial President, Peter Janis, shares his perspective: "When I was playing on stage, I had three amplifiers: a Kustom 250 head with a 1-12 EV cab for clean rhythm, an early 60s Fender Super Amp for Hendrix or Zep type solo tones and a 100 watt Hiwatt for the prerequisite wall of sound. The Hiwatt was too loud and the Fender not loud enough. But back in the 1970's we had very little tools to choose from. A few years later, I remember hearing that Alex Lifeson with Rush liked a particular type of load box that had a light bulb in it. I bought it and was completely underwhelmed. It did not sound like my amp... it sounded mushy and compressed. We then heard of a company that built a load box using the guts from a speaker including the magnetic assembly, voice coil and spider – without the actual sound producing paper cone. Again, we were left disappointed – it sounded just like a resistive network. At the end of the day, we found that most load boxes ended up sounding very similar.

"This got us thinking... the sound from the amplifier is made up of more than the distortion from the amp: it comes from the resonance of the speaker cabinet and the actual air it moves when driven hard. In other words, there is no substitute for the real thing.

"The Headload does not try to resolve the inherent problems by making false claims. Instead it addresses the problems associated with performing live and in the studio by delivering a unique solution. And this solution comes not merely via the resistive load that it employs, but in how it handles the signal after the load has been applied. The Radial JDX is the cornerstone of the design. The JDX is a direct box that connects between the head and cabinet to deliver both the sound of the head and the back-electromagnetic impulse from the loudspeaker. The signal is then passed through a series of carefully designed filters that emulate the sound of a Shure SM57 in front of a 4x12 Marshall cabinet. Today, the JDX is used by all kinds of artists that represent a tremendous diversity of musical styles. This includes Megadeth, Dimu Borgir, Evanescence, Sting, Rascal Flatts, Steve Vai, and a host of others."

So why does this matter? Artists do not merely listen to their guitar amps on stage. In fact, more often than not, they are listening to wedge monitors or in-ear monitors. The amp is merely reinforcing the guitar or simply there for show. By delivering a great, consistent tone to the monitors, the musician performs with confidence. And because the direct feed is always consistent, there are no surprises caused by the varying acoustics in the room or weird resonance from a hollow stage. The Headload's JDX circuit adds a few extras that are not on the original: it is equipped with a 6-position selector switch that lets the artist choose between several cabinet types to suit his needs. This is supplemented with a high and low shelving EQ to fine tune the sound or take the edge off overly bright amps.

Janis continues: "One day, while on the System of a Down stage, I noticed how the sound guys combined a JDX with a Phazer for each amp so that the tech could listen through his in-ears while he adjusted the phase between the guitar amp's microphone and the direct feed from the JDX. We figured that adding a Radial Phazer inside the Headload would be beneficial. With a Phazer, you can create huge over-the-top tones or dial in cool out-of-phase Boston tones by simply changing the phase relationship between the mic and JDX direct feed. It is absolutely addictive and will be a huge benefit for studios that track guitars. We then decided to take things a bit further by adding a 6-position voicing switch. The idea here is simple: when simulating various guitar amps and cabinets, it is not a one-size fits-all situation. This is particularly true in the studio where developing unique tones is important. The Voicing switch lets you experiment with various pre-set curves to find the one that is best. This is supplemented with a 2-band EQ to further tailor the sound to suit."