When digital (or algorithmic) music processing first came onto the scene in the 80s, there was a fair amount of skepticism. Justifiable so, the processing power available at the time meant that complex algorithms were just not possible to execute in real time. However, pretty soon, algorithmic reverbs such as the Lexicon and Bricasti units became mainstays of modern studios, in fact digital recording tools in general gained wide acceptance within many music communities over time.
Guitarists though have been perhaps the largest group of hold outs. There are many reasons for this, for one, guitarists tend to be traditionalists. However, this is partly because guitar amps, in particular have been difficult to get right with algorithms. The distortion characteristics tend to be multistage, very sensitive to input volume and dynamics, not to mention the interaction between power output and speaker. Guitarists often complain that digital models just don’t “feel” right.
Algorithms have improved massively in the last 5 years or so and now there are many great options, in blind tests even the most ardent digital critics struggle to guess correctly above 50% whether they are playing a digital or real amp. Now with the rise of machine learning assisted signal chain captures, digital guitar tones are better than ever, this means that many guitarists are entering the “in the box” world for the very first time.
If this is your first foray into the world of digital guitar processing, there are a few terms that can be a little confusing. Namely, Amp Sims, Amp Models, and Amp Captures or Profiles. Unfortunately, these terms are not always used discretely. However, it’s often easy to tell the difference based on presentation.
An “Amp Sim” is typically a fully algorithmic representation of a piece of equipment. The behaviour of each important feature has been incorporated into the algorithm. The creators of the sim have attempted to make each knob and switch act just like the real amp would, whether it be gain, EQ, master volume, or any of the other features amps have. This means if you turn the presence up on a Dual Rectifier sim, it should react in the idiosyncratic way with the Treble and Middle EQ that you expect. Amp sims tend to allow you more control over your experience because they have all the same features the real equipment would have. Many guitarists entering the digital world like this because it’s familiar.
The word “model” or “modeler” is a little tricky to define, sometimes people are using the word interchangeably with sims, most often when it comes to digital floor units. But sometimes, they are referring to captures which I will talk about below. Typically, you can tell when it is a sim or a capture because the features of the “model”, or “modeler” will be different in presentation.
Captures are a somewhat recent development. They were first popularised with the Kemper Profiler. What they all have in common is that they feed a pre-defined signal through a piece of equipment, then use either an algorithm or machine learning to make any input respond the same way as if it were being run through the profiled/captured equipment. The upside of this approach is you tend to get a very accurate model of the entire chain, both dynamically and sonically. This is great for musicians who might for instance have a favourite amp -> cab -> microphone -> preamp combination that they would like to use live without having to take all that equipment out of the studio. The downside is that captures cannot be manipulated like the original equipment could. The settings are fixed and any adjustments made after the fact are unrelated to the original chain. A later article will explore why this limitation isn’t really a big deal.
When entering the digital world for the first time this is the trade off you will have to decide upon. Do you want the experience and tweak ability of amps the way you may already be familiar with them? Or do you want the sound and feel of the amp to be as close as we're currently able to recreate whilst giving up real tone stack tweaks etc?
A common complaint I hear from people moving into the digital world is that amp sims don’t recreate the “feel of being in the room”. This is a problematic assertion in some ways, mainly because amp sims, and captures for that matter, have never attempted to do this. Ostensibly, because it’s impossible. Amp sims seek to recreate what the amp itself sound like, compare the direct output of a real amp, either through a DI box, or load box, to amp sims or captures without cabinet simulation, they sound remarkably if not unidentifiably similar. The same can be said for the amp being connected to a speaker cab and captured with a microphone. Again, the result is, these days, unidentifiably similar.
The problem with the “in the room feel” argument is that you have to ask the question, which room? From which position in the room? At which volume? Saying an amp sim doesn’t feel like an amp in a room is like saying your pear doesn’t taste like an apple. Why would it? You’re asking something of amp sims they have never attempted to achieve. Having said that, amp sims and captures are so accurate now, with modern technology, that if you want that feeling, you merely need to hook up your sim or capture to a clean power amp through a real cab and you will get the full experience in the room. Obviously though, you will never get that experience through headphones or studio monitors, because in that scenario what you are simulating is a recorded tone.
The final thing I see many guitarists do when moving in the box is constraining themselves to thinking like guitarists. I see many people seeking only recreations of guitar gear in the digital realm, especially when it comes to things like guitar pedal effects. An important thing to think about when it comes to guitar pedals is that they must fit their circuitry into a small enclosure and be able to run off an 9v power supply. This is actually quite limiting and means in many cases guitar pedal versions of effects like compressors are compromised versions of what is available.
Once you move in the box you have an entire world of studio gear emulations available to you. You could look for a compressor pedal VST, sure, or instead why not explore an LA-2A, 1176, Fairchild etc? There’s an entire world of creative modulation effects, delays, stutter, granular synthesis etc. Not only this, but a large number of these things can be found for free by some talented and generous developers. When you start going in the box for your tones, it’s time to start thinking like a producer, and not just a guitarist.
There’s never been a better time in history to get creative with guitar using modern technology. The fact that things like NAM, and various plugin developers, offer amazing plugins for free means that almost anyone has a huge array of tones available to them. The democratisation of music is really exciting and I can’t wait to see what else develops in the next few years.