Author: Tharusha Kavishan

You may have noticed a theme, (that I myself didn’t notice till various manufacturers and friends at NAMM 2018 pointed it out to me) unifying my posts on social media, various forums and even this website lately:

The idea and desire to bring every bit of processing power, DSP, routing philosophy and switching functionality that we enjoy in the recording studio, to our onstage guitar setups.

These include:

• Your ultimate signal chain you’d use on a mix, without regard to processing power, latency, frequency range and dynamic range response of the playback equipment or other limiting factors
• Switching between these sounds with no gaps, dropouts, glitches, or delay
• Controlling the internal parameters of these sounds in an intuitive way (auto engagement of wah pedals as a glaring example)
• Having every dream rig you ever even imagined available at the touch of a footswitch
• Being able to have both a perfect monitoring sound onstage as well as your ideal sound projected to the audience from the PA system

THE BASICS

The very basics of this system would be your guitar, whatever system would be handling the inputs and outputs and the DSP involved (be it a computer or multiFX pedal or modeling amp or mobile device, even your phone!), some way to control it (likely a pedalboard), and the ways to amplify this for monitoring and get it out to the PA system

DESIGN PHILOSOPHY

Ideally, especially due to the inherent rule of Murphy’s law and the perceived and often justified unreliability of computer systems, I would like to have the simplest, most foolproof setup possible

My “One Wire iOS FRFR setup” article is a prime example

As wireless as possible would be nice, and I include power wires in this. If it can be battery powered by rechargables, so much the better

An example of one of the possible components would be my Wireless, Battery Powered FCB1010 article

Portability is another big factor. You don’t want to be THAT GUY that takes 20 minutes to set up and still sounds like crap. You don’t want to be that guy that every soundman puts on blast to his peers.

The Two Path Philosophy!

Central to this whole endeavour, is the Two Path Philosophy: In short, there will be an onstage monitoring path, in the role traditionally filled by the guitar amplifier, and a Front of House path, where your signal goes to the PA system. Depending on the actual hardware used, these two paths may need drastically different signals, for instance, a traditional guitar amplifier used for monitoring will want a signal without any speaker simulation on it, while the PA system will absolutely require a cabinet sound to be present. This is a HUGE consideration, and one that the Marketing Machine will ignore or lie about time and again.

If you are coming from an audio engineering background, you will doubtlessly be aware of the constant bombardment of snake oil salesmen, scammers and the nonstop attempt of the Marketing Machine to separate you from your money. I have to warn you, that the guitar world is even worse. Its a mix of the willfully ignorant and deliberately deceptive and finding real answers can be an exercise in tilting at windmills. Good luck, you have been warned.

THE COMPONENTS

Here are the basic components in some detail, some or most of these may or may not be combined into a single unit, so take this for what its worth

Guitar to Interface

This part could be as simple as a guitar cable to your interface. In my case, I usually have a wireless with the receiver velcro’d to my FRFR speaker, which also has electrical power, the interface and the DI velcro’d or hot glued to it.

Interface

The way to get your guitar signal into the DSP system. This will usually be a combination of analog to digital converters, digital to analog converters, some sort of interface topology for your computer or mobile device, like USB or Lightning, and hopefully some monitoring and control facilities, like output volume controls (don’t laugh, a lot of them don’t have this basic feature!).

If you are using a modeling combo or MultiFX pedalboard, this could also include the interface. Some of them also include the switching functionality. Some of them can also be used AS a computer/mobile device interface either instead of or even WITH the unit’s internal DSP. (Pod XT Live comes to mind, it has a MIDI controller built in for footswitching, a real ASIO interface over USB and a lot of internal DSP). Many of these devices have an interface for the computer over USB but their drivers and control software do not truly allow you to replace their internal chain (such as the Line 6 Firehawk and Line 6 Amplifi 150) sadly.

Standard 2 channel computer interfaces

In general (and this could change) most people will be looking at the standard 2 channel computer interface for this.

Considerations:

• The most often picked models will have a DI input of some sort to minimize the amount of gear you need to carry. Again dealing with portability, the simpler the better!
• This can seem small at this point, but can yield a big stick live, is whether or not the interface includes a hardware output volume knob
• Direct monitoring: manufacturers of crappy drivers make all sorts of a big deal about this function, but its useless in our case. Any interface under consideration MUST be able to defeat the direct monitoring function, we definitely don’t want (in almost any case), the unprocessed guitar signal running out the outputs in parallel with the processed signal
• Round Trip latency – This is usually the be all end all, though in real world testing, people are nowhere near as sensitive to reasonable latency as the Marketing Machine and forum trolls would have you believe. I made a Round Trip Latency chart with contributions from users around the world. This is a good resource to compare interfaces, and though it could be seen as a correlation/causation fallacy, I have found, almost without exception, that the faster drivers are more reliable and less resource hungry. Take that to the bank
• Connectivity – Eeek, due to the competing standards of the FRFR systems’ inputs, and the adaptability issues you can run into with anything aside from XLR, this can be sketchy. For the most part you are going to see 1/4″ females for the output of these interfaces, though some will have XLR (yay! assuming your FRFR has XLR inputs) or unfortunately RCA. Some will only have an output on a stereo 1/4″ meant as a headphone output. Also check just which outputs the previously mention output volume knob controls, it may not be the one you were hoping for
• Distortion – This can be another biggie. A lot of these interface choices absolutely cannot handle the output of hotter guitar pickups. Some distort in the analog realm, no matter where you set the input gain. Some go over 0dBFS even at the lowest gains, but do not appear to distort in the analog realm

Here are some specific USB interfaces that are commonly seen for our purposes:

Shown also are the Round Trip Latency numbers at 512, 256, 128 and 64 samples. Yes, some can go lower, but that’s largely academic. A lot of the DSP we will be using has an RT CPU processing time around 2 milliseconds so anything under that could be irrelevant. It all depends on what you are doing with the signal

The Top Tier:

These are the three with really low RTL figures, and generally highest regarded (rightly or wrongly)

RME has long set the standard when it comes to drivers and performance, regardless of how much the Marketing Machine would love to replace them. Usually RME and MOTU are going neck and neck, but unfortunately, MOTU’s USB performance seems to trail far, far behind.  This model has XLR outs, MIDI, onboard meters, and a nice fat volume knob, It also has a not so nice, big, fat, 750 dollar price

This model comes highly recommended across reputable sources, though I haven’t tried it personally. It has MIDI, 1/4″ outs on separate jacks, and a big, fat, obvious volume knob. $250

This device’s RTL numbers justify its inclusion to this particular category. I haven’t tried one myself, and the amount of hype surrounding this company, and what sure seems to be Marketing Machine saturation has made me highly skeptical, but the numbers look good. Separate 1/4″ output jacks and a nice, big volume knob. $200

Commonly used models:

The ubiquitous Focusrite units really dominate this market. Forever locked in a war with Presonus over this particular chunk of the userbase, Focusrite’s commitment to user support really seems to help tip the scales in their favor. You will likely be able to find Focusrite products wherever you go and there are always deals online for bundles with these products, in case you need to add recording studio considerations to your purchase as well as the guitar stuff we are focused on here. The 2i2 has separate 1/4″ outs, while the Solo has RCA’s. Both have a nice volume knob and a switch to defeat the direct monitoring. $150 for the 212, $100 for the Solo. Where these seem to fall behind is the RTL at 256 samples, they definitely hold their own at 128. Definitely worth adding to the Focusrite offerings here is the 2i4, which brings MIDI I/O and balanced line outs on separate 1/4″ to the table, at $180

Yep, Behringer. The drivers for these two in particular are actually pretty good! I warn you in the strongest terms not to assume the same for other Behringer drivers. Many require you to use ASIO4All instead. Both units have separate 1/4″ outs and volume knobs, with the 204 adding MIDI I/O. While at extreme low latency settings the focusrite drivers are ahead, at 256 samples, the Behringer drivers pull ahead. $60 dollars for the 202 and $80 dollars for the 204

There are tons and tons of other USB interfaces out there, and if one really screams out at me, I’ll be sure to list it

iOS interfaces

You might well want to read my guide to iOS interfaces for some detail

Sonoma Wireworks StudioJack Mini/GuitarJack Stage – These are the gold standard in iOS interfaces at the moment. HEALTHY output levels, pristine sound quality, stable drivers, lightning powered, with actual stereo outputs, and pass through charging. SJM has stereo outs on a single 1/4″ TRS, while the GJS has separate 1/4″ outs. Unlike most of the rest, these units can handle the Dual Path Philosophy on 1/4″, which can be a real life saver. GuitarJack Stage adds switching and realtime parameter control over MIDI to the equation, plus an expression pedal input. StudioJack Mini goes for $150 while GuitjarJack Stage can be found for $300. iOS has a lot lot lot of limitations for our purposes, the Sonoma Wireworks interfaces certainly help as much as they can to get around them. There are other interfaces out there for iOS, but these two come extremely highly recommended. ASIO drivers let these interfaces double as USB computer interfaces for Windows and OSX as well.

IK Multimedia iRig HD2 – These are probably going to be the most common interfaces you’ll see and come at a decent price. The 1/4″ output is mono, though it does have stereo outs on 1/8″. No ASIO drivers, though it does work with extremely long latency with ASIO4All. $100

DSP System

The “computer” used for processing. Play your guitar thru your interface, interface sends a signal to the computer, the computer modifies your sounds, send it back out through the interface into the speakers for you and your audience to hear.

MultiFX combos and MultiFX pedalboards fall in this category, but for the most part, they are too limited on their own for our purposes here. We’re really looking at two platforms at this time: Desktop/Laptops running Windows and OSX or tablets running iOS.

iOS

Although it could be argued that iOS was really first to the party, and that the saturation of iDevices on the market means that apps and hardware would be plentiful and well evolved, in reality the iOS system is far, far behind the laptop offerings. While there is AudioUnits, sort of, there is no VST, or VST type system to route, process and modify audio between applications. InterAppAudio and AudioBus do actually perform some of these functions, but not in as meaningful a way as you would probably expect at this stage in time. Audio apps are not really developed with real world, onstage use in mind, and their lack of market knowledge really shows in many painful ways.

All that said, you might still be perfectly happy with what’s available out there.

Newer iPad models are certainly powerful enough to handle the processing you want to do.

Sadly, though they were so early to the market, Amplitube for iOS is a pathetic shell of its VST or standalone laptop version. You may find Tonestack as a decent approximation though (and it comes with some cool tricks of its own). Bias and BiasFX work almost the same as their standalone laptop versions do (minus the painful exclusion of Impulse Response loaders, though they will load amps made on the laptop with impulses baked in), though these two processes really benefit from the help of other VSTs and DAW’s internal routing to really make a complete package. There are a few IR loaders you can run inside AudioBus or IAA, but I found them to be far too sketchy for reliable use.

Both Tonestack and BiasFX have workarounds, although very limited, that can get them to Two Path outputs. Tonestack has a splitter and you can put a speaker cabinet on one path, while the other path can carry a signal with no speaker cabinet. For BiasFX, you can create one Amp with an IR built in for the PA path and another amp with the cabinet bypassed for the guitar amp signal. Recent versions of BiasAmp 2 may have an issue with this, I’ll keep this updated. The Bias Solutions require that you have Bias Amp desktop installed on your laptop or desktop. All of the Two Path issues require that you have an interface with stereo outs in order to implement the solutions, so keep that in mind.

Tonestack brings auto engage for the wah to the table, and FX ranging from usable to full on VST quality. Bias seems to have the same quality of amps, indistinguishable between the iOS and VST.

MIDI implementation across the iOS apps is not exactly something to be jumping for joy over. Again this really feels like a case of the creators not having to use these things live onstage themselves. While certainly workable, for the most part, these fall far, far short of even a 1990’s multiFX pedal system, which is a sad indictment on humanity indeed.

Personally, my iOS setup has Tonestack as the host app with Bias FX run inside it through IAA, as I just can’t quite get the Tonestack amps to sound the way I’d like

Desktop/Laptop (Windows/OSX)

Edit Table

Switching System

Monitoring System

Front of House System

EXAMPLE SYSTEMS