Aug '15

BOSS GT-100 Guitar Effects Pedal: How to Make the Connections to a Sound Reinforcement System

La versione in Italiano di questo articolo รจ disponibile qui: Collegare la Pedaliera BOSS GT-100 ad un Impianto Voci.


Photo credit: BOSS Corporation

The BOSS GT-100 Guitar Effects Pedal is the newest model amongst their floor guitar pedal board products, a compact, rugged and powerful unit that can provide an impressive amount of possibilities to shape the sound of your guitar.

This kind of high technology jewels have become popular between guitarists, but you must be aware that how you make the connections is crucial in order to obtain the best from their possibilities, and the correct choice depends on the usage that you want to do of them.

If you want to use them for live exhibitions there are two philosophies: connected to an amplifier, possibility treated in this post, or directly to a SRS (Sound Reinforcement System) / PA (Public Address) system; if you want to use them for sound recording there are again two philosophies: analogically through the classic output jacks or digitally via the USB port.

This article treats the connection of BOSS GT-100 multi effects pedal to a SRS / PA system (but as you will see ahead even to a stage monitor or a keyboard amplifier), and refers to the Version 2.0 update of the onboard firmware.

Inside the article there are some references to the GT-100 Owner’s manual that can be freely downloaded here.


A guitar effects pedal powerful and complex

The BOSS GT-100 Guitar Effects Pedal is the actual flagship of their floor guitar pedal board products.

It’s a powerful device, in my opinion incredibly powerful compared to its price, that relies on the latest BOSS COSM (Composite Object Sound Modeling) technology. Just to give you an idea, these are some facts and figures extracted from its Owner’s manual:

  • the Preamp effect provides 25 + 2 (*) emulated types plus a custom one
  • the overdrive/distortion effect provides 21 types of distortion plus a custom one
  • the FX-1/FX-2 units provide 31 + 5 (*) types of different effects
  • the Delay effect provides 10 types
  • the EZ tone interface assist you in creating your own tones quickly and intuitively
  • the Phrase Loop feature permits you to record and play loop performances
  • the Parallel chain function lets you create two independent chains of effects with the full freedom to arrange the effects in any order

(*) available with Ver. 2 on board firmware

just to mention a few. Not bad, uh? Yes, but all these power brings complexity, and despite BOSS has made an excellent job in organizing the Human Machine Interface thanks to the “two screens user interface“, the BOSS GT-100 is not easy to understand and manage. As a prove of this, if you are intentioned to purchase a GT-100, take a look to some music instruments equipments selling announcements in your zone/country: I am quite sure that you will find someone that has played a little bit with a new BOSS GT-100, has been discouraged by its complexity and now is selling it at a lower price affirming that “it’s not for me“. ๐Ÿ™‚

The Owner’s manual at pages 22 and 23 describes all the possible connections as shown in figure 1:


Figure 1 – Photo credit: BOSS Corporation


Why connect the BOSS GT-100 directly to a Sound Reinforcement System

There are two main reasons that motivate the direct connection of this guitar effects pedal to a SRS / PA system:

  • fully utilize the preamplifiers simulations that can provide
  • the practical advantages that there are for live exhibitions and tones creation


Fully utilize the preamplifiers simulations that can provide

The excellent preamplifiers simulations provided by COSM technology are one of the most powerful characteristics of BOSS GT-100 Guitar Effects Pedal. The wide set of diversified clean, overdriven and distorted tones that it can produce depends on them, and fully utilizing them you will have the freedom to change amplifier in every patch that you will create.

Selecting a patch of the unit you will be able to pass from a sound based on a Fender Twin Reverb amplifier to another based on a combo Mesa Boogie one, or stack Marshall, Hughes & Kettner, Soldano amplifiers, just to mention a few. Imagine by yourself the endless possibilities to explore the most diverse sonorities that you will have at your disposal.

All this is not fully appreciable using a real amplifier, like explaind in the post “How to connect the BOSS GT-100 guitar effects pedal to an amplifier” at paragraph “BOSS GT-100 as preamplifiers simulator and effects unit“.

In order to fully appreciate it you have to amplify the sound produced by BOSS GT-100 with equipments that have a linear frequency response, thus that amplify the sound with the maximum possible fidelity without adding any tonal contribution.

That is possible with a Sound Reinforcement / Public Address system, but as you will see ahead even with stage monitors and keyboards amplifiers, all equipments that have a flat frequency response.

You are in front of a change of mentality: to abandon the “old” way of playing guitar with an amplifier behind you and the few sounds that it can provide to embrace the freedom to have at your disposal the best sonorities of many of the amplifiers produced until today brought by the technological evolution of digital simulation techniques.

And in my opinion it is not much strong the objection of some guitarists that the real amplifiers produce a better sound. It is true, when you can pump up the right volume and when tubes are ok in case of tube amplifiers, but I challenge everybody to hear the difference from the modern simulated ones when you play with a band.


The practical advantages that there are for live exhibitions and tones creation

The direct connection of the BOSS GT-100 guitar effects pedal to a SRS / PA brings even the following practical advantages:

  • tone independence from the volume: amplifying the sound produced with a linear device it is like to amplify a keyboard or reproduce an audio source like an MP3 or CD. The sonority of the tone produced does not depend anymore from the reproduction volume, like it often happens using real amplifiers, especially if tube ones. That brings even more benefit in case you play in events that require low volumes, like for example in small venues, or playing entertainment music in restaurants, hotels or parties.
  • elimination of the microphone and its support for the amplifier: since we direct enter into the SRS / PA, it is not necessary anymore to have a microphone plus its support, two in case that you play stereo, to pick up the sound from the amplifier. Less stuff to carry with you and mount, less space occupied on the stage, elimination of the issues of correct placing of the microphone and of its regulation.
  • less equipments to carry with you and mount: the modern ( ๐Ÿ™‚ )  guitarist can go to play simply with a guitar, the effects pedal and a set of cables !!! I do like that, you do not have to carry with you anymore amplifier, microphone and support to pick up its sound. There is another benefit in case that you play in a band, because it is reduced the number of vehicles necessary to move to the events.
  • tones can be created with headphones: since that what is produced by the BOSS GT-100 will be amplified with the highest possible fidelity without any modification, your tones can be comfortably created with headphones. That means that you will be able to do it everywhere just connecting your guitar, the effects pedal and headphones, at any time and without disturbing anybody. How to create tones using headphones will be treated in a future post.



Connection of the BOSS GT-100 to a SRS / PA system, stage monitor or keyboard amplifier

As you have read above, the principle at the base is to amplify the sound produced by the BOSS GT-100 with equipments having a linear frequency response, and in addiction to Sound Reinforcement / Public Address systems there are other two devices in the music ambit with this characteristic:

  • stage monitors
  • keyboard amplifiers

how to realize the connection is extremely simple and does not change with the device used, and is illustrated into Figure 2:



Figure 2 – Photo credit: BOSS Corporation


You have just to connect a cable to the output L/MONO plus a second cable to the output R in case that you want to utilize the stereo mode.


If you want to connect the GT-100 to a Sound Reinforcement / Public Address system, you have to connect the cable/s to the system mixer, generally to the line inputs because the guitar effects pedal already produces a high signal level. Tone controls of the channel/s used must be regulated flat, otherwise you would modify the tonal content of the sound, and obviously no mixer effect must be applied to those channels. The only thing that must be regulated is the volume !!! ๐Ÿ™‚ Having not anymore an amplifier behind you, arise the exigence of listening to what you are playing, and I suggest to use a stage monitor, placed in front or behind you , connected to a monitor output of the mixer. It in addition to reproduce your sound will permit you to listen even to the other instruments and voices, and having a wider diffusion angle compared to guitar amplifiers cabinets will be possible to hear it well in a wider zone of the stage.

The connection to a stage monitor has sense when you want to be amplified autonomously like you did with the guitar amplifier. Such an exigence can arise playing at home, or in small ambients where maybe the SRS / PA system is little and used for the voices only or even absent, or playing in instrumental or choral ensembles, think for example at a Gospel choir. Using a stage monitor you have to connect the GT-100 directly to it and I imagine to play mono, but is even possible to play stereo using two of them. The stage monitor/s can be the same that you use on stage for your live exhibitions.

The connection to a keyboard amplifier is technically possible and equivalent to the previous solutions but I do not understand its sense unless you can not renounce to have an amplifier behind you, but believe me that a good stage monitor does the same better. Anyway even in this case you have to connect the GT-100 directly to it and I imagine to play mono, but is even possible to play stereo using two of them. Tone controls must be regulated flat and no amplifier effect must be applied.


Moreover please note that is possible to use even the connections shown in figure 3 if you want to use external additional effects:


Figure 3 – Photo credit: BOSS Corporation

In this case note that the insertion or not of the external effects into the patch effects chain(s) is programmable into the patches.


Finally do not forget that it’s extremely important that you take care of the OUTPUT SELECT settings, see page 24 of the Owner’s Manual at chapter “Specifying the Output Device (Output Select)“. For the connections described in this post the Output Select parameter must be set as LINE/PHONES

We underline that as written at page 9 of the Owner’s Manual in the “memo” box “the SP type parameter of the preamplifier unit of GT-100 is valid (read produces an effect) only if the Output Select setting is set to LINE/PHONES “. Than having set this value will enable the SP parameter that has an interesting effect because let you simulate the characteristics of different speakers (number of cones, their diameter, and so on), and the typology of the microphone that picks up its sound and its positioning.


Related articles

BOSS GT-100 Guitar Effects Pedal: How to Make the Connections to an Amplifier

BOSS GT-10 or BOSS GT-100? That is the Question


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BOSSยฎ, COSM™, Fender, Marshall, Mesa Boogie, Hughes & Kettner and Soldano are trademarks of their respective owners.


1 Comment »

1 Comment » to “BOSS GT-100 Guitar Effects Pedal: How to Make the Connections to a Sound Reinforcement System”

  1. Henry Says:

    This video presents some more related information:

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