I bought the Line 6 Firehawk FX, it's a multi-effects pedal which also has amp-modelling in it. So it can process the signal as if it runs through many pedals and then some well-known amp.

Then, in the output, there are 2 modes I can choose. One is AMP mode which send the signal strength as an instrument level, to appropriately connect to a real amp.

Another is LINE mode which suitable for connecting to PA, as the signal strength is going to be sent in line level.

My question is: Which route should I go?

I'm still questioning if I go with the first route, will it be that I double the amp process? because the signal will run through both modelling amp in the multi-effects pedal and the real amp in the end of the chain. And that way if I choose to use some famous amp in the multi-effects pedal, the sound might not be as it should be when run through my poor amp in the end.

  • 1
    Does (can) the AMP mode disable all of the amp and speaker models in the effects unit?
    – Dave
    Jan 25, 2018 at 14:07

4 Answers 4


It depends, really. If you decide to connect it to the input your amp, you do want to disable the amp modelling in the pedal (assuming that's possible).

I can think of three ways to hook this up. I'll list each way and reasons why you would choose it:

Connected to the PA

You should consider connecting directly to the PA if:

  • You don't have a very good amp.
  • The PA includes good stage monitors or an in-ear monitoring system.
  • You trust the engineer who will mix the show will do at least a decent job.
  • You have a PA you can practice with along with your band to be able to practice show levels.
  • You want to take advange of the different amp models in the pedal.
  • You need to keep stage volume very low (houses of worship, cruise liners, corporate gigs, some weddings, and other gigs not primarily rock concerts are typical situations like this).

Connected to the input of your amp

Consider this connection if:

  • You have an amp you like, that you know well, and that you're used to playing through.
  • You mainly want to use the effects available in the pedal and not the amp models.
  • You play in a variety of situations where you don't know what kind of PA will be available.
  • You practice at gig level with your band without running your guitar sound through a PA, and you want gig sound to be as close to practice sound as possible.
  • You use feedback as part of your sound (it's harder, but possible, to use stage monitors for feedback).

Connected to the effects loop return of your amp

This is a bit of a hybrid between the other two options. It's almost like using the power stage of your guitar amp as a mini-PA just for guitars. Try this if:

  • Some of the points under "Connected to the input..." apply to you, but you want to use the different amp models.
  • You can enable the amp models in the pedal and also disable the speaker simulation in the pedal.

On that last point, if you can't disable the speaker simulation then you're likely to get a pretty poor sound if you run through an amp, since you'll have speaker sound on top of speaker sound which can get very honky.

And one more idea: You could pick up a decent keyboard amp and use that as a mini-PA, so enable the amp modelling and speaker simulation and then use the keyboard amp on stage the way you would use a guitar amp. A keyboard amp is more full-range than a guitar amp, so it is more like a mini mono PA for just one instrument.


I agree with all the other quality information offered on this subject.

I will add a few personal bits of advice, and this, based upon hard experience. These are not opinions, just facts:

  • A guitar effects processor produces an output signal that lends itself to connecting directly to a PA system, without using a guitar amplifier as a middle man.

  • Doing this will save your back (guitar amplifiers can be quite heavy), and it saves you having to mic your amp to the PA in the first place. It really simplifies your load-in and load-out from a gig.

  • You will be wise, as others have advised, to sound check this option thoroughly. Some guitar effects processors, particularly in the distorted voice effects, have a gritty, crumbly 'falling off' after a long, sustained chord or note, instead of a sweet and gentle signal fade. In that event, a guitar amp can actually help to sustain certain notes and chords slightly longer by virtue of their own sonic qualities.

  • Bring lots of extra batteries, to back up the AC Adapter. Just in case. (Most guitar effects processors have a battery back up feature.)

That is all.


The only way that you can truly tell is to hook it up and check it out and decide which one you like the best. Experiment with it a little bit and see what you can come up with you might find something off the wall that you like.


Yes, connect it directly to the PA with (and this is the most important bit) a Direct (DI) box - specifically a good DI box meant for the job. I put my Boss GT-001 to my mixer (Allen Heath Zed12 FX) with a Palmer PDI-09 Di Box. It's a great little DI that is purpose built for the task ad even includes a switch with warm and bright functions to help you wrangle your sound. Speakers are a small passive array by Thomann called the Box Pro. I play single act shows with guitar, vocals and backing tracks.

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