Get Wired: Four Cable Method

Before we get into the guts of Four Cable Method – what it is and what it can do for you and your tone – we need to have a little history lesson. Once upon a time, using effects was relatively simple. Your only real connection concern was “What happens if I accidentally plug my guitar into my fuzz pedal’s output instead of input?” But we guitarists are notorious for inflicting crippling bouts of G.A.S. (Gear Acquisition Syndrome) upon ourselves, and it wasn’t long before the stage floor became strewn with all sorts of effects boxes. And then guitarists had to learn to tap-dance to control the damn things. So multi-effect units came along which offered the ability to chain combinations of effects that could be accessed with a single tap of the foot.
For a while, this worked fine for most players. The rise of digital multi-effect units came at a time when players were happy to derive their whole sound from effects, plugged into the clean channel or effects loop return of an amp. This was especially true of commercial rock and pop, where 80s production techniques tended to favour more polite sounds than in previous decades. The neater sounds of digital distortion of the kind found in multi-effect units was seen as more than adequate to form the basis of your main sound. Then the 90s came along and players fell in love with the sound of a roaring tube amp again. Even digital multi effect units started incorporating tube preamps. Another 90s quirk was that players fell out of love with digital effects, and instead started amassing pedals. Lots of them. Meanwhile digital modelling technology got better and better, to the point where you could get some incredible results.
But many players still love their amp’s natural distortion. They want to use effects through their amp’s front end, and also maybe some delay, reverb, pitch shifting and what have you through the effects loop. Traditionally this meant a return to the dreaded tap-dance, because multi effects units were always somewhat restrained in their input and output options. Either you plugged your guitar into your effector and plugged that into your amp, or you plugged your effector into your amp’s effects loop. If you wanted to turn on a phaser and an overdrive through the front end at the same time as a delay, you had to hit preset switches on at least two devices (unless you had them all synced up via MIDI, but let’s face it, guitarists are still scared of MIDI).
And that takes us to Four Cable Method. Essentially this is a way of hooking up certain multi-effect units so that you can use your amp’s own preamp distortion while also running different effects through the amp’s front end and effects loop simultaneously. The way to achieve this is to place your preamp inside the effects loop of your multi-effects unit (and bypass the unit’s amp simulation section). Not all multi-effectors have this feature, but the fact that players discovered Four Cable Method at all is owed to the fact that a few daring companies started to incorporate this feature, and now that the word has spread, more and more companies are offering loops within their multi-effects. It’s fast becoming a standard feature.
So how do you do it? Let’s look at it in step form.
1: Plug your guitar into the input of your multi-effects unit.
2: Plug the effect loop output of your multi-effects unit into the guitar input of your amp.
3. Plug the effect loop output of your amp into the effect loop return of your multi-effects unit.
4. Plug the ‘regular’ output of your multi-effects unit into the effect loop return of your amp.

Almost every multi-effects unit with an effects loop feature also has the ability to move the loop around within your patches. This is where the power of Four Cable Method really becomes apparent. Say you want to create a patch with wah wah, delay and reverb, using your amp’s preamp distortion as your main sound. Simply create an effects chain in this order: wah – loop – delay – reverb. Let’s call the patch ‘Wah Lead.’

There are some other neat tricks you can perform with Four Cable Method. For example, pitch shift effects usually sound best through the amp’s effects loop, but if you’re using a pitch shift model to make a faux 12-string sound, it’ll work best through the amp’s front end because that’s more like what your amp would be presented with if you were using a real 12-string. And although phaser and flanger effects can sound spacey and futuristic in the effects loop, they take on a totally different, more organic character when placed before the preamp. If your multi-effects unit lets you move the loop around within patches, you can place your phaser wherever you like in the signal chain depending on how it suits the song. Most of the time you’ll want to use delay in the effects loop, but sometimes delay can sound pretty cool when it’s feeding a distorted circuit – the repeats gradually become cleaner as the amp is presented with progressively quieter repeats. If you have a song or a section that requires that sound, just program a patch that goes delay – amp and off you go.

Boss GT-8’s Effects Loop and Amp Control jacks

It’s definitely worth pointing out that some multi effects units such as the Boss GT-8 and GT-10 also include an ‘Amp Control’ jack, which you can use to change channels on your amp from your multi-effects unit. So we can further elaborate on our ‘Wah Lead’ patch by telling the unit to select the amp’s overdrive channel instead of its clean channel. Now let’s create a patch called ‘UniVibe Clean.’ Our effects chain will be Univibe – compressor – loop – reverb. If you have an Amp Control jack, program the multi-effects unit to select your amp’s clean channel, and you now have two totally different sounds using two totally different amp channels, but you’re still using your amp channels.
Now, not all amps and multi-effects units play nicely together straight out of the box when you use Four Cable Method. With some combinations you might need to select specific pieces of gear to eliminate hum, background noise or tone suck. In my rig I use a Boss GT-8 with a Marshall JCM2000 DSL-50 amp. In order to get the clearest tone, I use Planet Waves Custom Series Twisted Pair cables for the two connections originating in the amp’s effects loop. In twisted pair cables, the forward and return conductors are twisted together to cancel out electromagnetic interference from external sources; for instance. I also use a Behringer MicroHD HD400 2 Channel Hum Eliminator, which can be added to either of the twisted pair cables at either end (I prefer to place it on my pedalboard right by the GT-8’s output, the one that plugs into the Marshall’s effects return.

The Behringer MicroHD HD400 helps to zap any stray hum.

Additionally, my Marshall’s channel select foot switch jack also carries enough juice to power the LED in the Marshall’s foot switch. When using the Amp Control jack of my GT-8 I use a cord with the ground wire snipped and shielded at one end. If you don’t do this, you’ll get ridiculous amounts of ground hum.
Even if your multi effect unit doesn’t have an Amp Control jack, many are capable of controlling channel changes within patches via MIDI, and there are aftermarket MIDI interfaces such as the Amp Gizmo by RJM Music Technology which can be plugged in between your amp’s channel control jack/s and your multi effects unit to make them talk to each other. This unit (and its little brother, the Mini Amp Gizmo) can interface with pretty much any equipment that uses a footswitch jack or 1/4″ external switching jack.
Another important thing to take into account is, is your amp’s effects loop wired in series or parallel? If it’s in series, the entire sound flows through the loop. If it’s in parallel, your preamp’s sound will be split in two, with half going straight past the loop and the other half going through the effects placed in the loop (usually with an effects level mix knob to adjust the level). Although series loops are much more common, many professional players such as Steve Lukather and Eddie Van Halen prefer running time-based effects like delay and reverb in parallel (although they do this with multiple-amp rigs, dummy speaker loads, audiophile-grade mixers and the like). If you have a parallel effects loop, make sure to turn the original note of your delay off within your multi-effects unit, so the delay is only playing the repeats, rather than the original note plus the repeat. Otherwise you’ll get some weird phase cancellation issues when the straight signal (which bypasses the effects loop) and the parallel signal recombine. In fact, you can actually mimic this even with a series delay in most multi-effect units, because they usually have a mix parameter for their own inbuilt effects loops.
Boss GT-8
Boss GT-10
Line 6 POD HD400
Line 6 POD HD500
Line 6 M13
Zoom G9.2tt
TC Electronic G System
DigiTech RP1000
DigiTech iPB-10

Join the Conversation


  1. And is possible the FOUR CABLE METHOD-CAPABLE UNITS with the Boss GT-100 ?

    1. Yep, Boss GT-100 should be there. I’d also add the Line 6 M13 and its smaller cousins – but I’m not sure the list is meant to be exhaustive.

  2. I use a TC Electronic G-Major 2 effects processor – it has two relays built in for amp switching via 1/4″ plugs. I control the G-Major with a Behringer FCB-1010 midi foot controller. Does all the switching with one button.

    1. The POD X3 Live works with the four-wire method. I used it with my Blackstar HT-5 and some other pedals with good results. I currently use all pedals–no multi FX–but I still use a four-wire method of sorts–up front FX in the amp, then volume/delay/reverb/chorus/trem in the FX loop of the amp.

  3. been doin’ a version of this for YEARS! i even put most of my gain peds 1st out of the loop (series), followed by an isp deci-g string…

  4. you have left out Boss GT-6 which also has a loop, ‘amp control’ is not available though

  5. I also have Marshall Dsl 2000 and the humming problem with Boss Gt 8. What exactly do you do with the Amp Control cable to eliminate the noise? I’m totally ignorant when it comes to electronics…

    1. Each of the cables in the 4CM has a ground path, and at least one path for the audio signal to pass between the amp and the pedal.
      The Amp CTRL doesn’t pass audio signal. It merely opens a circuit or closes the circuit within the amp. The ground path from the Amp CTRL to Amp is redundant and will pick-up noise in several forms.
      By unscrewing the shield on ONE end of the Amp CTRL cable and snipping the ground, you prevent the noise from travelling through the ground path. It also helps eliminate RF which can ride this path like an antenna.
      Make sure you mark this cable so that you only use it for Amp Ctrl, as it will not pass audio signal elsewhere.

      1. Thanks Allen!, this is great info.
        I have that same Planet Waves wire in the picture from the article, but I can’t figure out how to take it apart. Any ideas?

  6. i got the GT-6 and dont have the amp control and a peavey valveking II 50watt combo

  7. I’ve been using this method for a few years now. I’m running a TC G-system into a Hughes & Kettner switchblade. Plus a few other pedals in the loops of the TC unit and a few more in front. I still do a little tap dancing even with midi switching, but, that’s because I run sound and play guitar and do vocals. Pedals for all of that too!

  8. I use this method with my pod X3 live and my Trace Elliot Speed Twin. By utilising the programmability of the Line 6 unit, you can also bypass the front end of your amp and just use the processor going direct to the fx return of your amp, in my case meaning I can use amp modelling distortion into the power amp valves of the Trace Elliot. Sounds amazing!

  9. But if i had an Marshall JVM 410c it´s the same some story, as if it was the Jcm 2000???

  10. I tried this once, but the volume of my guitar (Epi LPStandard with EMG 81-85s) kept fading in and out. Could my multi have a bad loop, or maybe my output setting is wrong? it’s going into a Marshall AVT50H.

  11. “When using the Amp Control jack of my GT-8 I use a cord with the ground wire snipped and shielded at one end.” – what does this mean? Thanks!!

  12. Hopefully this discussion still has some participants.
    Using the GT-8/Marshall combo, what should the FX Level button on the Marshall be set at? The Output of the GT-8 is 0db but the Send is -10dB. Using the loop normally, it would be a no-brainer because the Send would come in the back and the button would be -10dB, but the Output is actually coming in through the return, so the question is -10dB or +4dB?

Leave a comment


Your Cart