What is the 4 Cable Method?
The 4 cable method is a way to hook up a compact pedals, stompboxes or multi-effects units to an amp in a way that allows you to control which pedals or effects are placed before the pre-amp and which pedals or effects are placed after the pre-amp in the amp’s effects loop.
The Reason…. why use 4CM?
Certain effects sound very different when placed before overdrive/distortion, or after. These differences are most obvious with time-based effects like reverb and delay. To a lesser extent, this includes modulation effects like phaser, flanger and chorus. For example, even a simple volume boost effect can work very differently, depending on whether it is placed before or after overdrive!
Why? A natural by-product of amplifier distortion is compression. So, the higher the level of preamp gain (distortion) used, the more compression appears. This alone is not a problem. In fact, it is this very compression that creates the great sustain that a high-gain guitar amp can achieve. But, the problem is that this massive compression can negatively affect the use of some guitar effects. Delay and reverb pedals for example, essentially compress to unusable levels when plugged into the INPUT of a high-gain guitar amplifier.
This very problem appeared during the high-gain guitar amp revolution of the 1980s. In order to use delay and reverb effects in high-gain amps, guitarists needed to place their effects after the preamp distortion, but before the power amp. Behold, the effects loop was born!
Pros to the 4 Cable Method
- Better control of your tone and better quality
- Get the most out of every effect or pedal you own
- More flexibility
Cons to the 4 Cable Method
- Messy setup
- More cables
- More complicated
Equipment Required for the 4 Cable Method
Amp with an effects loop
The 4 Cable Method (4CM), is a term usually heard in guitar-related conversations. It describes a way to connect your guitar to your effects pedals and amplifier. You connect using both your amplifier’s Input and its Effects Loop at the same time.
The first thing you need is an amp that has an effects loop. If your amp doesn’t have an effects loop, then you cannot use the 4 cable method. Small practice amps generally don’t have effects loop while almost all larger amps will.
The ability to run guitar effects either into the Input of the amplifier, or within its Effect Loop (SEND / RETURN) circuit, gives you different tonal results. This includes a big difference in how time-based effects (such as reverbs and delays) interact with your amplifier’s overdrive channel.
To implement the 4 Cable Method, you’ll need the following:
- 4 quality guitar cables. If you’re using pedals, you’ll also need patch leads for connecting them to each other.
- An amplifier with an effects loop. The effects loop jacks are found on the back of the amp. Look for the SEND / RETURN circuit.
- Your effects pedals OR a compatible Multi-Effects processor. So, to connect a Multi-Effects processor using 4CM, it will need to have EXTERNAL LOOP capability. That is, it needs its own SEND / RETURN jacks in addition to the usual INPUT and OUTPUT.
- A guitar!
4CM for Compact Pedals:
- WHITE CABLE 1: Connects your guitar to the INPUT of the pedals you wish to use BEFORE the amplifier.
- WHITE CABLE 2: Connects from the output of the above pedals, into the amplifier’s INPUT jack.
- BLUE CABLE: Connects from the amplifier Effects Loop SEND, to the INPUT of the pedals you wish to place after the amplifier’s sound processing.
- GREEN CABLE: Connects from the OUTPUT of the above pedals to the amplifier’s RETURN jack – to be sent directly to the power amp and speaker, bypassing the EQ & gain Stages of the amp.
4CM for Multi-Effects Processors:
- RED CABLE 1: Connects your guitar to the INPUT of the Multi-Effects processor.
- GREEN CABLE 2: Connects from the Multi-Effects processor’s External Loop SEND, into the amplifier’s INPUT jack.
- BLUE CABLE 3: Connects from the amplifier’s Effects Loop SEND, to the Multi-Effects processor’s External Loop RETURN.
- PINK CABLE 4: Connects from the Multi-Effects Processor’s OUTPUT, to the amplifier’s RETURN jack – to be sent directly to the power amp and speaker.
Try different effects in different positions in the chain to hear differences in the way the effects are driven. The possibilities are virtually endless. Enjoy!