What is an effects loop and how does it work?
If you’ve been playing for as long as you can remember, using myriad amplifiers and pedals in your rig, then you’re probably pretty up to date with how each pedal interacts with each other and how to get the “best pedal order” to keep your tone sounding good.
However, even though you’ve been playing for a while and definitely know your way around a guitar and your gear, you’ve likely looked at the back of your amp and shuddered at the thought of trying to figure out what those extra jacks are for, especially the ones labelled ‘Send’ and ‘Return’ above/underneath the ‘FX Loop’ like I have. “What does it do? If I plug something in will it blow up? What is an effects loop?” – these are all questions you ask yourself from behind the couch in fear – well I know I did!
I know I’ve looked at the back of the amp and thought “Nope, not gonna try that out today” but alas, the time is now and today we’re going to figure out exactly what an effects/FX loop is, how an effects loop works and how to use an effects loop! Some people love using them whilst others never use them regardless of how many pedals they have – so let’s look at the finer details together and you can see if using one might be the best for your sound.
What is an effects loop?
I’m glad you asked. An effects loop is an input/output that allows you to place effects between the pre-amp section of the guitar – where it gets its tone and the power section of the amplifier – where it amplifies the sound. This means that your pre-amp can go anywhere in the signal chain rather than having to be the last stop.
It’s also used best when you’re using the gain channel or cranking your amp into distortion and you want to preserve the amp sound before modulation gets a hold of it. When you run modulation, delay or reverb straight into the front of your amplifier, this affects the pre-amp (or tone of the amp) and some guitarists sense that this sometimes makes them sound muddy.
For example, if you play distorted riffs on a guitar in a vast cave you get tonnes of reverb bouncing back at you, which can sound great. However, if you were to take that reverb and put it through the amplifier, the amp would compress the sound (as it’s supposed to do) and thus lose all of the gorgeous intricacies of the cave, leaving you with an affected signal. This, of course, is something you might like, but not every guitarist wants that sound.
Why would I need an effects loop?
You don’t actually need an effects loop on your amp as plenty of guitarists don’t bother using them, especially if you’re only using distortion, fuzz or boost pedals. But if you want to get far greater clarity when using effects like modulation, delay and reverb, the effects loop might be something you’ll appreciate.
Up to the late ’70s, amplifiers did not feature an effects loop as you essentially got more gain by turning the amplifier up as loud as possible. However, since the invention of the gain channel in the 80s as an added feature and its use to get an overdrive tone, guitarists have often placed modulation effects after the amplifier has been overdriven to get a clearer sound.
When you place the effect before the pre-amp you colour the tone, whereas when placing the effect after the pre-amp, you are getting all the richness of your tone and the pedals use that rather than dictating what’s going on. If you’re using rack-mounted effects, this can also help reduce any loss of signal. Which brings me to my next point…
What does an effects loop do?
When delay, reverb, or modulation goes in front of or before the amp (or pre-amp) it can sometimes make the effect seem dull. If you’re using a delay, you might find that effect ends up becoming less effective and the tone changes towards the end of the repeats. An effects loop basically keeps the overdrive of the amp intact.
It’s worth noting, that if you are only using your amp as a clean signal and getting all of your crunch from distortion pedals, you’ll probably not really need to use the effects loop, and you’ll get a really good sound just by placing everything in front of the amp i.e. Guitar > Pedals > Amplifier.
How do I set up an effects loop?
If you have an effects loop in the back of your amp, you’ll see two jack sockets named ‘Send’ & ‘Return’ and they usually look like the image below.
To set up your pedals in the correct order, take a look at the diagram below, as this is the recommended way to set it up. You’ll need 2 extra guitar leads to do this.
As you can see the drive, distortion and fuzz pedals are before the pre-amp as you want them to affect the sound, whereas the EQ, modulation, delay and reverb pedals are set after the pre-amp as you want to take the tone of the pre-amp and hear that correctly without colouring it. Again, it’s worth mentioning that this is purely the recommended way of setting them up, but you might find that a different method works better for you.
Take a boost pedal for example – if you place it before the amp, it will only drive the pre-amp, but place it in the effects loop before it hits the power amp and it will likely boost the whole signal making the overall volume louder, which is exactly what you need to make those solos stand out! There is definitely no correct or ‘One Size Fits All’ method, so it all comes down to personal taste.
Hopefully, this little guide has given you an insight into how the effects loop works. Experiment with it and sculpt the sound you want – no need to hide behind the couch anymore!
Get in touch
Take a look at a full range of great guitar amplifiers and effects pedals at the Dawsons Website. Alternatively, pop into your nearest Dawsons store where our instore specialists will be happy to help you out.
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Lee Glynn is a guitarist and multi-instrumentalist who lives in Liverpool, England. After moving to the UK from Perth, Australia, Lee enjoyed a successful career as guitarist in Liverpool based rock band Sound of Guns.
After releasing two albums, a myriad of EPs / singles and touring extensively around the world for 6 years including stops at Glastonbury, Latitude Festival, as well as the coveted Reading & Leeds Festivals, Lee decided it was a time for a change of scenery.
Utilising his experience in music journalism, Lee now works within the web team at Dawsons Music, where he can still relay his passion for music by producing great content for the Dawsons blog and social media. Lee is still an avid guitar player and writer.