Introduction: DIY Chewie Monsta (Ed Sheeran) Loop Pedal

Mobius Pedal for under £150

If you read through this and think its a bit too much work leave me a comment, I'm going to make some of the bits/complete pedals up (with a revised design and some proper PCBs etc) and putting a few on ebay if enough people want them.

This is not a full guide but more of a 'what I did'. I think it will take a bit more research to build it if you have o experience in electronics or scripting but the Arduino and Mobius forums are full of answers if you need them, or just leave me a comment.

Being a massive Ed Sheeran fan and a live performer in an acoustic duo I have been into loop stations and live looping for quite a while. After watching Ed performing his plus album live I decided that I needed to get a loop pedal for my own live performances. At the time he was still using the RC-20 but I decided that having 2 separate tracks would be better for what I wanted so I went out and bought an RC-30. I have used the RC-30 with the FS-5U for quite a while now both for recording and live performances and I have to say it is great. It really helps to add in extra dynamics to our performances and helps to liven things up in a pub gig.

After a while I decided that 2 tracks wasn’t enough and changing between each track can be a bit distracting as no matter how confident I got I still had to look and check I was on the right track before I stopped or played it. I spend a fair amount of time designing and building things anyway (it’s also part of my job) so my obvious next thought was ‘can I make one…’

I spent a lot of time researching and decided that to get decent latency and a good enough sound quality for recording and gigging probably wasn’t going to be possible without a massive time and money
investment. I had a look at the RC-300 but it’s a bit too expensive for me considering I would only use a few of its
features. So I decided to leave the idea and just carry on with my RC-30.

Then Ed release the multiply album and along with it came the Chewie Monsta. As soon as I saw it I wanted one so I started doing some research. It turns out that it is basically a MIDI controller that controls a software called Mobius running as a VSTwith Ableton as the host. This allows multiple inputs and outputs but best of all Mobius is totally customisable. WOW I could make one of these!! After a load of searching it turns out nobody had really come up with a way to make something like this. A few people have made similar things but they all wanted to include other bits in that I didn’t need. I also wanted to space out the pedals more like Eds.

So I spent A LOT of time watching as many videos of him using the pedal to try and work out what it was doing. This is what I came up with.

The board has 9 buttons:










Fairly simple I thought but watching him use it didn’t seem to make sense. I assumed the arm track buttons where just arming the track and then you would have to press Record/Play to start them but this wasn’t
happening. So I guessed that the Mode button switches from Record to Play. When you press the Track1, Track2
etc this is Record/Overdub/Play in record mode and Play/Stop in play mode. Watching a load of videos again
this seemed to make sense to what Ed was doing and seemed to make the whole loop pedal a lot easier to use. So I decided to go with that and got to work and here’s how I did my version of this pedal. See a video of it in action here:

One thing to mention is that this is not an exact copy there are a couple of things that I have noticed are different in the working of the pedal. These are:

When Ed starts the first recording I think he records onto all channels but with the input level on all but the first channel turned down (I think this is done a lot which ever tracks are not being used to record have
the input level at 0). This will automatically give him 4 loops of exactly the same length synced up in one go.
I haven’t done this as I didn’t see the need. I like to see that if I haven’t recorded to a track it is still empty.

When all tracks are stopped the Track1, Track2 buttons become arm buttons so he can stop all and then select say 3 tracks and bring them all back in together. Again I only wanted 3 tracks so I didn’t see the need for this for me.

NEXT: What you’ll need (leave out anything you don’t want. This is what I used for mine):

Step 1: Gather the Bits...


Arduino IDE Software (

Mobius 2.5 ( - FREE Nice to give them a donation though because this is the key to the whole thing).

DAW (if you want to host Mobius as a VST)


Audio Interface (I use
not around anymore but as long as it has enough inputs and a MIDI In it will

MIDI Cable 3m (£3.99)

VGA Cable 3m (£5.28)


For the Pedal

(You could use an off the shelf MIDI controller like Behringer FCB1010)

Buttons (I used M-AUDIO SP-1 sustain pedals
£10 each)

Screen (
- £24.19)


MDF Sealer £5

MDF Primer £5

Spray Paint £7.50

ATmega328 (with UNO bootloader & Arduino if you don’t already have one) -

PerfBoard £0.78

1kOhm Resistor £0.63 (for 100!!)

LED £0.14

LED Bezel £0.37

7805 Voltage Regulator £0.37

100uF Capacitor £0.08

16mHz Crystal £0.21

22pF Capacitor £0.02

2.1mm DC Jack socket £0.62

9V 2A Power Supply with 2.1mm DC jack plug £9.85

VGA Socket ( - £3.83)

180 Degree 5 Pin Din Socket - £0.35

Total Cost of Mine was: £142

Step 2: Make the Enclosure

Obviously do what you want here. Make it work for you, how you want your buttons to be. This is the point of building your own, you can have it just how you want it. Here's some info on what I did.

Here is the plan I drew up for the controller enclosure. I’m not going to go into too much detail there are plenty of good woodworking/finishing tutorials out there.

I painted mine in black and made up some labels. I wanted something custom so I added a bit of decoupage for fun!!

To fix in the pedals I used self adhesive Velcro so I can replace them in future if needed.

Step 3: Making the Electronics

Here’s a schematic of my pedal electrics. If you want to build this yourself I suggest
you look at
which shows how to setup an Arduino on a bread board. If there is enough interest I will make a
load of these up on a PCB with ¼” Jack connectors (or screw terminals) so the
pedals can be connected without any soldering, and stick them on ebay.

You could do this in many ways and if you want to use an Arduino but don't want to do the soldering you could get an Arduino Nano, Arduino micro, Arduino Uno, teensy or any other Arduino IDE compatible device. Download the pde and upload it to your board/chip (lots of guides on this depending what you use) and wire up each pedal, the LED, the MIDI Socket, a VGA connector and a power socket.

Step 4: Mobius

Mobius is a really great VST and makes this whole thing possible. All the scripts are here to download (some of these still have in some bits that aren't needed as I've been through a few revisions but they work fine). Just attach each script to each pedal. To do this have a look at the pics. Put the pedal into Record Mode (LED on) press Global Capture in Mobius, select the script and press the button followed by New. Repeat that for each button in Record mode. Then press Mode to change to play mode (LED off) and repeat.

Onto Mobius

I suggest you start with stand alone Mobius just to test your pedal all works. Have a look through the documentation (
as it is much more detailed and very interesting to see the capabilities of Mobius. They also have a great forum
here The scripts are in the download folder. Unzip it and put it somewhere
you will remember.

To select the scripts and get them working with the pedal have a look through the images.

Have a play and see how it all works for you.

If you want to setup Mobius as a VST have a look at the forums or do some searching as it’s different for every DAW.

Any questions leave a comment and I’ll get back to you.

Have fun!!

Step 5: And Some Final Pictures.