[SYNTH DIY] Custom Power Cables: Ribbons, Dupont, and XH
After a period of burnout after failing multiple times trying to build the erica synth edu snare drum–in which I just figured out today while trying to build the hihat module from the same set that my issue was that I was not using switched jacks (me not reading the manual properly)–I am back at it! I have built a few modules like Hagiwo’s drum sample module and this TomTom module; and they are mostly in working order. I also built 4 1/8inch to 1/4inch jack converters so I can stop using adapters when sending signal to my mixer.
But I am not going to be talking about noise makers today, instead we will look at another major source of frustration that I have overcome: my DIY power cables.
TLDR If you are DIYing power cables, you want to use JST XH cables for the most durable, readily available and cheapest solution.
Ribbon Cables
Ribbon cables are the standard when it comes to eurorack. I have tried researching why they are the standard and it seems that it is what Dieter Doepfer decided and there is no real reason behind it. Ribbon cables were abundant at the time, but were they more abundant than just regular wire? The cons of ribbon cables are obvious:
- They require a lot of material to manufacture them
- This results in a higher cost
- The are big and bulky.
- They only bend in one dimension.
- They are redundant (6 of the 10 pins are ground, 2 pins are +12v, 2 pins are -12v)
If I were to buy 10 12-inch eurorack ribbon cables it would cost around $25. If I ordered the same amount of materials to DIY them myself from tayda (where I get all my electronics stuff), it would cost $7.70 plus shipping. The shipping is expensive, but you are buying stuff anyway so let’s not factor it in. While the DIY price is not crazy, I think we can do better.
Dupont Cables
Dupont cables were the bane of my modular diy existence. They are cheap, flimsy, difficult to crimp, non-polarized. I have used them for a few years now and in most cases where something wasn’t working, it was because a cable fell out of the dupont header. I do not think one of my cables survived being plugged in more than 10 times.
The parts are definitely cheap though! you just need female headers, and you can use bare header pins for the male connection. And you obviously need stranded wire, but you should have plenty of this already.
You can get 50 power cables worth of dupont material on amazon for $11, a fraction of the price of the ribbon cables. But again, these are terrible, don’t waste your time.
JST/XH Cables
I do not know if these cables are called JST or XH or JST XH. The main reason I did not use them sooner is because the information I found about them was ambiguous. However, these are the new meta. They are strong, polarized, easier to crimp than dupont, and cheaper than ribbon cables.
They have a male housing which you can solder on to your bus board and modules which is more durable than bare header pins.
A majority of JST XH cables come premade. Usually the wire is crappy on the premades. It makes more sense to make your own.
Also, it seems in most cases that one end of the wires are soldered directly to the board, with a singular female header on the other end. We are not doing that here, you want female headers on both ends of the cable. So if you buy a kit like this, which claims to have 50 sets, just know it really only has 25 sets. so you can make 25 cables for $8. which is less than half the price of the ribbon cable. they also take up a lot less space on your circuit board because it is 4 pins instead of 2x5.
They also take up less space in the case, as they are just 4 wires braided together.
NOTE: The pin connectors (the things you crimp onto the wire) are smaller than dupont pins, so they are not interchangeable.
On Crimpers
I have seen a lot of talk about JST XH requiring expensive crimpers. this is not true, I use this $10 crimper and it works fine.
On Wire
You want to use decent wire for this. The stranded wire that comes in a box with 5 colors and like 30ft for each color that you find on amazon is not good enough. the shielding on the wire is too flimsy. The wire sold at tayda is good. The plastic is more durable allowing for a more solid bite when you crimp.
On Braiding and Configuration
I braid three strands of wire and then wrap the fourth strand of wire around the braided wire.
I use 4 wires because I pass +12v GND +5v -12v from my power supply to every module. You can omit the +5v if you do not need it, but I think continuing to use 4 pins is good practice because you may want to add +5v later and you will already be set up with that standard.
On Time Consumption
It takes me like an hour to make 8-10 JST XH cables. While that sounds like a long time, if you are DIYing every module, it is going to take you months to make 10 modules and you will probably only have to make 10 cables twice a year MAX.
Future
The module I am currently building is the Erica Synths EDU HiHat synth. Which suffers from the same problem of needing switched jacks. My breadboard version of it works except for the Decay potentiometer, which only works when a mono cable is plugged in to the Decay CV jack because I am not using switched jacks. To be honest, the edu line has just given me a bunch of issues and I am probably not going to be making any more of them. I am sure it is user error, and if I just bought the PCBs instead of stripboarding them they would work. But using switched jacks… come on. They are also not that abundant or easy to find.
The immediate goal is to make a full drum synth. Kick, Snare, Hihat, Toms, and some extra sounds thrown in via Hagiwo’s sample drums. I am almost done with this, I just need to finish the Hihat module and a snare module. After that I am going to look into utilities for the drums, like a filter, another delay, and a performance mixer. The mixer will have 8 channels, a send and return, and mute switches.
