Colourblindness and gear

Wondering if there are others out there who are colourblind and have troubles with certain hardware/software. I’d love to know your experiences with certain gear and maybe workarounds? Also I hope to spread a bit awareness among product designers to not just rely on colours; 1/10 men is red/green colourblind.

Mode indication though coloured leds is by far the biggest problem for me. For example: I had to sell the Octatrack because I couldn’t see the difference in leds between a muted, selected or inactive track, leading to big troubles in a live situation. The Antimatter Brainseed module also does mode indication with colour, but only has three max modes and always starts in mode 1 with the leds being off, which luckily makes it countable. Oh and I’m staying far away from Bastl modules with their over use of rgb leds.


This has certainly come up at times in the past – I remember a discussion where we were discussing the aleph’s white (level) then red (clip) meter indication, to which a number of people commented they were never able to see the colour change.

Of course one of the hardest things about this kind of perceptive difference is, as an outsider, it’s difficult to imagine / intuit what will cause problems. Perhaps this would be a good time to link to any references about colourblindness-aware design that anybody has found helpful? I assume there must be a lot of research around as it’s so common. Are there visual filters (phone apps?) that simulate the difference?

As an aside, I’ve been working on a document outlining my design & mfg process, one element of which is a discussion of ‘accessible design’. I’m absolutely no expert, mostly wanting to make people aware of the concept, but I wanted to at least reference colourblindness & handedness as important considerations in a hardware design. Maybe it’s too far off topic, but perhaps there’s other accessibility oriented design guides / techniques / methods that we should be aware of.


I remember seeing more in Apple’s Human Interface Guidelines, but when I look now, it seems there’s only one very general point about color-blindness:

Although color can greatly enhance a user interface, make sure it is not the only source of information. A color blind user may not be able to distinguish between two objects that differ only in color.

This is easier to do in software than hardware I think, but it would seem that one hypothetical UI answer might be “use a row of 3 lights with printed labels instead of one light that switches between 3 colors”.

A difficult task while maintaining a minimal aesthetic, for sure

Not just aesthetically but also cost / space wise in some cases. However I generally like to avoid using color as a primary indicator of anything and only as additional information.

Yeah, definitely that too. More parts, more board space, more HPs…

I always liked Modcan’s method for indicating states on some of their quad digital envelope and lfo modules.

They use led blinking rather than colour. Unlit, solid, slow blink and fast blink. It works well and you can quickly ascertain what the module is doing using a single led colour.

This is an excellent chrome extension for simulating all sorts of vision problems. Unfortunately it requires that whatever you’re testing be viewable in a browser, but you can always take a screenshot of something and drop that into Chrome.

Here’s another tool, limited to color blindness simulation, that runs at an OS level, so you can filter your entire screen.

I really appreciate Microsoft’s recent emphasis on “inclusive design”. Inclusive design goes beyond accessibility to acknowledge that each and overy one of us is differently abled in one way or another. There’s a downloadable PDF manual for inclusive design at this site:

I’m always eager to discuss accessibility/inclusive design issues. It’s something I’ve gotten up on a soapbox about many times over the years.


If there is a deuteranopia setting on said ‘anything’, I have to flip it on or be in for a hard time

That’s a cool idea. Doable with digital pretty easily. Probably a bit harder with pure analog modules.

Good for you. It’s something I think has been an afterthought at best for too long. I work with adults with developmental disabilities so it’s something I encounter and is on my mind quite often.

Yes, my coding knowledge extends as far as MaxMSP but I can see in my head how to do it for that. Pure analogue on the other hand - how would it work? Would you have to add a little bit of digital into the analogue circuit to read it and output the led appropriately or would it be doable in a purely analogue way?

1 Like

So glad to see this thread! Yeah, I am red-green-colorblind.

I’ve written to Elektron several times about this (and yes, I even used the argument that their current strategy reduces their potential customer base by 10 percent), but alas, no change. I use their instruments a lot, mostly A4 and OT, and they require a lot more attention to grasp their track states. But ultimately, at least for me, the benefits of these instruments still outweigh the additional effort to track their tracks’s states, as there are still other ways to find out what is going on.

About 10 years ago I was contemplating purchasing a Genoqs Octopus hardware sequencer, contacted the manufacturer in Germany and finally did some tests with alternative colored LEDs. I found out that red/blue LEDs do work for me. Genoqs would have been willing to do an Octopus with red/blue LEDs, but went belly up before the project went further.

I would love to use The Harvestman Hertz Donut MkII, but I failed to decipher its states when using a friend’s system. So I wrote to Scott Jaeger, who was kind enough to not only answer, but research for alternate parts. The LEDs are integrated into the button assemblies of the Hertz Donut, and unfortunately he can’t find red/blue LED button assemblies at his suppliers.

So I’ve been visiting the Enchroma glasses website quite often for over a year: They claim to have developed multiple notch color filters which attenuate certain colors, so that the colors which humans with colorblindness have difficulties differentiating stand out more. That was a complicated sentence for a non-native speaker.

Being based in Europe, I have not yet found the guts to order on of their glasses. At the same time I ordered & imported quite some Monome modules, so you see where my priorities are.

Might this be difficult for humans with epilepsy? Just guessing from the video game warnings.


My knowledge of epilepsy is reasonably limited. My gut reaction is that it probably wouldn’t be an issue - a strobing 50 inch TV screen and a blinking led are quite different things though in terms of how I could see them effecting people. But, epilepsy is so individual that you could ever say that with 100% certainty.

I had a quick look here:

and for me the most pertinent piece is:
The frequency or speed of flashing light that is most likely to cause seizures varies from person to person. Generally, flashing lights most likely to trigger seizures are between the frequency of 5 to 30 flashes per second (Hertz).

The Modcan modules I have that use this method might hit 5hz frequency or a little faster on the fast blink. But, I’m not sure - I’d have to try to measure it to see.

1 Like

I’m not terribly familiar with the details of epilepsy symptoms, but I image any modular system is probably not going to be a good fit for someone with that condition. There’s blinking lights everywhere, and especially for things like LFOs they’d be right in that range.

1 Like

Just wanting to chime in as another red/green-type color-blind fellow.

The Elektron gear can be difficult to decipher, what with amber/green/red/yellow LED color choices.

Thanks for this thread.


I have worked with a lot of people who have epilepsy but I am not a clinician so my experience is more around supporting people to deal with the effect it can have on their lives.

I looked up some figures.

Approximately 1% of the general population have epilepsy. Of those around 3% have some form of photosensitive epilepsy. But, not all people with photosensitive epilepsy will have a seizure triggered to led flashes. It’s very individual what triggers any type of seizure in a person. Take this small subset of the population of people who have photosensitive epilepsy and find the number who are also modular synth nerds. Then we’re talking even smaller numbers, even with the eurorack explosion of the last few years!

So, while I think it is great that we are considering how something like a module interface could affect an individual with epilepsy the likelihood of it actually happening is very, very low. It’s not like modules are selling in the tens of millions like a Playstation 4 for example. There, while the likelihood is still a very small fraction of a percent of the purchasing population, it is probably big enough to warrant putting a warning on the startup screen and in game literature.

I think a simple warning regarding photosensitive epilepsy with any module utilising rapidly blinking leds would suffice.

Wow, I’m a bit positively overwhelmed by all the responses! I was afraid putting the topic up, knowing that if I would post this on the-forum-which-shall-not-be-named I would be made fun of. Thanks for being such an inclusive community!

As a alternative to blinking leds I like what happens on the Mutable Instruments Peaks and ES Disting for example; patterns made with a couple of monochrome leds. Footprint is marginally less more than a rgb led especially if you’re using smd parts. Prob easier to code than blinking as well for analog circuits. And I think its more aesthetically appealing than a rgb led (but hey I’m colourblind).

Another example of accessibility I want to give is the Teenage Engineering OP-1. Although it relies heavily on its display, it tries to be more accessible with braille (but just on the back).

I went to the museum of the blind in Berlin once and had a tour by a blind person, which ended with him showing how he interacts with the computer and iPhone. (The iPhone has some really nifty accessibility features next its screen reader.) The whole museum was a really valuable lesson in designing for different senses.

I’ve been drooling over those as well. But the risk of them not working with no easy return + customs (costs+bureaucracy) has put me off. Guess I’ll have to wait till they ever appear in-store in Europe.

Adding on: doesn’t help to have problems with red and green leds.

Indeed. I did a little colour-blindness research years ago and the OT would come up a few times as a very problematic device to work with.


Interesting, I remember bringing red/orange/yellow/green LEDs up as an issue when I still was at Ableton and they released the APC40 and I was like “wait, what, I cannot follow with that colour scheme” in a presentation. I cannot really tell the “active” slot on the octatrack via the led but of course I see it on the display. My sequencing needs are not superdeep, so that was kind of OK.

I was shocked the day I realized that one of the best visual designers I’ve ever worked with (he had done icon design for well known Apple apps) was colorblind. When I asked him about it, he explained various tricks he uses to cope but also admitted it was a serious challenge at times. Needless to say, he was very supportive of accessible design!