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I2C setup with 16n Faderbank

Alright, so I have modded my Er-301 following the instructions and plugged in everything. When I move a fader I do see some sort of signal on my ER-301 but I am not positive that is what I want, i hear some audio as well… here is a pic.

I guess that is an audio signal? The port does not move. The rightmost unit does and I hear a faint sound on my headphones.

Have you read this to understand how those units work?


Yes, I briefly looked it over. I don’t seems to be getting any signal from my Faderbank. I did just upgrade the OS to the Latest version and was able to set it as Leader in the new Web Editor in version 2.01 … Hmm I will keep troubleshooting. The CV outs do work as expected on the Faderbank. It’s probably my cable. I ended up doing this

since I was not able to find a male to male 1/8" TRS cable in my house and the guy who sold me the Faderbank told me that’s how he was using it.

You just said you were getting a signal in your previous post though? From your description it looks like its working to me. :thinking:

Not positive about the signal. Going to bed, I will check again tomorrow. I am recording the whole process and will make a video once I am done in order to ease the process for other in the future. Thanks for the help so far. I am also super new to the ER-301, only had it for about 3 weeks.

Your pic shows an output channel where you have inserted an sc.cv unit. This won’t do much…

  • clearly you getting a signal in from the 16n, which is good!
  • the port fader won’t move with fader movement.
  • you’d set the port fader manually to the desired fader you intend To give a certain function
  • the sc.cv units output cv signals which are static until you move the fader
  • take an audible osc for the output chain, and add the sc.cv unit to a sub chain, e.g. frequency control or volume.
  • don’t forget to increase the gain setting of the subchain where you inserted the sc.cv unit in! Otherwise the fader won’t affect the sub chain

The faint sound you head was just a high pass filtered version of your SC.CV output because the ER-301 does not output CV. The bar graph signal indicators are will react briefly to changing CV since they are also HP filtered. The scope view in the second screen will display DC signals though!

Try this patch:

Sine oscillator unit > Unipolar VCA unit > Output 1
                              ^(Gain x 1, bias 0)
                         SC.CV (port 1)

Now you should be able to control the output level of your sine oscillator with fader 1 on the faderbank.

After you verify that this works, I would recommend that you disconnect the faderbank for now and practice making a simple subtractive synth patch controlled by the CV inputs. You are just beginning your ER-301 journey and the faderbank will be a useful tool once you understand the signal chain!


I am pleased to report, SUCCESS! I had a couple issues, one of them being not knowing how to use the SC.CV unit, another one was related to the cables, but now everything is working. I will make a little video out of this hopefully this weekend.

Thanks a lot to those who helped out! @odevices @mopoco and @desolationjones ! I for sure have a lot to learn but hopefully the Faderbank will improve that process a bit.

Also, if anyone else needs Dupont cables to build your own cable, let me know I have a ton left over I can send to you for the cost of shipping which is probably just the price of a stamp. Cheers!


Thank you so much for this! Works perfect for me - you saved me from lots of despair and frustration.


my 301 also doesnt want to react on the faderbank via i2c. i have a rev 10 so no need for moding the 301. I’ve built my fader bank on my own and everything works fine when it is connected to chrome. also the cv outs all do work fine and are giving me smooth 5v. i followed all the connection instructions. but using a 6,3mm female jack (wich will be later on one side of my case and connected internaly). i do have continuity to all the connections of the 301. tip is sda, ring is scl, sleve is gnd. I had to solder cable from 6,3 to 3,5mm stereo jack. my guess now is that the solder connections of the cable are not the super best ones i ever did but i do not have a short and for audio this would be definetly a go, the cable is 40cm long. could it be that the cable is my problem ? does the cable have to be a sheelded one ? btw i changed all the ports on the faderbak to cc1-cc16 and midi channel is 1.any help is appreciated

did you make sure to add the pull up resistors to the 16n board?

Di you follow very carefully these steps?

yes I did.

@koku I didn’t as these are for the sweet sixteen mk2. im using the classic 16n faderbank. do these also count for the normal faderbank ? I guess I will have to rework my cable. did anyone ever use a 6,3mm jack for i2c communication ?

Can’t see why the size of jacks and plugs would matter…
As for the compilation part of the firmware, please try
The firmware I posted before. It’s working for traditional 16n faderbanks and this way we can rule out that the problem lies with the firmware part.
But let us also know about your process how you’re actually assigning The i2c units inside the er301.

  • turn on i2c in global settings
  • insert sc cv unit E.g. in a Vca or osc Pitch
  • assign port 1
  • One level up: set its gain From 0 to 1 and see whether the modulated unit reacts to fader movement
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thx. @mopoco i did install your fimware, on chrome all is good all the faders are recognised and working,flipped mode is quite useful and handy i think. i did assign the cv unit to a level fader gain on 1 sadly i do not have any reaction. i guess i have to rework the cable. the connections are tip is sda, ring is scl and gnd is sleeve.

I received my 16n from local engineer and i2c cable (3.5mm -3pin). Yesterday I spent some time on preparing (config Er301(rev10), FW on 16n) but still no results.

After it I look at this thread and found that R17 and R18 should be soldered. Is it must have (I see that both resistor need to be soldered)?

In case you want to connect the 16n directly to the er301 those resistors are obligatory
As well as the master/leader version of the firmware… The er301 being slave/follower.

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I set the master on 16n, just need to find the engineer who can iron smd components:) they are so tiny

due to the lack of smd resistors i put simple through hole ones on there…