How do you map the triggering of sample slices to a range of voltages?

What’s the best way to map a particular note(voltage) or range of notes to a sample slice? Say I want to lay out a drum kit, with C1 being the kick, D1 the snare, E1-A1 the low tom, etc. I would like to be able to use one gate and cv in to trigger any of those, based on the voltage. I understand that if it’s one audio channel, you can only play one sound at a time. How does the mapping work in the ER-301? Do you need a custom unit, or is this something that you can set when you map a gate to a trigger in a sample player?

Similarly, if I wanted to use a second voltage to select from a number of sample slices, for example key velocity to cv to play a harder hit snare as velocity increases - can you do that?

I was looking at the piano16.lua file for clues, but I think I’m asking for a way to be more explicit about mapping notes (voltage) to sample slices.

Apologies if this has been already covered (or if it’s obvious and I’m just missing it) - just please point me to the video or post.


I think this feature is still on the to-do list (mapping slice selection to notes). There have been some pretty successful tries at mapping slices to different notes, but it is not perfect so far – did you try searching?

I did search, the closest thing I could find was the thread where they mapped a range of voltages to a range of sample slices, leading to the piano unit. But (as far as I can tell) that was done in a custom unit, correct me if I’m wrong. I’ve been watching Neil’s videos, scouring the forum here and the old Google group, but I couldn’t tell if this was something that just didn’t exist yet, or if it was simple and I just didn’t see it, or what. I’ll write a lua script if that gets me where I’m going, once I figure out how.

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You don’t need a custom unit - although these can be very useful! You don’t need to write any Lua either - that should never be necessary :sweat:

All you need is a sample player, slice your sample. These slices are distributed over the incoming voltage range.

Place a slowish sine oscillator on your trigger input to keep it triggering and send the sample player your range of voltages. It should become clear which voltage triggers which sample. Adjust the gain on the slice parameter to adjust your incoming voltage range to match the range of the sample slices.

If you want multiple sounds on one channel, or a stereo pair of channels, add a mixer and place your units for sound one inside the mixer, then return to the top level and repeat with another mixer for your second sound, etc…

Velocity is not implemented, but you could achieve something similar with by sending your velocity information to a VCA or the sustain level on an ADSR unit perhaps.

Have fun :slight_smile:


12ET slice addressing mode has been implemented in the Sample Player. :smile_cat:

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Ahh, my bad! :slight_smile:

Ok, I’ll bite… what is 12ET slice addressing mode? I’ll admit, I actually had to Google 12ET, that’s your typical 12 tone classical tuning, I get that now. How does it work? I’ll gladly read up if there’s something already written, I just haven’t had luck finding anything.

Related, what if you have a bunch of individual files that you want to assign to different notes? I have samples that are each a single drum or other percussive hit. Do I have to first combine them into one file such that I can then slice it?

Sorry so many questions, I’m going to just fool around with my ER-301 and see what I can figure out based on the responses so far.

it’s typical 1 volt per octave pitch tracking in eurorack land… so you can reliably trigger different slices based on standard tuning from a CV keyboard, sequencer with a quantizer or similar.

A good example of how this is practical:

All right, I finally got a chance to come back to this. Thanks for the responses! I’d read the piano16 thread before, as well as the one discussing voltages, but I was having trouble applying that to my basic example. I think I have it sorted out now. I made a single wav file with 19 different drum sounds, loaded that into a sample player, and sliced it appropriately. I didn’t have to add extra slices to mark end points, because I didn’t leave any extraneous space. I assigned G1 as a trigger, and added a 5ms delay to allow the slice voltage to register before the trigger fired. I assigned A1 as the voltage input to the slice select on the sample player. So here’s the main thing I had to figure out - I adjusted the gain until I got a good range per sound - 2.50 gave me ~3 notes on the keyboard per sample slice, which seemed to work. I realize now that I can use that gain adjustment to control the slice distribution across the keyboard (rand of voltages) .

I’m not sure I understand this yet:

What does that do? Does it allow you to control the respective volume of the various slices? Or are these now 2 sample players? Can I then trigger 2 sounds simultaneously (currently I can only fire one at a time, so if I want e.g. a kick and a hit at once I need to load the chain on 2 different audio channels)?

You got it :slight_smile:

It’s probably worth reading this discussion

Yep - you can have two or more completely separate mixer channels on the main ER-301 channel, the sample player inside mixer channel two can have it’s own sample, input trigger etc…

Repeat and build a full drum kit…

I always switch to the admin panel and set channels 1 and 2 on the ER-301 to be a stereo pair and then put the kick on channel three. Channels 1 and 2 give you pan so you can space your kit out nicely with all the mixer channels and channel three gives you a centre kick. It works really well :slight_smile:

Did you go into the Sample Player’s menu and set the Slice mode to “12ET” ??

No. The 12ET slice addressing mode was mentioned, but I didn’t realize it was a setting, or where you had to configure that.

find it ok?

It’s in the menu of a sample player, right-most option.

Oh yes, I figured it out as soon as you mentioned it. I just didn’t know to look for it before that, thanks! :slight_smile:

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Sorry, meant to follow up with the results once I sorted it out. I used the 12ET Sample Player slice mode. I had to remember to reduce the gain from the previously mentioned 2.50 to 1. After that, everything worked beautifully - each key on my keyboard triggered the slices of my sample in order.

Thanks again!