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Sampled Chord Bank

Hello everyone. I’m thinking of creating a sort of chord bank sampling my Peak. What would be the best approach?
I thought I could record 3 inversions of each chord in 3 different octaves and create a bank for Ionian and Aeolian repeated for each note to be then selected with a cv, but that would be extremely time consuming. Is there another way?

Sounds doable, ive done something similar. I think you’ll have a hard time generating something you can use in any future composition, but it works well for some confined application, like the track you’re working on now :smirk:

Selecting the right slice with cv is obviously easier if your “selection device” is flexible, I’ve done this from voltage memory and teletype.

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It would be a sequencer to select the exact slice.
My intent is to have a general purpose bank, with multiple scales in it to be reissuable.
Questions are: do I record every chord o I pitch shift? (Something like plus-minus 3 degree in the scale for each major and minor)
Should I go for single cycle?

When I’ve done this i didn’t transpose on the 301, but i guess it depends on your raw material.last time i did this was with acoustic piano…

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Single cycle won’t work well for most chords. If you pick the lowest note’s period as your single cycle, the other tones will sound hard synced since they will reset in the middle of their cycles (unless using even-multiple chords like octaves and fifths).

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Yeah that was my concern.
I think I’ll sample an octave range with all the minor scale chords and the major ones, with inversions. Full sounding to be subracted in the system.

Something like (r as root position, 1 and 2 inversions):
Cr C1 C2 … BdimR Bdim1 Bdim2

CminR Cmin1 Cmin2 … BR B1 B2

Two separate presets, so I which one I need and selection is more precise.

Does it make sense? Cause that’d be just C

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I’ve thought about doing this too. Also not sure if I want full blast chords with completely open envelopes and filter so I have more flexibility in rack to shape, or make the chords “beautiful” and standalone - like samples I can just trigger as opposed to chord oscillator style. Maybe something in between - sweep the filter or PW and use the shift parameter to get different timbres from the same chord slice - maybe even change waveforms or have several slices dedicated to same chord flavor.

As Neil suggested, the switch with bump scanner method works to select between 2 units, so that I can send a cv to toggle between minor or major container and then v/oct would tune the chord. @Joe would it be possible, dunno how, to set it up so that if receiving c f g it toggles the major container and with d e a the minor one? Of course, this for major scale, needing a different configuration for minor

You’d need something to serve as a lookup table for which notes go with major and minor. A voltage bank unit from Accents might work as long as you’re dealing with an 8 note scale and only need to cover 1 octave. Otherwise you’d probably have to custom create a wave file for the Sample Scanner unit.

Oh that sounds cool. I get the first part but I’m missing the principle of the wav file thing

The Sample Scanner can be like a highly customizable version of the bump scanner. You could use it to generate high/low values for specific input values/voltages that will control VCAs. But it needs a wave file to use as the map. For a 7 note scale, say C major (Cmaj Dmin Emin Fmaj Gmaj Amin Bmin rather than diminished for simplicity’s sake) the wave would look like a pulse wave

HI - LO - LO - HI - HI - LO - LO

Where HI = major, LO = minor. Send the output to a VCA that selects the sampler with the major chords. Invert and offset the output so low is back at 0, and send it to a VCA controlling the other sample player that handles the minor chords so neither is playing at the same time. For selection you could either put the VCA after the samplers to essentially mute them. Or you could put them after the gate signal going into the sample players’ triggers so that only the correct one gets triggered.

The wave file can be any length, it would just need to be evenly spaced. E.g. like if each HI/LO pulse is 0.5 sec, the total length of the WAV file would be 3.5 sec to handle 7 notes. You could probably record a gate sequencer output into the 301 to create it.

Hopefully all that make sense. It would probably be easier visually. I can’t remember if I did any videos using the sample scanner like this.


Beautiful, I’m reading this multiple times before bothering again. Thanks Joe

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If you have questions feel free to ask, I’ll help if I can.

So if your goal here is to level up your 301 wizardry, I’d highly recommend trying to get this project to work this way. In the custom and middle layer units I’ve made, I’d say 90% of the time is spent figuring out the right signal routing and signal conditioning to make whatever magic trick happen. Only about 10% of it is spent actually implementing it in code or the UI. If you figure this out, you’ll learn a ton about selection, signal conditioning, and signal routing in the 301.

That said, if your goal is to create something that takes a single gate/cv pair input and spits out traids in the correct key, and is easy to build and flexible to reconfigure, I might go a different route.

I think I’d try sampling individual notes. Slice them up and load that sample into 3 sample players in 12TET. Mix their outputs. Then mult (internally) the gate and CV signal coming off your sequencer. Send the gates to all 3. With the CV signals, offset one by a 3rd and one by a 5th, and run each through a Scale Quantizer unit.

I think (?) that would be a lot simpler and would have the advantage of being able to control the level of each note individually. And if you want to change scales or key you just go adjust 3 quantizer units. If you decide you want suspended 4ths instead of traids you just go adjust one Offset unit.


I already tried in the past the quantizer way, but I remember that setting up the cv to “fall” into the right segment of the wheel might be too much or not enought for the next chord, ending up with sus (that’s due to minor and major 3rds, same for 7th). The goal is having something like a Harmonaig, both with internal osc and samples (separate notes or entire chords)

Did you check out sam barkers website? He did something similar for polys and his octatrack
maybe the midi files could be of help
his site is here: https://www.voltek-labs.net/octatrack

I don’t think midi is an option here