Meta Morph for Eigenharps

for last few weeks Ive been working on adding native support for Eigenharp’s to vcvrack.

It’s going to be a niche plugin suite (given number of Eigenharps in existence), but I thought it might be interesting to those here to see some direct hardware support in VCV.

from my initial testing, I have to say its a match made in heaven…

VCV Rack brings the flexibility and the vast eco-system (of modules), and being able to write native modules for vcv means I can expose the Eigenharp’s high resolution (10bit) , and low latency (2kHZ sampling), that is just not possible via midi , or even osc.

anyway, hope this shows something a bit different :slight_smile:

btw: are there any modules capable of MPE Output ?

(if not, I may need to create one… no big issue… but don’t want to reinvent the wheel)


Amazing. I think this kind of custom handling for specific hardware has some amazing opportunities. I’m kicking around something similar for Osmose (and I don’t think I’m the only one…)

Eager to see where this goes!

FWIW I haven’t seen any MPE output modules but it’s possible that I’ve missed something.

EDIT: This is over i2c, right?

yeah, I agree…

an interesting historical tidbit,

Eigenharp were released with software called EigenD. EigenD was a (custom) virtual modular systems. (racks n’ wires, about 15 years ago!), even supporting polyphonic wires, vst hosting, and its own oscillators/sound modules.

the reasoning behind this was the founder of Eigen Labs (John Lambert) did not want to restrict the Eigenharp to the limits of midi. he wanted the Eigenharp response couple at audio rate to the sound engine… not going thru a (OS) serial pipe.

so in many ways, I see VCV rack as very much in the spirit/dna of the eigenharps.

no, it uses a proprietary isochronous usb protocol, similar to a usb audio interface… it does this so it can be low latency, have high bandwidth and be guaranteed timing.

these two things, combined to what make the eigenharp special…it has remarkable end to end latency, and high resolution - many have remarked how you feel ‘connected’ to the sound.

and thats made possible by combining this low latency usb, and hitting the sound engine directly.

bring in VCV , and we now have a format that users are familiar with, and has a huge variety of sound sources… its a heady time…

btw: the reason Im asking about MPE Output is: one of the design goal behind meta morph is to allow the full control of a performance from the Eigenharp…

so whilst I’ll primarily use VCV sound engines, some still like to use external synths (software / hardware) in combination - so I want to enable this.

for the same reason, I may need to consider implementing an MPE enabled VST host , as I believe the VCV one is not capable of MPE at present?!

(again, Im really trying to reach some sort of feature parity with EigenD!)

Do you mean ‘sending MPE out of VCV Rack’?

MPE is not much more than multichannel MIDI, but most Rack MIDI output modules force you to select a single channel. Some Entrian sequencers do let you select the channel for notes sent, but may not be as dynamic as what you’re looking for.

Browsing what modules I currently have, the focus appears to have been on midi input, where there a few that handle MPE input (e.g. Ahornberg and MoDLLz). There could very well be modules that do emit MPE, but it’s buried in their menus or docs, and not apparent on the surface.

For Eigenharp->MPE, you’ll likely need to make your own module suited for the dynamics of that instrument.


the issue is… the VCV midi output device is tied to a single channel, so is not suitable.

so yeah, I think, I think I’ll need to write my own MPE output module. no big deal, I’ve written this for other platforms - so its straightforward.

Similarly, VST host looks like its similar … and has no explicit support for MPE. you just have cv/gate, and then automation channels, no way to give it pressure/cc74 (polyphonically attach to channels) (*) again, not a big deal…not quite as simple as midi output, again Ive created vst hosts before, so it’ll be ok…

though I will be careful it does not appear to undermine VCV Host, as I do believe users should be buying vcv modules and pro, to help support its development !

good news is an mpe output and host would be usable for other devices too, so not tied to the eigenharp at all.

(*) this is the bit I need to check, from the quick look I had, it seem to put things on one channel… but I do need to double check this. its possible ,it could look of the MPE property on the VST, and then ‘switch modes’ automatically… but I suspect thats wishful thinking :slight_smile:

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Don’t know about the VST hosting, but the x-platform Rack MIDI API works fine for direct multichannel MIDI output, so there’s no need to build something special for that layer. I’m using it in my plugin for EaganMatrix devices. An MPE output module would be a natural fit as part of my plugin, and planned to do it eventually.