Brendan Power & Alternative Harmonicas Forum

Hi everyone! First time posting on this forum.

I was wondering if anyone knew about what vertical-slot chromatic harmonics were out there. (Or really any chromatic that is draw over blow and blow over draw). I was looking to work on my own custom valveless chromatic with this format.

I know there is the JDR Trochilus and the Hohner Koch, but one has a really strange comb shape and the other appear to not be made anymore (?). Also, they both only have 10 holes.

Also, a bit unrelated, check out this parametric model for a vertical slot comb I made in FreeCAD!

Welcome to the Forum, Justin!

The vertical slot chromatic concept is a very old idea, dating back to the 19th century. Here's a patent drawing from 1899: In the mid 20th century the design was used by a couple of lesser-known manufacturers for chromatic harmonicas. Here are a couple of photos: The inventor/designer Finn Magnus used it in a highly innovative chromatic harmonica with plastic reeds. Here's his patent drawing: Hohner experimented with it in the 1920s, but never released a commercial model.

I've also made quite a few home prototypes using the vertical slot comb/slider design for various design ideas.

So as you can see, the Trochilus is nothing new! But its success is certainly bringing back attention to this excellent slim comb configuration for chromatic harmonicas.

One problem you may not have considered: where do you get the reedplates to fit your 12-hole vertical slot comb design? It requires reeds with even spacing. Currently most commercial 12-hole reedplates have the blow/draw reeds clustered in pairs (not ideal, because the internal valves will hit the comb dividers). The Easttop Forerunner has 12 hole reedplates with evenly spaced reeds... but they are not great quality (quite airy), the reed directions are not optimal, and the tuning is not configured for the vertical slot comb design - so lots of retuning would be involved.

Thanks for the response Brendan, it was very informative. I didn't know that vertical slot chromatic had such a history.

So it sounds like there are no harmonicas being produced right now (other than the Trochilus) that use a vertical slot design or could be easily converted to one...

I mean I could always alter my comb design to accommodate the irregular reed spacing of most chromatics however there is also the issue of the blow and draw reed being situated above one another instead of alternating. It sounds like if I wanted to continue with this project, I'd have to reach out to someone like Seydel for custom order chromatic reedplates with my note layout. (unless you can think of another option.)

Edit: It looks like JDR Quartz Chromatic might be a good candidate.

It is worth noting that at SPAH JDR announced they will be releasing a 12 hole trochilus. But I don't know when.