Page 1 of 1

TWIN-CHROMATIC

Posted: Sat Dec 23, 2017 4:15 pm
by Slava
Hi! Brendans twin-chromatics is a great thing! but it seems to me that they are not very popular for some reason...maybe its price...
so i have a question about them, are they airtight as usual chromatic? and airtight enough for half-valving? and could it be half-valved and bend?

Re: TWIN-CHROMATIC

Posted: Sat Dec 23, 2017 4:28 pm
by Brendan
They are selling pretty well thanks Slava :-) And yes, they are perfect for blues style bending with half-valving, as you can see in this video by Boris Plotnikov:

https://www.youtube.com/watch?v=A36Q1_DoRig&t=26s

Re: TWIN-CHROMATIC

Posted: Sat Dec 23, 2017 8:27 pm
by Slava
No, Brendan , Im talking about twin-Chromatic, not twin-Diatonic ;) :D

Re: TWIN-CHROMATIC

Posted: Sun Dec 24, 2017 8:28 am
by Slava
Its called the Double-Chrom on your web-site, it is 2 cx-12s

Re: TWIN-CHROMATIC

Posted: Sun Dec 24, 2017 3:16 pm
by Brendan
Ah, the DoubleChrom - sorry! You're right, there are not a lot about. They're expensive and perhaps add more note options than most people want. Roni Eytan uses his Quartertone version quite a bit in groups with Middle Eastern musicians, and has developed a good method of controlling the sliders. Here is a track:

https://www.youtube.com/watch?v=PANGhLYMZ5E

I have made one half-valved version of the DoubleChrom in PowerChromatic tuning for a guy in Taiwan. It bends the notes, but only worked decently after I embossed the slots. With the increased distance to the reeds and the addition of extra sliders, these instruments push the boundaries as it is with regards to Helmholtz issues and airtightness. Removing valves adds another level of difficulty with making them play well, so I don't advise it.

Re: TWIN-CHROMATIC

Posted: Sun Dec 24, 2017 9:06 pm
by triona
This one is really great:

https://www.youtube.com/watch?v=dMnqCs1S9qc

The very specific features together with the - necessarily - high price might be some reason, why there are not so many outside. But for an idea like this quartertone harmonica it is necessary or at least very useful to use an advanced technology like this, so that the high price might be secondary. It might not work as good as this otherwise. But the request might be quite limited.


A question about your new Compact CX-12 Double-Chromatic as seen here:
https://www.youtube.com/watch?time_cont ... ooqEjKKBUg

Did you cut the original housings (shells / covers ? - I dont know the correct word) of the two CX-12's and weld or glue the parts together, or did you print a new unit?


dear greetings
triona

Re: TWIN-CHROMATIC

Posted: Mon Dec 25, 2017 5:07 am
by Slava
Ok Brendan, I see, thanks for the answer.. I hope some day you will find how to overcome Helmholtz's resonance..
And this guy is playing and sounding great!

Re: TWIN-CHROMATIC

Posted: Mon Dec 25, 2017 11:36 am
by Brendan
Thanks for the comments, Slava and Triona.

Triona: The CX-12 version of the DoubleChrom has been superseded. I have moved to a new design that uses a single rear slider I make on my laser-cutter. It is easier to make overall and uses the double-screw attachment system of my TwinDiatonics for easy disassembly.

You can see photos of the first prototype, which Roni Eytan is testing for me. He plays it in this video:

https://www.youtube.com/watch?v=hWlSEReYoIA

Since this video Roni visited me and we did more optimisation in my workshop (embossing, making sliders move more smoothly etc). This is the current version, but not the final one! I'm now working on an alternative smaller type, which I hope to be able to announce in January. It will reduce the distance from mouth to reeds, so should help with the Helmholtz issue.

Re: TWIN-CHROMATIC

Posted: Mon Dec 25, 2017 1:06 pm
by triona
Ok. 2 sliders seem to be better than 3 indeed. Not only from the production as well as from the Helmholtz issues, but at least certainly from the handling when playing. Usually the less complicated does better in the practice.

But I can not imagine how this construction with the screws and the large washers would work with the design of the CX-12. (See my question above.) Does that mean, that the CX-12 is no base for the Twin Chromatic to you any more?

Why do I insist so much on the CX-12?

It is the easy change of complete "sound-Units" (= comb + 2 reedplates readily mounted) through the "back" of the housing by unclamping the spring after the "one-touch" removal of the slider. (I guess on your Twin device this is as easy to do as on the original slider of the CX-12.)

For a "big investition" like the Twin Chrom technology, it would be not bad, if there were this possibility for a quick and easy change of whole "sound-units". In my eyes it would enlarge the possibilities of the instrument substantially - talking about the availability of possible different tunings or reedplate combinations.

Are the surfaces of the combs of the Suzukis facing the slide unit specially milled (sanded, lapped ...) or are they like serial production? In the case of the CX-12, there would be definitely no necessity of processing the serial units before using them in the Twin device, as long as the double slider is sliding on the surface of the combs like in the original construction. At least as long as the leakproofness of Hohner's original is considered to be sufficient. Or am I in error with this concerning the design of the double slider (the secondary directly in front of each comb) of your latest Twin device?


I hope it was understandable, what I am aiming on.


And a further minor question:
Which material are your sliders made of?
Is it a synthetic material?


dear greetings
triona

Re: TWIN-CHROMATIC

Posted: Mon Dec 25, 2017 8:41 pm
by Brendan
Hi Triona, you make a good point about the easy modularity of the CX-12 version of the DoubleChrom: swapping in new comb units is very easy and quick. However the rest of it was very difficult and slow to make accurately. The new design has fairly fast changes of rear units (30 seconds instead of 5 seconds perhaps), but the rest of the positives outweigh losing some seconds.

Anyway, they could be regained with some kind of spring fitting in future - I have some designs for that on trial. Your comments make me more aware of how useful it would be to perfect one, so thanks!

Keeping cost in mind, I have adapted this design for Easttop chromatic harmonicas, which are quite a bit cheaper than Hohner or Suzuki, still very good, and come in a range of keys. DoubleChromp prices will come down for them; announcement in a week or so.

The rear slider is made from acrylic. It is brittle if bent the wrong direction but fine if used in the correct way and handled with care when disassembled.