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Łukasz Martynowicz

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Posts posted by Łukasz Martynowicz

  1. 4 minutes ago, Dashy said:

    Finished the button generation and handrest, the script is set up so you just feed the list of notes and dimensions and stuff to it in a JSON and it builds it! The alignment is a little wonky because I don't have those dimensions available (and the plate the buttons are on is a just a big rectangle because the version of CADQuery I'm stuck with right now doesn't have 2D convex hull working), but nevertheless I'm really glad I printed these out.

     

    With 9mm vertical spacing and 16mm horizontal spacing these button layouts are a bit wide, I think it should be fine but I do want to see if I can make the button field a little more compact before settling on anything. Probably just gonna print out the button field alone for future mockups just to save filament and time, 'cause now I know I'm fine with the size of the box.

     

    Maybe I should design an adjustable mockup jig so you don't have to print out a whole new thing for each layout, just add and remove buttons on the fly... adjustable handrest would be good too... I wonder if anyone besides me would use it.

    Anyway, pictures of my new mockups!

    20220125_144336.thumb.jpg.34ac5348750ee6066809f6e10b9cbf25.jpg

     

    Closer spacing will in turn require smaller buttons, which in turn make the 'tina less comfortable to play and lever routing even harder to solve than it normally is due to less space between button stems. With the above print I already see a huge problem with lever routing, especially LH sharps side. For me, the smallest comfortable buttons are 5mm diameter, with 6mm ones being significantly better, and at 6.5 mm I start to hit adjacent buttons (on the standard 9/16mm spaced array). This translates to a minimum of 6mm distance between buttons, and less than 8mm gain by squeezing your array to the minimum. Put a hand strap on this mockup, and then try to play some tunes with a lot of high sharps and sharp chords in it to see where you can even reach comfortably and then see if this gain is even enough to fit everything within a playable area.

  2. 6 hours ago, resistor said:

    I'm not going to claim to really understand how your "antlers" system works, but I was curious why you're choosing to immobilize the thumb in a downwards-pointing position? It seems like holding the thumb in a bent position like that for an extended period would be painful. Would it be possible to achieve the same effect with the thumb pointed straight, but still in a thimble?

     

    There is a very good reason for this orientation, but first I want to stress one thing - this whole setup is aimed at relaxing the hand as much as possible, so no, there is no pain involved, at all.

     

    The main concept behind this handle design is based on the same principle as rock climbing chock techniques - because of how the thimble, anvil and handlebar parts of this system interact, the thumb is locked in all planes but one (plus the leeway described below) and in all axis of rotation but two. Because of this, the hand is effectively attached to the concertina in a very "glove like" fashion, with all positioning absolute and all lateral thumb movements directly transferring to the bellows movement. You mount/dismount your hand by a move that does not naturally happen when playing but when locked in the hand simply rests, hanging from the thimble in the same position you hook the thumb on e.g. backpack straps when you want to rest your arms, or on a jacket button etc...

     

    For the handle to act as described above, it must be rigid. Any elasticity reduces the absolute nature of finger positioning. Now the main reason why the thumb has to be oriented this way is that in order to reach various areas on the keyboard in finger configurations required by Hayden chord shapes, the thumb must rotate a bit. The thimble is oriented exactly along this axis of rotation. A rigid handle like this, if made with the thumb straight wants to literally break your thumb as you try to reach extremes of the array and even if it didn't you'll loose the hook-and-lock aspect of the handle. During prototyping this I gradually expanded the concept from a simple, english style thumb "strap" (only made from rigid filament) and then iterated it about 20 times to the final shape you see here. There is a short video on the previous page of this thread when I present how the lock aspect of this handle works and how the movement is transferred onto the bellows, and in the final seconds od the video you can see the unlock move.

     

    Now, the common confusion I got about this thumb position is that it is a 90 degree bend. It isn't - it varies between close and far rows fingering and the thimble is not "snug fit" vertically, you can move the distal part of the thumb enough for all movements required. In the "ready" position of the thimble there are two forces acting, one upward acting near the joint and one downward acting at the tip of the nail. Then when playing those forces vary, both in direction and strength, so there is very little fatigue. After a 45 minute session my hand is more relaxed than after playing the same time with a hand strap setup on my CC Elise. This is mostly because my handle design does the gripping for you.

     

     

  3. 10 minutes ago, dabbler said:

    Very nice linkage solution.  I wonder what the lifespan of the Bowden cables is.  I suppose they could be made replaceable if it is an issue.  I'm also impressed with the finish on the handles.  Is that stained wood-fill PLA?

    -George

     

    Those are PTFE, which from I can gather has an unlimited shelf life. With this curvature I suppose there won't be any serious wear on those. But if any part of the link breaks, it is simply push fit into the board with a little notch cut on the button side so it does not slide back in. To completely replace the whole assembly you just need an exacto knife and a piece of tube for the Bowden and a pair of pliers and a proper gauge spring wire for the actuator. I have actually replaced those a few times when I was working on them, since I made them too short the first time around and the resulting curvature was too tight. It took about 2 minutes to replace them.

     

  4. 29 minutes ago, Don Taylor said:

    Brilliant!  Simple and ingenious, using Bowden cables like this should be taken up by other makers.

    Thanks! It was one of those "how have I not thought about it sooner" moments. I don't mind others taking up on this, as I don't see myself in a concertina building career anytime soon. Maaaybee some 3d printed 46 button Haydens if I ever design a travel box for myself.

  5. 11 minutes ago, Dashy said:

    I actually came across it earlier today, it's really cool!

     

    I am curious about the acoustics, it sounds fine through video but acoustics is very hard. My brother and I actually have experience playing around with different materials and whatnot for some pretty involved 3D-printed headphones, PLA generally doesn't sound very good. Our best success was with PETG, and we haven't tried it yet but from my experience with other prints I think CF-filled materials are even better. Another material that comes to mind is woodfill (generally PLA-based), I'd love to try that with something like a concertina...

     

    Another consideration is the mechanical properties of the material. He says he uses PLA, which is generally fine, maybe a bit heavy but plenty stiff -just don't leave it in a hot car!

     

    As I wrote, Ed spent a whole year meticulously fine tuning the sound of it. Before he started making concertinas, he was an accordion tuner for more than a decade, so you can trust his expertise. But you don't have to rely on trust alone, he got some of the best UK players to "test drive" those. Also, the material of the concertina plays only a secondary role in the acoustics of it, sound reflections are the key.

    Now, on the unrelated topic, I have updated my thread with some pictures of the link mechanism: 

    As to sharing my handle design, my ultimate goal is indeed to popularise this design, so I don't say no, but you will have to be patient just for a little bit longer. At this moment those are calibrated for my hand only and the proper calibration is key to this design. I'll have to come up with some sort of adjustable solution first before I can offer it to the public.

    • Like 1
  6. Now on the second photo above one other feature can be seen - my air pad box. This is why it looks this way - my air lever. Because my "antlers" immobilise the thumb, I needed something different than a traditional air button. This can be operated by any of the four fingers and as such can be operated mid-phrase to close/open bellows faster. Though I only use it in one tune, because this beast have enormous air supply. Which points to a fun fact - with the bellows perfectly airtight, this box can play the lowest note, F2, continuously for 30 seconds. But because DIX reeds with the valves I use are so responsive and the bellows cross section is so large on this box, I actually had to introduce a controlled leak between the bellows and the reedpan to get a proper dynamic range for reeds above C4, because they were pretty much on-off with the slightest of the bellows move.

    The last update for now is my lap support. This ensures, that the LH side hand positioning stays absolute, as it eliminates any wobble around the vertical axis due to eccentricity of forces acting on the endplates on draw and anchores the LH side of the bellows. By the nature of my bellows (it is very rigid in both axis perpendicular to the bellows travel) it also stabilises the RH side, so this whole thing feels much more like playing on a static instrument like a piano rather than a concertina with a hand strap. It is a click-in mount, so there is only a little peg on the concertina itself. 

    air lever.jpg

    lap support.jpg

  7. Hopefully, this is my penultimate post before completion, as the box is fully playable for a few months now and only bellows papers left to do. Playability is in fact the reason why it is not done yet - I prefer playing on her in my precious little time I can spare for concertina.

     

    So, to the point. In another thread I've mentioned, that I've solved the links problem. My first prototype link all those years ago involved traditional levers, but it has proven impossible to route direct levers through the array and routing them around required so many intermediaries, that there was just too much loss of travel and response. And then occurred to me, that I could go through the inside of the box for a direct route and this is how I did it. Those are for Ebs, and if I knew this will be my solution I would arrange a few reeds differently to accommodate Abs also (at this point I could readily make one Ab link, but I don't see the musical point of just one). Bowden setup has all the advantages I can think of - it is smooth, PTFE tube+spring wire have virtually no friction, so no additional spring is needed; button travel is exactly the same, because lever arm length is the sam for both buttons; and with my button-to-lever connection design, the "donor" button does not move when the receiving button is pressed; and last but not least, there are no meaningful button force differences, so linked buttons work pretty much exactly the same as the rest of the array. With careful planning of the reed placement, I could get full range of enharmonic duplicates this way. I guess this is a "to do" for my future full piano range box, somewhere in the next two decades :D

    link bowdens.jpg

    links and air pad box.jpg

    • Like 4
  8. 18 minutes ago, David Barnert said:

    Have you seen this?

     

     

     

    I can wholeheartedly recommend Ed as a maker. I was a close witness to his journey from the early prototype to production models and as an accordion player himself, he is very focused on the sound of his designs as much as he is on the ergonomy of them. He is currently working on duets, Crane to be precise and is open to designing other systems as well, but not one-and-done projects, so it's more probable to get a standard 46 button Hayden from him than a 66 button one.

  9. Welcome to the fascinating world of solving Hayden range puzzle :D

    I went through the same process when deciding on what I want to have on my 66 button instrument all those years ago (self built, currently just bellows papers left to make and it'll be finally done, after 8 years). So you already know that overlap is important, but what you don't know is that reeds below C3 are way larger (about twice the area or even larger, I'm talking about a hybrid, so accordion reeds) than those from C3 upwards and require even larger chambers. You have eight of them, I have "just" five, two of which are long scale (so about 150% the size of normal scale). And by "larger chambers" I mean 150-250% of the volume relative to the reed tongue length than reeds from C3 upwards. My instrument is 8 2/3" and I could only make it about 1/3", maybe 1/2" smaller without sacrificing response and timbre. And I use linked buttons for 4 notes, so I'm talking about "only" 62 reeds... This is why duet concertinas have more notes on the RH side than on the LH side. It is LH that dictates the physical size of the instrument, and then you fill RH size with as many useful notes as you can route the levers to. Which leads to the second most important restriction - the problem of routing levers, which is a can of worms in its own respect. My concertina has handles a bit too much to the back, so the bellows works just a bit to off-center, all this because I wanted it to have a RH range from F3 to E6, so had to fit two rows of high reeds in front of the array.


    Now another problem with theorising the layout - concertina is not a piano, you have to reach all those buttons with your wrist pretty much immobilised if you go with a traditional hand strap design. It took me quite a lot of work to come up with a solution that frees the wrist, but it is highly unorthodox. You can see it here: 

    Another problem with sharps heavy array is that it inherently pinky heavy array on the RH side, which adds to the hand straps problem. So before you decide on the layout make physical mockup, including handles, and check if you are even able to reach all those buttons in practical ways.

    Now last but not least, to my knowledge no modern maker except me (and I'm not a professional) uses linked buttons because it is a non-trivial problem on a concertina. So you can forget about all those Abs, Eds and A#s without adding duplicate reeds and more layer routing/box size problems.

    To sum up - with your layout you are already approaching bandoneon sized instrument (because of bass notes), so you might be better with this: https://bandoneon-maker.com/professional-model-c-b-and-russian-b-system-bandonion/

    Or if you stick to the concertina, with this bass side, you can afford all the reeds you want on the RH side, probably another 10-15, especially if you extend towards "dog whistles".

    Ah, and I do use E6 and D#6 in at least one tune each, so I wouldn't drop them.

  10. On 1/21/2022 at 1:57 PM, hjcjones said:

    If I were starting again, I would seriously consider a duet.  However (not having seriously tried to play one) I wonder how intuitive it is to play?  Forming chords on anglo is very straightforward (in the home keys anyway) even with no knowledge of music theory.  On the other hand, I think of chords as shapes rather than notes, and find them on the anglo by poking about until something sounds right, so I'd probably work it out.

     

     

    On 1/21/2022 at 4:42 PM, David Barnert said:

     

    In a word, very. I can only speak about the Hayden duet system. Thirty-six years ago, Rich Morse put one in my hands and out came a tune. I had previously played many other instruments but no squeezeboxes.

     

    It's something that baffled me since my first contact with an Anglo, and then was further emphasised when I switched to Hayden - the claim that chords on an Anglo are straightforward. Generally speaking, they aren't, only those few in home keys are. On the other hand, chords on a Hayden are pretty much more fundamental to the layout than melody is. If you know the shape of the chord class, then you can play all chords of this class. For vast majority of tunes out there, you only have to know how maj an min chord looks like (other triads are just as simple). This is true as long as you don't have to wrap around the keyboard edge. When I got my CC Elise, I've been able to play all sorts of songs from guitar tabs in just couple of hours. This feature enables working on tunes (and understand music construction) from harmony structure towards the melody line instead of harmonising melodies - this is yet another perk of a Hayden layout, that it actually teaches music theory. Not only because it is isomorphic, but most importantly, it groups black and white piano keys together and is structured around diatonic scales and maj/min music theory. This means, that you can directly see which chords belong to any given key and why, which notes play what role in any key etc. It is all there in the button array itself. 

  11. On 1/13/2022 at 4:49 PM, Stefan said:

    There are two small microphones under my palms, one left one right. They go into a guitar multi effect board that has two separate effect strings. So I can use different effects for the left and right side. 


    Thanks! But I do wonder - how are there no feedback loop problems? Sorry to ask so many questions, but I simply love the electrified concertina sound since I first heard your recordings few years ago, and wanted to try this myself, but I have no real experience outside of acoustic and MIDI environments.

  12. 59 minutes ago, Stefan said:

    Yes Geoff, it´s from 1916 and I am still greatful that you gave it to me. It plays and sounds like a dream. And yes, I take good care of it.

    Do you know where Alex West got it from? He is a member here, maybe I can ask him.

    If Concertinas could talk....

     

    I always wanted to ask you - how is it electrified? Is it a pickup, a microphone, a MIDI pickup? And do I guess correctly, that only a single side is electrified and the other is plain acoustic?

  13. 7 hours ago, Little John said:

    I envy your opportunity to try this out. I'm sure I would find it fascinating, but in the end I have to go with your later sentiment:

    but if I had come across it much earlier I would have been sorely tempted to make the change!

     

    I don't really think about it now, but in my earlier days I tended to think of it as right-to-left: D E F (up a row) G A B etc.

     

    I also wondered why the original design wasn't right-to-left: C D E (up a row) F G A etc.; ie why the "D" and "E" columns are interchanged to give the 1-3-2 pattern of fingering. My conclusion lay in the right hand accidental column. If you think of them as being related to the adjacent column then the CDE pattern would yield Eb, Ab, Db, Gb and Cbb (yes, C double flat). The actual CED pattern gives D#, G#, C#, F# and Bb which is much more intuitive.

     

    I actually played a mouth-blown version of this once. The keys were hexagonal so there were no gaps. However following the link and studying the layout makes it clear that you couldn't convert a Crane as even a single chromatic octave takes 7 columns.

    Ah, you’re right. I just remembered it exists, scanned through it briefly on musix when posting and my phone cut it to five chromaticized columns. My bad. I have clearly overdosed isomorphic layouts into one, big, isomorphic blur :D

  14. For those of you who would like to dabble with this or other regular layouts, there’s a great app called Musix, that let you arrange any isomorphic layout on either square or hex grid. 
     

    As to features of 5CC, any isomorphic layout gives you uniform triangles for triads, and in fact a single geometrical shape for all chord classes. But some of them strongly favour chordal play vs melody play, some get into „twisted fingers” problems, some have octaves stretched over so many columns/rows, that it is impractical or straigth impossible to implement on concertina… 

     

    The layout that seems to be best suited for Crane conversions is called Harmonic, spans over 5 columns of the hex layout and is pretty much a Crane turned inside out - black buttons in the center, white keys on the outside. It’s main feature is that with large enough buttons and small enough distances between buttons, triads can be played with a single finger. Great for singing accompaniment Cranes are often used for.

  15. I’m 100% positive, that they mean brass plate, steel tongue, and probably mean DIX range of reeds by Harmonikas.cz. The reason is very different tone, way closer to traditional concertina reeds, than standard accordion aluminium plate reeds. In last years harmonikas.cz extended their DIX range towards concertina world and now offer three grades of reeds suited for concertinas - fully traditional with straight screwed tongue; semitraditional with standard accordion shaped tongue on concertina shaped shoe; and their brass plated twin tongue accordion reeds. I have those reeds in my Hayden and they sound lovely. They have way more depth to their tone than standard accordion reeds.

  16. 4 hours ago, ttonon said:

    Lukasz, from my calculations, I see no possible resonance interference with the tongue vibration.  This applies to both Helmholtz and quarter-wave tube resonance.  

     

    I thus cannot make a suggestion here, only I'm still not clear on what the basic problem is.  Are you saying that all the F3 reeds you put into the "bad" cavity show the same problem?  Also, that when you put those same reeds into a different cavity but with the same dimensions of the "bad" cavity, there is no problem?  

     

    Best regards,

    Tom


    Exactly. Bad cavities are on the LH side of the instrument and good ones are on the RH, reeds are identical and it does not matter which one I mount where. The .wav file above is with endplates mounted, but this problem is present without the endplates as well. Endplates emphasise it further.
     

    Some parameter of reedpan is causing this but not simply inner vs outer chamber placement, as both initial chambers are outer ones. I suspect it is either amount of solid wood block left in the reedpan, differences in reedpan’s wood parameters between sides or the exact layout of surrounding voids, because I can get significant improvement in spectrum shape during tests by using tack to mount the reed to the reedpan instead of rigid screw connection and thus decoupling it mechanically. 
     

    But using tack is not a valid permanent solution so I’ve settled with increasing chamber depth to bring missing partial back as a way to rebelance this instrument. It is not ideal, as I loose some higher partials this way, but it sounds way smoother now.

     

    Perhaps it is now easier for you to understand why I said, that reeds seem to not care too much for our simplistic mathematical models :D 

  17. 2 hours ago, malcolm clapp said:

    In response to a couple of recent inquiries, I have today posted on my Soundcloud page https://soundcloud.com/klappo a number of recordings I made back in 1984 of talented Crane/Triumph player Polly Garland, who sadly passed away at the end of last year. (Just ignore my melodeon stuff 😎 ). Perhaps Daniel or Alan might like to add a link or two to the Duet Recordings Page if any of the tracks are likely to be of interest to members here. Thanks.

     

     

     

     

    Great material! Does anyone know, by chance, where can I get the dots for "Un-noticed Waltz"? 

     

  18. 1 hour ago, ttonon said:

    Hi Lukasz, I just now heard your wav file and I agree, the 1st and 3rd sounds seem restricted, and the 2nd and 4th more open or free.  In my experience, such a restricted sound occurs when the mounting of the reed - most often the geometry of the cavity - begins to acoustically interfere with tongue vibration.  For instance, if the port is too small, or even if the leather valve isn't opening completely enough.  Alternatively, there could be some defect in the construction of the reed, such as a burr, or other way to interfere with tongue vibration.  

     

    Your guess that the problem lies in a restricted second partial seems to be borne out by the spectrum.  In the bad note, that partial is about 13 dB below the fundamental, and in the good note, it's only about 5 dB below the fundamental.  I'm not sure there's evidence in the spectrum for your claim that the energy of that second partial is fed into the higher partials, which from my experience would be an odd occurrence, knowing what I know about the conversion of pressure pulses to audible sound. 

     

    We can notice that the bad note has also a greatly reduced 8th partial, compared to that of the good note, but I doubt that has anything to do with what we hear, since the pitch of that partial is about 22,000 Hz, far above our normal hearing range.

     

    However, your discovery of this reduced second partial may give us a clue.  If you'd go through the trouble of presenting here all the exact 3-D dimensions of the cavity and the size of the port, I'd be glad to take a look at it, possibly finding an identification of the second partial frequency with some way the cavity could resonate.  If it's a simple rectangular cavity, it should be easy to do.  

     

    Best regards,

    Tom 

     

     

     

     

     

     

    That's exactly the mystery though - ALL tested cavities (this is a hybrid, I have more than two cavities of same dimensions), good and bad are 39mm x 14mm x 10mm and ports are 10mm diameter (and I also tested it with 12mm, 9mm, 8mm and 7mm ports). Graphs you see above are identical if I switch the reeds side to side or if I test any other identical chamber on the LH. I have two reeds (four tongues, four valves) and the problem always stays with LH side of the instrument for F3 note, with or without endplates, in both airflow directions and with all possible flips and orientations of those four tongues. Some of those chambers identical chambers are outer (basic two in question are both outer, but one of them is perpendicular to the closest outer edge and one is at 45 degrees) others are more or less inside the reedpan.

     

    Regarding "feeding into higher partials" - audible volume of the bad reed is louder than the good one (though dB meter stays at +/- 1dB spread between sides), so I figured that this energy has to go somewhere and on those graphs you have bit different distribution of dB levels of higher partials. You're the expert though, I'm just a more and more confused amateur builder looking for solution even more than the cause.

     

    Now the trick with increasing depth of the bad side chamber by 50% does change the spectrum enough for those notes to blend into the accompaniment well enough to pass as a flavour instead of the right out interruption, but this is a not ideal workaround.

     

     

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