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Dana Johnson

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    Playing ITM and making concertinas
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    Kensington Maryland. USA

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  1. Whatever you do, make sure it (and you ) can survive a spill. I’m not a big fan of soft cases. I know a lot of people use them. They are fine until they aren’t…
  2. Hi Tom, I am not sure what different air oscillation modes a chamber can provide, and I am pretty sure hemholtz resonator is one, like the main body resonance of a violin box, as well as a back and forth sloshing mode where the the pressure alternates ends of the box without air entering or leaving the “f” holes. There is also the question of how the reed itself alters the hemholtz frequency. Calculations for ideal resonators must have to be modified when for instance, the chamber has flexible walls ( lowering the frequency. ) Your experience of the reed being killed when the resonator matches the fundamental (or any strong harmonic ) is what I expected. You are right about being able to alter a balky reed’s chamber to get it going properly. On My Wheatstone Layout G/D there is a pad that opens onto a chamber with 2 reeds that are of substantially dissimilar lengths. I found the small one of the reed pair was much quieter than it should have been compared to reeds of similar pitch in other chambers. I split the chamber into 2 sections and the reed immediately was at its proper response and volume. Note that the drastic change in chamber volume had no noticeable effect on the either reed’s tone compared with other reeds at those pitches with full width chambers. ( the reed in the short side is a press reed so is not visible. The split chamber allowed me to dispense with the valve for this small reed where without the partition, it needed one. This idea of resonances interfering with the reed vibration is something I have generalized, with absolutely no proof, to the notion that the body of the concertina behaves like a filter, suppressing or reducing the various components of the reed’s spectrum. Hopefully you will be able to get as close as possible to an isolated reed without the complications of chamber volume. You might need a good anechoic ? chamber to do your tests in because normal rooms can have a surprising number of resonances that can cause trouble. If you need other reeds, I’ll be glad to help if I can. Best Wishes, Dana
  3. I make Wheatstone style bellows where the binding goes on last, I skive my runs down to zero at the edges over about 6 mm of width. With the binding being 18mm total. Coupled with the opposite shive on the edges of the leather butterflies, (leather, not papers ) this leaves a pretty level surface. Where the skived surfaces overlap. For the rounded corners, I cut the ends of the pleats on a shallow angle leaving a v shaped notch at each peak end. The angles are such that combined, they form a segmented arc. The split at the ends comes together when I put the gussets on and fold a little skived excess over the top. Once the gussets are on, the bellows is air tight, and the binding only serves as protection and a cover for the card edge which I also cut with s 45 degree mat cutter so the card thickness at the peak is zero, helping to reduce the need for the leather to stretch when the bellows is closed. The wider your binding strips, the more material on the side you have to try to smooth out, so don’t think wider is better. When I wrap my binding, I use a bit of wet sponge to wet the binding a bit where it goes around the corner. That lets that portion of the leather stretch there only while allowing you to put more tension on the strip ahead of the corner. This helps since your strips cut parallel to the spine are goat’s least stretchy direction (belly skin excepted) , leaving its natural stretch across the peaks where it helps to reduce the bellows stiffness. The wet at the corners allows just that part to stretch, pulling down the edges at the corners nicely with little or nothing to smooth out. Dana
  4. Tom, I don’t consider a reed that fails to speak due to chamber length mismatch, “choking”, what I experience as choking comes from a reed that speaks fine at lower pressure, but stops abruptly if the pressure passes a certain point. I experience this in two cases. First is when the reed is set too low, which may decrease the starting pressure ( seemingly a good thing but limits you to quiet playing ). Second is when the reed is weak for its length ( incorrectly profiled in the neutral area ). These reeds will choke regardless of set. I wonder about the hemholtz resonator analogy. I am not sure how this works since the chamber is open at both ends, though one end changes as the reed moves. Is resonance the only characteristic a chamber can have? Also, in the G1 chart, the bold numbers are for the 15th harmonic which is going to be vanishingly small, and I have a hard time seeing that as killing the vibration. I wonder if electrical analogies like capacitors and inductors might be in play, since both the reed and chamber can be energy storage /modulating devices. , and not necessarily as a tuned L/C circuit. Maybe a power factor phase shift ? In my experience, varying the height of chamber walls affects the proportions of the harmonic spectrum , with shallow chambers favoring higher harmonics over fundamentals. Length did not affect this noticeably. ‘even .032 inches in height difference is very noticeable in tone difference.
  5. Lukasz, especially for lower reeds (B3 and lower) and especially if the press and draw reeds are close in pitch, ( and or have a harmonic component near the paired reed ) I often experience an odd coupling where the flap valve adjacent to the active reed slightly opens and closes causing a burr adding to the reed pitch. This also happens at low to medium pressure when the valve is cupped ( touching at tip but not in center ) even for high reeds, where it opens and closes with the pressure variation, making the burr related in frequency to the active reed. I can usually solve the low reed condition by using a valve that is thicker but not stiffer so it has a lower ability to vibrate at the activating pitch. The noise isn’t valve noise, but rather how the driving pressure on the active reed is caused to vary by the slight bypass of the vibrating valve. I don’t know if this will help your particular case. Dana
  6. I have similar experience to Lukasz, though the longest reed I make is G2. I have also found reeds around C6 and above can actually go sharp at the higher practical pressures. Here, I haven’t seen more than +5 cents. Lower notes are more affected, and quite audibly so, enough to be made part of technique. Here, I do find that press works too like draw, but you have to mean it. When tuning, I find it important to keep pressure constant since it easily affects reeds in the 3-5 cent range at normal playing pressure The big thing Lukasz mentions is the effect of chamber length as its proportion to reed length varies at different pitches, and the pad hole size in conjunction. On a C/G Anglo, I use 4 different hole sizes. ( 5 on a G/D ) because not only can a too small pad hole flatten the note, but it also causes a tone change where higher harmonics are reduced. Wheatstone Linotas I’ve seen have relatively small pad holes and the tone change from exertion while playing is something I’ve heard Noel Hill use for effect. there seems to be a best size for different pitches, though it probably interacts with chamber length, so may not be transferable from one chamber layout to a different one. I originally used one size for everything, but found by progressively reducing the diameter, I reached a point where smaller would actually make the note sound clearer, but still be large enough to prevent the tone change at high pressures. I used that break point to size all the holes. The Wheatstone Duet I used to own had equivalent pad hole scaling (and chamber length scaling ). I do not understand how chambers and tone holes work, but a low reed un an undersized chamber may not operate at all. My tuning block has a series of separate chambers sized for pitch ranges. I switch chambers when a reed starts to be balky or not speak well at a particular chamber. The effect of the chambers / pad holes is large, and trying to tune a reed in an environment where it is clearly getting damped compared to a reed that goes well with the chamber can easily mean 10 cents off what it should be. I use little rubber sheets to cover the tuning ports not in use, and can have a balky reed sound good again by partially opening an unused port. Since I tune at a constant pressure, I am guessing that opening the free port, changes something in the acoustics. The chambers all share a common plenum and all have the larger pad holes emptying into it. one thing I wonder about is the way air moves into or out of pad holes. Air going into a hole looks like water going down a large drain, coming in from the sides as much as above, while air leaving a hole is more jet like. the proximity of the pad to the hole may cause different effects on the press vs the draw because of the relative obstruction of airflow. one last thing, poorly centered reeds are much more vulnerable to flattening audibly as pressure rises, as is a weak (thin ) reed for the given pitch. Sorry not to have a lot of hard data, but given how interactive things seem, it would be easy to misattribute any particular effect. You are going to have to build your own setup where you have more control than I do, where I try to find what gets the results I want without trying to figure out why. Best Wishes, ‘Dana
  7. After tuning 6000 reeds, I am inclined to agree with Alex, with the exception being that the flattening on raising or sharpening on reducing the set depends a lot on the length of the reed, with longer reeds being less affected than small reeds. I re set a G6 reed on a friends concertina that was set ( probably at the factory ) so high it took a ton of pressure to sound at all. When set to the proper height where it responded quite well, it was 20 cents sharper and needed to be retuned. In most cases for reeds that are responsive, I generally don’t see more than a couple cents variation. I always check the set before any tuning and often find that returning a reed to its proper height is often all that is needed. Given the number of things that can affect pitch, the reed isn’t always the culprit.
  8. High humidity causes less problem than low, but your description is a common one. The reed pans can absorb a few grams of moisture, which will change the interaction with the reeds in a noticeable way. The valves also take up moisture and can lift slightly as the lower layer of the leather expands more than the upper. This can lower response as the valves take longer to close. Nothing to worry about, Dessicants get used up quite quickly and need to be restored by heating in an oven, though most packs I’ve seen aren’t packed to be reused. Unless your case is airtight, the “partial pressure of gasses” will always seek to equalize the humidity between the case and free air. Dehumidifiers are more constant, but use a lot of electricity and still need to be in a closed room. The good thing is that wood loses moisture at a much higher rate than it takes it up. Days vs hours. So it does little damage. The best thing to do is play the thing, which can free up sluggish bits and help them find a stable position. Dana
  9. Hi David, It has been a really long time since I had that duet, but it’s low note was the same as the low note on the 67 button McCann. The right side went down to C4 originally but because of the music I wanted to play, I added notes town to G3. That made for a very full reed pan. Even in that large format, I couldn’t have added extra notes unless they were inboard. The lever arrangement was difficult enough with all those notes. It used all long scale reeds, so going short on the lower notes would help with the relative volume. If you will remember it was originally the same model as that Wheatstone McCann that that fellow with the operatic baritone voice who played McCann at the early NESI years had. His name escapes me. That thing could roar!. (And so could he) For other makers, that Duet had tilted reed pans so the highest notes had shallower chambers and the lowest were deeper. Both sides were like this, but on a more limited range would be less necessary. It did mean that you had less flexibility with reed placement when thinking about lever patterns, but it was important.
  10. I don’t know if you would consider it a deal breaker, but below G3 reeds get bigger fast. Not only that but the chambers need to increase in length over and above what the reed frame would need in order to respond well. For low reeds this means chambers that take up a lot of space. Weight will be more the result of the larger overall size instrument needed to accommodate the larger reed/chamber space on both ends, rather than the weight of the bigger reeds. 30 years ago I converted a Wheatstone 67 button McCann into a 63 button Hayden. The right side was similar to yours except for having a C6 and D6 on the top row, but the left only went down to C2. This was a large instrument, something around 9 inches across the flats, and believe me, there was no extra room. It didn’t include your F#2 or G#2 on the left hand lowest row. The other issue is volume balance. On extended range instruments, the lower notes are much louder than the higher ones which is ok for melody where you can vary your playing pressure to suit the note, but playing left and right together can be a problem since one bellows pressure applies to all the reeds being played. Wheatstone tried with only small success to quiet the left hand by having a much smaller fretwork on the end with the pads being covered by solid surface of the end plate. Lastly and least important, on equal tempered instruments the only difference between D# and Eb is what you choose to label them. Sharps and flats are musical conventions telling you where a note is relative to the home key. The distinction does matter in other temperaments where the “ideal” ratios to the home note are the goal. One of the beauties of the Hayden is the ability to maintain fingering between any key which is asking for equal temperament unless you want to restrict yourself to only a few keys. Dana
  11. Especially if you want to play the genres you mention, having more key flexibility is a must. 30 buttons are fully chromatic for most of their range, but getting fluent in a number of keys will require diligent practice. However, if you organize your practice around that goal, it will become much more natural as you get to associate certain pitches with their buttons ‘ direction. One good exercise is to play something in your normal key, then one whole note up on through some sequential keys. You can do half steps too. Remember, you still have to place the music in the instrument’s range. That means if you find a tune goes too high, play it an octave lower etc. likewise if it goes below the chromatic range, you may need to try it an octave higher. A lot of tunes are in the keys they are commonly played in because they were composed on instruments of a specific limited range. Remember, you will have a number of buttons that play the same note, sometimes in different directions. Try using alternates to find the best to use for each key. Lastly, learn some pieces that are a challenge and need the chromatic scale. I like JS Bach partitas for solo violin since the range is about right for a C/G 30 button. You might need to transpose the music to fit the notes you have available. Even if you don’t master them, they will improve your ability to find notes when you need them. Oh yes, even if you read music Jams/sessions are aural things. You need to be able to hear a note and then play it. Whatever you do, make it fun! Dana
  12. Having 2 mics pointed at each end seems logical, but unless they are quite close, or you are in a fairly well acoustically damped room (or outdoors ) the distance between the mics can cause very noticeable comb filtering, as both mics pick up sound from the other side slightly later than the closer mic. ( causing interference of sound waves that happen at frequency multiples of the separation distance 1x2x3x etc.) Center location in front keeps things equal and having a coaxial x/y mic preserves the stereo aspect without comb filtering. Listening through headphones connected to the mixer or monitor lets you hear what other people are hearing or you are actually recording. Without them, you are not likely to hear what is happening at the mics. Even good mics can be blamed for poor fidelity that really is the result of comb filtering.
  13. I am really not sure, but I’d guess the point of the “ Anglo system “ was being able to increase the number of notes available in a workable size. Reeds are the most expensive part of a concertina and having each button/reed chamber play 2 different notes rather than one substantially increases what you can pack in a small package. A 48 button treble English has 96 reeds while a 30 button c/g Anglo covering a slightly larger range only has 60 reeds. Diatonic free reed instruments have been around for quite awhile, and I expect that their adoption in folk music was driven by low price first and that playing styles evolved to turn it’s restrictions into advantages. The common Anglo with a center row in one key and the inner row a 5th higher, does have rows that make playing in those key easily accessible to beginners. But that layout generates many duplicates in either the same direction or the opposite. This allows you to choose how to play a certain passage or organize your scales to provide better bellows control, ease of fingering, or my favorite, phrasing. Having a “go to” basic scale fingering to start with be it cross row or along the row, gets you up and running, but it is important to get fluent in using the alternate buttons to make the most of the instrument. There are hoards of tunes I play that I will use one button in the first go round of the A part, but use the opposite direction note the second part around because the ending note of the first time through phrases better with a different direction note to repeat. Getting used to using alternates when they improve the music and being able to swap them out on the fly depending on your mood in the tune really can improve your playing. Using alternates when looking for a particular harmony is a great thing to explore, and you shouldn’t consider any basic fingering as more than a starting point. The instrument is remarkably versatile and working out how to best express the music is the path toward real musicianship.
  14. When I was a kid, I was told that you only used the stalks of the rhubarb not the green leaves because that is where the oxalic acid was. ( Checked in the encyclopedia )Many plants use this sort of distribution to discourage critters from eating the leaves. The stalks below the leaf have little if any oxalic acid. Potatoes are similar in that the potato is fine unless very green from light exposure, but the rest of the plant including the fruit contain solanine, a toxic alkaloid. Sometimes it is the other way round as I discovered when our young dog discovered the bulbs of some of our hyacinths were great fun to mouth and toss around. This time toxic to critters underground. We had to dig them all up☹️
  15. When The Button Box first started making the Ceili, Rich seriously considered adding weights to it because compared to other concertinas, it was so light. Just as well they decided to see how people liked it. The rest, as they say, is history. Dana
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