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Dana Johnson

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Everything posted by Dana Johnson

  1. 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.
  2. 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.
  3. 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☹️
  4. 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
  5. Even though 20 button’s only completely cover the 2 major keys and their relative minors (Amin and E min for a c/g), you can still play a lot of tunes in D for instance which is only missing the c#. Some tunes really can’t do without that note, but for many others, you can simply hold the previous note or substitute an ornament or chord for the duration of the c#. In Irish trad music, there are a lot of D tunes that leave out the C# presumably because they were composed on instruments that are like harps without sharping levers or one row melodions. Some great players like Jacqueline McCarthy played on 2 row C/Gs. Also, and I expect for similar reasons, Irish music is full of tunes that are “modal” and sound like they should be in D, but partake in the key of C (one whole tone down ) when a C# isn’t available. This mode is so much a part of ITM, that you won’t ever run out of “D”tunes. The same thing holds for many modal A tunes that oscillate between A and G scales. 20 buttons may be more limited than a 30 button instrument, but not as much as you might think.
  6. 2 more little things. Lower reeds that are thin (and don’t have enough strength) may respond well, but are more subject to choking and also blowing flat under pressure. Badly centered reeds also blow flat more easily than well centered ones. Reeds need to develop enough spring force to return effectively against the playing pressure. In instruments like large duets, baritone and tenor Englishs need longer reeds in the mid range to compete in loudness with the naturally large, long and loud lower reeds, so the scale for baritone or tenor may be longer for the same pitches than a treble instrument. Making the already slow low reeds thick heavy tipped to lower their pitch will make them respond poorly, so compromises need to be found elsewhere.
  7. It is very possible to make two reeds of substantially different lengths that are still the same pitch. At the high end say C6, shortening reeds makes a big difference in pitch, so reeds that, as a practical matter, work as they should, end up very close to the same size. However lowering pitch by adding length creates reeds that in the lower notes C3 etc. get long fast and take up more room. In order to keep lower reeds a workable size in a concertina where space is at a premium, shorter lower reeds are chosen and then weighted near the tip either by grinding the reed to be thick at the tip, and or adding solder or a bit of brass to the tip making them heavier and slower to vibrate. The more this needs to be done, the worse the reed’s response. By varying the scaling of the reeds ( the scale factor of length from one reed to the next in pitch ) reeds can be made to fit in a limited space. “Long Scale” reeds are made as long as practical in the low end and generally will be longer pitch for pitch than instruments that needed shorter reeds in the low end. Reed length and width do have an effect on tone, but a lot of other factors do too so it is hard to generalize about causes. Within practical parameters though making a reed longer with a thinner tip will make a more responsive reed. Regarding tone, the shorter chambers that go with shorter reeds have a noticeable effect on tone which may be interpreted as coming from the reed instead of its local environment. Low reeds are naturally slower to respond than higher reeds ( assuming a well made instrument). Optimizing low reed response is a very worthwhile goal since reeds need to equal the music they are asked to play. Dana
  8. It isn’t the number of posts, but the quality of them that counts🙂
  9. If the leather is actually white and not very light blue grey, it is probably alum tanned or tawed. It was commonly used in concertinas in the past and you’ll find many vintage concertinas of good quality that used it. It has the benefit of being quite springy for its thickness without being stiff or heavy. The big problem with it is that over time, it corrodes the brass of the reed shoes next to it. I discovered this on one of my instruments back for tuning after about 10 years and noticed the corrosion only on the reeds next to this kind of valve. Haven’t used it since. Here’s a pic of a Wheatstone tenor reed pan with the original white valves. You can see the corrosion primarily next to the valves, but spreading a bit from there.
  10. “My guess is that the curled up reeds prevent some of the high vacuum pressure from occurring inside the bellows by allowing some excess air flow through non-sounding reeds. This prevents too a vacuum pressure that would tend to choke the reeds that are intended to voice. If those reeds weren't so leaky in the first moments, perhaps the playing reeds would choke and not play at the right time. So we want maximum dynamics in volume, but don't want to choke the reeds.” In my experience, reeds that are set low enough to risk choking under either rapid pressure gradients or high pressure, are set too low to reach the amplitude they are capable of, though they may start at lower pressures. I don’t know if bandoneon makers use a different sort of reed plate window than is found in ordinary accordions. The pictures I have seen look like basic accordion construction except using single plates with a whole row of reeds on them. (More like a harmonica) The pictures I have seen had valves lying flat. Reeds that are very flexible for their pitch also can choke easily, but can’t reach the volume of a reed stiff enough not to choke at its optimal set. Allowing some bypass air can help avoid choking on a reed prone to it. Noel Hill once mentioned needing to slightly feather the air valve when playing a specific note on one of his instruments to avoid it choking. His playing can demand a lot from the reeds (and hand straps! ). On concertinas, a valve that is curled a bit or just bent high, significantly affects the speed of response, as well as causing a noticeable increase in volume as soon as the valve closes. High set reeds can also be slow to start, but the slight delay and abrupt increase in volume shortly after the reed sounds, is a dead giveaway for a raised or curling valve. Dana
  11. There are a lot of tunes in ITM. That seem to have been built for along the rows playing. I figure perhaps they came from the melodion players. They organize themselves beautifully around the push pull nature of that kind of playing, matching good phrasing and rhythm, as opposed to other tunes that chafe at being forced into that restriction. C/G’s are very versatile given their pitch range which is similar to a fiddle and covers all the notes typically found in the whole ITM repertoire. The common ITM keys are very easily learned on a C/G.
  12. In old leather what people call drying is often degradation caused by decomposition of tanning chemicals left in the leather as well as absorption from atmospheric pollution especially from coal burning and similar high sulphur fuels. The same stuff in the air that tarnishes silver does a job on leather over the years, weakening the fibers to the point of breaking. Some tanning methods produce leathers that last centuries, but the modern age and chemical revolution weren’t much concerned about longevity, book binders were, but for most other people, price was the important feature. Recently actual “archival” leathers are becoming more available.
  13. The software company that administered the contact page of my website seems to have gone out of business, so I replaced their form with an image of my business email to avoid bots and spam. I am sorry you’ll have to copy it down by hand since it isn’t text or a link. To those who have wondered, I am still happily making concertinas. I recently had to increase my prices to cover having to cope with CNC software and hardware that was no longer supported on the new operating systems. Gone are the days where you could buy something once and have it work for a lifetime. File migration is a real headache. At least concertinas still have longer lives than we do. Dana Johnson Kensington Concertinas
  14. Spring wire like any wire will return to its original shape unless bent past its elastic limit. Beyond that point it will not return all the way. The wire isn’t damaged at this point. Bending beyond a certain amount will start to create tension and compression failures which do weaken the wire. Coils that are too small for the wire diameter will do this and you can see it under the microscope. Annealing lowers the elastic limit, work hardening increases it. Spring wire needs a high elastic limit to be useful. In this context, “right” is dependent on the alloy and its properties after drawing. As long as the spring wire is not bent to the point of initial failure, you can use the new shape as a starting point. The only way for you to check this is to try it out and see if your newly stretched spring retains its shape when you use it. The actual force the spring can exert or resist, depends on how much it is flexed in use, the wire diameter, and its length. Coil springs turn long wires into short spaces, so for a given pitch, adding coils = adding length and making that spring less forceful for a given deflection. If you want a stronger spring, you can reduce the coils, make the wire thicker, or make the coils smaller so they don’t contain as much wire. Conical springs are very handy for compression, since they can be squashed flat since the coils nest. You may find that the wire you got from Juergen just isn’t thick enough for your type of spring. Going up a gage or two is something to try. One other thing, tension springs are generally wound with a negative degree of pitch which makes the coils very tight to each other, pre loading them. By stretching these springs, you both add new deflection, and overcome the negative deflection that is built in for a total deflection that is larger than it appears. Sorry if this is a bit confusing. There are a lot of resources on the web for spring design info. Dana
  15. Generally hardenable steels are heated above their normalizing temperature (alloy dependent, but generally above well above 1200 degrees F) then quenched or quick cooled to lock the steel into a hard crystal structure, then reheated to a lower temperature to draw out some of the hardness to make it useful for something other than a file. Spring steel wire is annealed as thick rolled wire, then drawn out which hardens it. If it needs to be drawn out very thin, it may undergo a number of annealing stages between drawing through dies which makes it hard again. 300 series stainless steel can only be work hardened. But for practical purposes, all spring wire is work hardened by drawing through dies. Trying to re-temper a spring first has to go through the normalizing temp. Quick cooled, then reheated to the correct tempering temp again. None of this is a very practical thing to do since it would need to be done in an inert atmosphere among other issues. By choosing the right diameter wire, you can stretch out a tight spring and have it work, but you need the wire size that is strong enough to give you the right result. Stretching a spring doesn’t deform the wire any differently than winding it does. It is just bending the wire in a different direction. Dana
  16. Box players generally do the opposite and manage ok. You should be fine as long as you don’t rotate your torso any more than needed. Doing a few opposite twist stretches after playing should help keep your muscles balanced. Stay aware of your body. Dana
  17. Re plastic valves, advantage, predictability and stability, but compared to valve leathers, plastics are both dense and stiff. 1 mil Mylar might work for very small reeds, but 2 mil is 2x as thick and since stiffness increases very fast with thickness, even though you can buy it in 3, 4, and 5 mill everything gets way too stiff compared to proper leather valves of the right length. You’d need .001, .0012. .0014 etc. to give you workable gradations. I keep thinking there must be a good way to use the stuff, but I haven’t found it yet. Leather has the advantage of working well for years when it is the right leather, thickness and stiffness. Single thicknesses can cover a number of reed sizes and .020” and .025” -.035” gives a large range with only gradual changes, making finding the right valve easier to find/make. It is hard to find a more perfect material than the right leather, but it isn’t always easy to find. Dana
  18. 25 years ago I took an old Wheatstone McCann and converted it to a Hayden back when that was pretty much the only way to get one. Don’t regret it at all. Not a small job though. These days it is almost less work to start from scratch. Dana
  19. As you say, the opposite reed valve closing is what is going on. Under ideal circumstances the valve will lay flat in the closed position as soon as that reed is no longer sounded. Quick note reversals will accelerate the closing but in that case, the newly sounding reed will start at nearly the same instant and cover up any slap. It is common for valves at rest to be above the port, and will close once pressure is high enough. This is out of sync with the reed and can be heard both as a slap and an abrupt increase in reed volume when the valve closes. Changes in the weather can cause the upper surface of the valve to shrink more than the lower surface causing the valve to curve up. Valves applied flat under high humidity conditions can raise a bit in a new drier home. A concertina stored on it’s end will cause the underside valves of both ends eventually to curl away (these need replacing ). For valves that are simply resting a bit high, you can usually get away with gently dragging the back of your fingernail over the valve from glued end to tip. This stretches the backside a little to allow the reed to lay flat again. This may work for a long time especially if the problem is not severe. Valves that stay significantly up after this need replacing. Harder valve leather makes more noise than leather with a softer underside, though a properly flat valve will still be nearly inaudible. The opposite problem occurs when the underside of the valve becomes the shorter surface, causing the valve to arch up in the center while touching at the tip. This can cause the adjacent reed in that chamber to sound rough or garbled and is most noticeable at lower volumes. This is caused by bypass air getting under the valve reducing the reed volume, but then the valve is sucked flat and the volume goes up. The acoustic pressure in the chamber varies enough so the valve lifts in the center again, then closes, repeating the cycle at some fractional value of the reed’s pitch. While most problematic on low reeds, I have found this all the way up to C6. In these cases, simply holding the valve down in the center and lifting the tip to bend it up a little, will cure the problem. On low reeds even a good flat valve can bobble up and down if it is too stiff, or too light. Finding the right valve weight and stiffness for these reeds is not so easy. I find proper valving one of the more difficult parts of making the instruments. Valves can make or break an instrument, and can be the cause of a range of problems that don’t initially seem related. Dana
  20. It is easy to call something by a name that has the connotation of quality. Fully machine made reeds need larger tolerances, since the punching process for both the windows and reed blanks produce very slight size differences that together can cause an interference fit if a tight window matches up with a wide reed. As such, if your punch sizing eliminates this problem, you have reeds that can go from a good fit to a very open fit from the same punch set. Hand finishing allows you to start with tighter fitting blanks and work to a tighter tolerance that can be more uniform from one reed to the next. I am not terribly familiar with that sort of reed making, beyond the various film clips I’ve seen, but I have seen reeds separated into sets that share similar characteristics to make sets that behave well together. Really good reeds will have more attention paid and by workers that specialize in making them. Price ranges within one company is probably a good indicator of what is good. Prices from middlemen maybe less so. I have seen really good accordion reeds and pretty bad ones too. They were easy to tell apart. Since reeds have a major part on how responsive a hybrid will be, go with reeds that show off your efforts. Dana
  21. One thing to keep in mind is that woods lose moisture to the air at a much higher rate than they regain it. This is especially true for thin wood like violin plates. In concertinas, the pad boards are generally one of the thinner parts, with the reed pans being next. The ends if wood, are commonly laminated and are less vulnerable. Room or house humidity control avoids the sharp changes of in case to out. In case humidifiers are a second best, but still worthwhile bit of insurance. I have used a large console evaporative humidifier for a long time for my shop to aim for that 50% rh level in winter with no white dust, they have their own problems, but don’t make a mess. Cooler temperatures reduce the need for extra humidity.
  22. Alex West, I used a US. Uddeholm distributor since that is where I live. Since they are a European company, you ought to be able to find a distributor on the company website. I was lucky to be able to buy a minimum order including different thicknesses, but still have a lifetime’s supply I have been sharing with a friend. The Sandvik version sounds a reasonable choice too. I have been using (small ) 18-8 stainless nuts and bolts for the past 25 years dry with zero problems. If you don’t have to tap anything, I’d say stick with the best corrosion resistance alloy. That is the only place galling might occur in tight or over torqued threads.
  23. Don is quite right, though the strap is more to keep the bellows from opening up somewhat on it’s own and needing more pressure on the press notes when nearing more closed than the resting state. A hard case with corner blocks eliminates the need for a strap and provides vastly more protection to your possibly expensive instrument. You aren’t likely to over-stress the bellows taking it out of the bag unless the bag is too small. If you haven’t bought the concertina yet, spring for a hard case with it. If the cost of the case is a good portion of the price, you are likely to want a better instrument soon anyway, so you can start squirreling away money for a case worthy instrument. Dana
  24. Chris mentions stainless on stainless as being prone to galling, but as always the alloy counts. 300 series stainless should not be used together with itself or others of the same series. The nickel content is the culprit and on a molecular level will jump from one surface to the other. You can use 300 series in combination with 400 series ( chromium only )without galling. On a different note, I believe some Wheatstones were made with the best quality reeds advertised as having purposely rounded edges. Reed steel should be hard enough already. I find the blue 1095 shim steel at the low end of acceptable, though it sounds just fine. The UHB20C alloy I use ( also used for compressor valves as well as the accordion industry) is harder and retains its set much better, and shears much more cleanly than 1095, which tends to shift sides of the shear line along the cut leaving a sort of battlement shaped surface that needs to be filed smooth. I don’t think there is much of a fatigue problem with well made reeds without stress risers. Shearing can cause micro cracking that may not be noticed or removed by edge filing, and these can be failure points that show up some time later. Stainless alloys for compressor valves probably would do just fine as is. I expect the tumbling operation is to effectively polish out the tiny edge defects left from punching out the valves, rather than to alter the basic properties. Tensile strength goes up as imperfections in the crystal structure goes down. Oh yes, the reed exercising is for stress relief and is as Chris says is best done in a room with a good door. I leave the room and let it run for a few hours/side. Dana
  25. Valves can affect tuning, but that does not sound like this is your problem. Valves can change stiffness over time, Initially stiff valves with the reed tuned under that condition, may become more flexible with use and the reed pitch will rise, sometimes by quite a bit. Likewise a flexible valve may grow stiffer with age “drying out “ and lower the pitch a bit because it won’t lift high enough to allow free air flow. Notes that are played often tend to keep the valves flexible, though aging often causes valves to curl away and need replacing. Reeds can change pitch if they change their “set” (the distance above the plane of the reed frame of the reed tip at rest ). They can also change in pitch if they are beginning to get loose, (lowers pitch) in which case, making sure the reed frame is snug in it’s dovetail ( for traditional construction ). The opposite condition would be true, except that makers tune the reeds in the snug condition. I don’t know I’d SF has been as hot and dry as the rest of the state, but that can cause loose reeds. Sometimes hybrids can have valves fall off which can raise pitch but cause slow starting of the other reed of the pair. That is until the loose valve gets stuck somewhere it shouldn’t. Dana
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