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  2. Yeah, well, I think I might have to retract that statement. I knew I was sticking my neck out by saying it because I never verified it myself and I hate saying things that seem like common knowledge without my own direct verification or without documentation. So I did look into this issue and found some things that may be of interest to some here. We want to compare the total energy input to the total sound energy output. Power input to the process is the result of our muscle power, and of course we can measure that by measuring our force on the bellows and multiplying it by the speed at which the bellows closes or opens. We don't have to do quite that, because that power is very closely equal to the product of the force the bellows pressure exerts on the airflow through a slot (consider only one sounding reed) times the velocity of that airflow. The bellows pressure force is equal to the bellows pressure times the area of (slot) flow. Bellows pressure is easy to know, but what is the slot flow area and the air velocity through the slot? The fact that there's a vibrating tongue obstructing air flow through the slot adds complexity, but we can simplify things considerably, first by saying the actual air flow area is about half the slot area and second by taking the average air flow velocity, which, thanks to Mr. Bernoulli, is easy to calculate. That air flow velocity in fact accurately represents the power input available to the vibration (power input without vibration). Here's our reasoning: bellows pressure forces the motion, exciting tongue vibration, which leads to acoustic power output and dissipation, or heat. In turn, of course, the acoustic power output is also dissipated. Of course, acoustic power output is generated in conjunction with tongue vibration and does not result at a time after vibration, but all these details don't prevent us from getting a good estimate of the power input. Separating the mechanical energy of tongue vibration from acoustic energy would be extremely difficult if you'd want to do that with a complete analytical understanding of the entire phenomenon. But there are easier ways than that, so stay tuned. The product of bellows pressure, slot area, and airflow velocity is very simple, and for a bellows pressure of 6 inches WC, slot dimension of 2 by 0.1875 (using only half that), I get about 1.5 milliwatts of input power. What's the total acoustic power output? A simple estimate is to consider how loud the reed sounds when you're a certain distance away, converting that to acoustic power intensity, then multiplying that by the area of a sphere of that distance. Here again, we make rough estimates. If you go to the web and find typical sound levels produced by various sound sources, you learn that conversational speech is about 60 decibels at one meter and a vacuum cleaner is about 70 dB at one meter. Let’s assume we have a particularly muscular concertina player who’s an extrovert and take 70 dB at one meter. This gives a total of 0.13 milliwatts, or about 1/10 the input power calculated above. So it looks like my statement above can be accurate, but bear in mind the simplifications we made. We are definitely in the realm of order-of-magnitude reasoning. I thus would not be surprised if in some cases, say for different pitched reeds, that statement may not be too accurate. I come away from this thinking, “Okay, that’s a rough rule of thumb, but…” Best, Tom
  3. The idea for my constant pressure tuning device came from Dana, so its a 6” duct fan, in my case speed controlled by nothing more than a domestic 240v lighting dimmer.
  4. I found this: https://www.johnkirkpatrick.co.uk/gigs.asp Fri 16 Oct 2020 to Sun 18 Oct 2020 The Church Barn, Bishop's Castle, Shropshire ANGLO CONCERTINA WORKSHOP WEEKEND Chords and Keys on the Anglo. Full details to follow soon
  5. This may help...........apparently Mrs. Saggs was written with no repeats but you can sort that out. Robin Polperro Bay & Mrs Saggs +chords.pdf
  6. When my children were small we did the Suzuki violin method with them for years....from 3 1/2 to 18 yrs of age. We were constantly changing my daughter's strings because they corroded where her fingers stopped the strings and my son's hardly ever. Robin
  7. Apparently inspired by it .....! Jim......really nice interpretation, Jim. As always, great playing ! Robin
  8. Yesterday
  9. Thank you Geoff! This information is a valuable resource and I'm so glad you decided to make it available. As one in possession of two instruments form the first page, it is fun to have an idea of where they fall in the history of this great family of concertinas. There are some very interesting notes that you have included. Any idea why the numbering started with 8071? I am not at all surprised they start at a high number, but one wonders if it was an arbitrary number, or had some meaning. It is curious that the stamped numbers were not used consistently for resold instruments until 1895. Were early J Crabb instruments with stamped numbers indicative of an instrument that was not originally build for resale? I have one from that late 1880s that is stamped, but also appears to be sold by Ball Beavon. Perhaps it was not commissioned, but resold and stamped externally by Ball Beavon later? It is also really interesting that the total number of instruments produced per year appears to have hovered so consistently right around 20/year from 1876-1907. There are a few dips, but usually followed by a jump the following year, which makes me wonder if the numbers were assigned when the instrument was completed or when it was started. I'm also curious about the 337 number in the final table. The serial numbers progress from 8321 in 1889 to 8503 in 1895, so that sounds like a total of 182 in 7 years or 26 per year. All very interesting. Thanks again for sharing! Best, Jeremy
  10. I have used this process on both old and new nickel silver ends with success. Baritone Anglo with newly plated ends pictured below. Not sure there would be equal success with chromed or silver plated ends......
  11. Wes, I have been doing some research on concertina players on the Isle of Man and have turned up some newspaper cuttings about Frank Olloms and his wife Elsie. I have attached a few that may fill some gaps in his career and his wereabouts. Frank seems to have settled on the island in 1926 purchasing a shop with flat above. His wife Elsie was the daughter of John Slater who was landlord of the nearby Rosemout Hotel. It looks like Frank continued to travel as a professional musician right up to the outbreak of WW2. They must have moved to Homefirth shortly after the war, where the solicitors notice of his death confirms his Italian origins.
  12. Why Not ask Ollie directly, look for OllieKingMusic on the web. I'm unable to connect to his site at the moment. or Olliekingbox on Facebook
  13. Playford volumes 1 - 3 are available to download as abc files or PDF files. http://www.cpartington.plus.com/Links/Playford/Playford Info.html
  14. In another thread Bill N wrote .... " Posted Friday at 12:17 AM Snip, ... Snip, ...... I'm enjoying playing this and other recently composed pieces in the tradition (Mrs. Saggs & Polpero Bay for instance) that make one stretch a bit compared to some of the more straight-forward tunes in the traditional repertoire." Mrs SAGGS I have already but the reference to POLPERRO BAY intrigued me so I searched it out and listened to it on sound cloud here : ... Polperro Bay I rather liked it, so can anyone direct me towards the sheet music?? regards Jake
  15. You're probably aware of Jeremy Barlow's The Complete Country Dance Tunes from Playford's Dancing Master (Faber), which contains... well I'll let you work it out. Exhaustive and scholarly but sometimes confusing with the different tune variants. Indispensable if these tunes are your thing.
  16. I never considered the output from the speed control. Since AC is going in, I thought it might just be a switching type speed control, like a lot of dimmers that simply vary the time the power is going to the filament. Regardless, I just looked in a catalog for in line duct fans and picked a speed controller in the right power range. Sounds like you have a monster blower, more like a vacuum cleaner to work at those pressures. All I know is that my blower motor bears no resemblance to my 2 hp you may be able to force more air through the reed though physically that becomes increasingly difficult past a certain point. At some point the reed simply stops oscillating (what I call choking). The less stiff s given reed is relative to its pitch and length, the sooner this happens. It seems possible though that the greater the reed amplitude, the less time it spends in the power zone. That is an interesting concept. I know it all gets turned into heat, but is that in the air cooled reed or in the muscles / blower that does the driving? It is funny to realize since our experience is all about the exercise we get and the resulting sound out. On the other hand, since sound pressure can sympathetically drive a reed I wonder if the natural feedback mechanisms don’t increase the reed’s physical amplitude.
  17. Contact Bill Crossland, he has a process whereby he has the end polished to a high degree, then uses a clear lacquer, similar to the clear over base in a automotive paint system
  18. Yes been there done that.Its not obvious what to do so I have sent him an E Mail
  19. As some will know, health issues have caused me to step back somewhat from concertina related issues, so, due to requests for dating information regarding Crabb instruments, I offer the attached information that may be found useful or at least interesting. I have tried to provide all the information that I believe to be relevant, based on the records that exist and that furnished by current/past owners of these instruments. To those awaiting replies to dating and other enquiries, I apologise. Geoff Crabb Dating Document.docx
  20. Geoffrey Crabb

    Test

    Crabb Dating Document.docx
  21. John Kirkpatrick. See C.net event calendar: https://www.concertina.net/forums/index.php?/calendar/event/239-anglo-workshop-weekend-in-shropshire-with-john-kirkpatrick/
  22. I'm not seeing this advert. Who is JK / John ?
  23. That sounds great Jim. I love what you do with the left hand. I've learned it on both my G/D and C/G, and it's a different approach with each. I just got a new Wally Carroll C/G at Christmas- my main squeeze before that was my Morse G/D- and I've been playing it almost exclusively since then. For sure chords and bass notes for this tune are more straightforward on the G/D, but I really like how the rhythm and melody flow on the C/G. I took the youtube video of Andy Cutting playing this in Gm, made an MP3 of it, put it on the Amazing Slow Downer, and raised the pitch 4 semitones. I've been playing along with it obsessively, really focusing on the elusive "mazurkaness" that Andy imbues it with. I've added a few ornaments and variations, but won't put in chords and bass notes until I feel rock solid with the rhythm. I'm playing for a contra dance next week, and often play a waltz or mazurka during the intermission for a handful of dancers that don't want to stop. Can't wait to try this one out.
  24. 1) In some environments (eg: Reddit) it's possible to see graphs detailing user growth or number of posts per month and metrics like that. I'm sometimes interested in stuff like this (how sad is that - I should get a life!) 2) Yeah - I was actually after the total number of subscribers to concertina.net, and I was able to get a pretty close estimate from the members list (no of subscribers per page x number of pages). Ta!
  25. It's definitely not obvious... what exactly do you mean by "usage?" For users, go to search/more options/members, hit the looking glass icon. Go to the member search tab, hit "Search members" with no filter option selected. Now you get a complete member list. On the right hand side of the top bar, you can sort the list by a criterion that suits you (eg post count). Possibly you can get there quicker, but I wouldn't know how. Is that what you are looking for?
  26. I know this question has been asked (and answered!) before, so I'm sorry for asking it again, but I can't find the answer using search. How do I get at the numbers dealing with usage, number of subscribers, etc. Thank you.
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