How long is too long?

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How long is too long?

Postby TerryMcGee on Wed Feb 27, 2013 5:28 am

John Gouwens, in responding to another post, made reference to long down-wires, particularly where the trebles are at the top of the frame. (I've started a new post as I don't want to derail that conversation.) But I wonder if we would find agreement on what defines ideal, medium, long, and catastrophic lengths of down-wires? Anyone care to kick off the bidding?

Would we find agreement on the symptoms? Is it only the trebles we need to be concerned with, or does the noticeable effects go further to the left than that?

(Now if you're worried about falling off the frame holding one end of the tape measure, just measure or estimate the distance between two steadies, and multiply by the number of gaps between the steadies up to the treble bell level. Then add the bits under the lowest steady and from the ceiling of the playing room down to the adjusters.)

Terry
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Re: How long is too long?

Postby JohnGouwens on Wed Feb 27, 2013 5:33 am

NOTE: There are enough responses in this thread so that the more recent ones are on a second page. Please go there to see the latest.

Inevitably, the issues of how heavy your largest bells are, and how well the structure can accommodate heavy bells way up high are factors. Also, many carillons, especially in Europe, have some bass bells below the playing cabin, with the rest being above. The transmissions is a little more complicated that way, it becomes much easier to accommodate the treble bells close to the console if the large bells are either much higher in the frame or in a lower belfry. It has certainly been done! The carillon at Indiana University has its largest bells high up in the frame.
http://www.bloomingpedia.org/wiki/Arthur_R._Metz_Memorial_Carillon
Mind you, that is a terrible installation in many other ways!

The treble bells have the lightest clappers as well as the lightest bells, and therefore are the most sensitive to any complication of the action that slows the clappers returning following a stroke. Also, it is in the treble range that you most need to be able to do good trills and tremolandi, so again, the simpler and more direct you can make the transmission to trebles, the better. Therefore, the closer you can get your top octave to the console, the better, provided they are up high enough to carry well to the ground. Smaller bells project their sound more directionally than do the large bells, so if you are in, for example, an 80-foot tower, if the top octave of bells is only four feet above the belfry floor, those bells will barely be heard on the ground. So, the trebles need to be high enough so that there are sight lines from the bells to where listeners would be. Some designers of carillons put trebles way up high on the frame for that reason. In my experience, that always compromises how well those bells ring. Since Terry is asking this, I will address this toward the Canberra carillon - 53-bell "grand" carillon, with an F# bourdon of some 13,000 pounds, keyed to G. That was a twin to the Kansas carillon originally, so I am very familiar with it. The four largest bells take a lot of headroom, and if they are at the low end of the frame, but above the console, you inevitably have too-long down wires for the trebles, even if they are the very next layer. It is major surgery to re-arrange an existing carillon, of course, but since you asked the question about what is the best ultimate solution, if a carillon that size has the four largest bells below the playing cabin, with the rest of the instrument above, with trebles starting maybe 8-12 feet above the playing cabin roof (depending on sight lines), then if you have the larger bells progressively higher in the frame, with low "C" at the highest level, that's the best you can really do. Also, that way, the large bells don't "mask" tonal egress of smaller bells.

To your question, are long wire runs less of a problem on larger bells, most definitely. The heavier clappers keep the action more taught, the larger bells are less prone to "clunking" if a clapper doesn't rebound as quickly as it should, and we simply don't do that much really rapid playing in the bass. Assuming you're not dealing with an inordinately narrow tower, there's no reason any wires to bells above the playing cabin should be longer than 20 feet, even to low C. Wires going below, to the four largest, can be longer, but that isn't really a problem in that range.

Those are my thoughts on the matter!
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Re: How long is too long?

Postby TerryMcGee on Thu Feb 28, 2013 12:11 am

Thanks John, fulsome as ever! I can see you are a proximate trebles extremist of a very high order!

Now it's not actually Canberra I had in mind (I can imagine the reaction I'd get if I suggested moving bells around as well as all the other things on my agenda!). I'm talking of adjusters to treble transmission bar lengths of around 10.5 metres, or 35 feet. So let me reverse my question: Is 35 feet "long" or "catastrophic"?

I've just done some maths (hopefully accurate - feel free to check!) to compare the weights of the clapper and the wire. The C6 clapper is pearshaped, about 55mm diameter and 85mm high. I've taken that (as a first approximation) as a sphere of the average diameter, 67.5mm, giving me a volume of 0.000161m3 and a mass of about 1.2KG, or 2.6lbs. The wire, 10.5 metres long and 2.25mm diameter gives me a volume of 0.000042m3, and a mass of 0.32Kg or 0.71lbs. So even that great length of rod appears only to reach 27.5% of the mass of the clapper. (Someone please check that maths!)

So that doesn't seem so bad on the face of it, especially when we remember we also have to add the combined mass of the down crank, down wire, umbrella, adjusters and baton.

Is it possible though that weight or its inertia is not the only or real issue? That perhaps it's the flexibility or some other factor of the long down-wire that is having increasing effect as clappers get lighter? Anyway, back to my revised question: Is 35 feet "long" or "catastrophic"? Can someone with a similar or even longer length of down-wire to the trebles comment?

Terry
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Re: How long is too long?

Postby JohnGouwens on Thu Feb 28, 2013 3:59 am

I will not pretend that I could check your math, my friend. Here's a question, though - are those clappers straight-shafted or do they have an elbow bend in them? If the latter, the clapper is moving too much laterally, and not enough vertically. It reduces the ability of the clapper to rebound - or to recover from a keystroke. 35 feet for treble bells on a Taylor - I'd call that trouble, yes. Not so hard to test, though. Take a couple of the worst bells, disconnect the down wires from them, and connect a couple of short wires to clevises on the same arm. Give each a tug. Does it sound better? I'll bet it sounds a lot better!

So, is this for Sydney or Bathurst?
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Re: How long is too long?

Postby TerryMcGee on Thu Feb 28, 2013 7:23 am

The trebles are straight, hinged from centre. The basses are bent, and hinged from crownstaples increasingly offset from centre towards the strike point as you go lower in pitch. So, yes, Bigelow's "scrape angle" issue is well-represented. As well as the pendulum effect you refer to.

Those figures were for Bathurst. It doesn't have any down wires at the moment, so not much scope for comparison! The original down-wires lie bent and tangled in two heaps in two separate rooms. It's not a pretty sight.

Now there is room at the bottom of the bell chamber to build a new playing cabin, but that would only reduce the down-wire length by 3.8 metres, 12.5 feet or about one third. But that might also introduce enough additional problems and expense to make the project non-viable at this time. I'm not sure the gains from reducing the wire length by that proportion are enough to risk the project. There are many other things on the wishlist - increase in range of bells, reduction in transposition, full weight straight clappers, etc etc. I'm inclined to think it would be better to get the installation actually working and then appraise where to go from there. The people of Bathurst have been waiting 75 years for this, and 2015 is their 200th birthday. Time is short and the list of jobs is long!

Terry
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Re: How long is too long?

Postby JohnGouwens on Thu Feb 28, 2013 12:19 pm

Bathurst sounds like a prime candidate for carbon fibre rods.
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Re: How long is too long?

Postby FrancesNewell on Thu Feb 28, 2013 3:54 pm

Terry
What do you mean by reduction in transposition?
Can you do that?
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Re: How long is too long?

Postby JohnGouwens on Thu Feb 28, 2013 4:36 pm

I think what he means is adding larger bells to bring the set closer to concert pitch. The Bathurst bells have never been connected to a manual carillon console, only played automatically or at least by electric or electro-pneumatic means. Now they are looking at making it into a proper carillon.
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Re: How long is too long?

Postby FrancesNewell on Thu Feb 28, 2013 8:59 pm

How can adding new bells change the pitch of the bells that they already have?
These are actual bells, right? Not computer-generated sounds?
do the big overtones of larger bells make the other bells' resonances sound like they are on a higher or lower pitch?
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Re: How long is too long?

Postby TerryMcGee on Thu Feb 28, 2013 9:27 pm

Sorry, Frances, I was trying to be economical in words, and went too far! You are exactly right, a bell is a bell and can't be retuned. But it can be relocated on the clavier, and other bells snuck in to replace it. Rather than talk about it here, I'll open a new topic, as I think it would be very interesting to hear views.

John, I'll check out carbon fibre prices. I live in fear....

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