Small hammer-like actuator ideas

Yes. But you will note that some chimes are deliberately suspended "end caps".

And, then there's the matter of where they are *struck*...

In our case, this is intended to server many purposes:

- a "door bell"/annunciator (make noise)

- a "room divider" (when you enter the house, your view into the living space will be blocked by this "wall" of tubes)

- a bit of pseudo-art (since it's the first thing you see on entry to the house, it shouldn't look too shabby! :> )

So, I'm imagining the materials won't be cheap -- figure the longest tubes need to be ~6 ft and need to be made of something that is visually appealing (polished brass, copper, etc.)

I don't want to engineer a striker & support system only to discover that it sucks in practice :-/

Reply to
Don Y
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OK, I'll take your word for it ;-) I've already made my phondness for fyziks known, here... :-/

Though you can get a pleasant tone from a struck piece of PVC. It damps quickly, though.

No idea. My bout with musical instruments ended some 40 years ago...

The problem is exactly the "machining" effort required. You can't just take out a file and tweek it a bit.

Likewise, drilling for supports becomes a challenge.

(But it would be the most visually striking approach, without a doubt!)

Likewise explaining why you can't just clone a Stradivarius :-/

The *terror* here is that you (I) find *a* chime that looks promising. Only to discover, later, that it was an "exception" and the rest of the set that you (I) fabricated sounds like crap!

I think I will have to start with visual characteristics of the materials, first. Then, purchase some and evaluate the sound quality at the low, middle and high end of the range that I plan on addressing. Rinse, lather and repeat.

*Then*, sort out how to handle "striking them" (since the material may suggest/preclude different options).

(sigh) Far more "empiricism" than I had hoped for but, perhaps, that's part of what makes it unique?

--don

Reply to
Don Y

It's not so hard. With tubes, pick a length/diameter ratio that's quite large, and the lateral modes will dominate over all others, so any dischordance from circumferental modes will be minimal. If the material you choose is of fairly consistent manufacture, the sound will be consistent too.

With gongs, guitars, etc, there are so many more modes than with a simple tube.

Reply to
Clifford Heath

Well, as some physics aficionados are fond of pointing out: everything's relative. There's no such thing as "rigid", if you really look at it.

It may take prolonged exposure to a book to learn enough of the physics of musical instruments to do this project with some more confidence than the "let's try this and see what happens --- who knows, might even work!" you're currently at. You could ask your local library to get you a copy of "Science of percussion instruments".

So no good for a chime. There's a reason gongs, bells and other chimes are invariably made from metal. It might be possible to build a poor man's cheap version of xylophone from PVC, but never a chime.

Well, looks like you've just undone that ending, and turned it into a

40-year break instead. That thing you're planning is, for all intents and purposes, a musical instrument.

You can --- you just need a rather different type of file.

Diamond bit in a dremel should usually work. You do have to be _careful_, though.

Not completely. People have figured out how to get that stuff just right hundreds of years ago to cast bells of all sorts and sizes --- from the "dinner's ready" miniature bell to massive church bells.

Exactly. Science (and a certain disdain towards budgetary constraints) can take you most of the way, but there's that last nuance that depends on luck: a piece of wood being just right, the instrument builder's mood that day, and so on.

I'd advise towards the exact opposite approach. Outer appearance is literally just surface detail, after all. It's the music that depends on the whole body of the thing. Changing the surface without affecting the tone significantly is tricky, sure --- but fixing the sound without rebuilding the whole thing from scratch will be a whole lot trickier still.

Reply to
Hans-Bernhard Bröker

I will look into it.

Sorry, I was just commenting that "you can get a pleasant tone". Sounds more like "wooden blocks".

Though your xylophone comment suggests *bar*-stock could be an alternative. Off the top of my head, though, I can't imagine many materials available in this form (steel & aluminum).

Yes, though playing an electromechanical "instrument" electronically is a much different level of commitment than a "real" instrument "manually" ;-)

I'm looking at the process from a practical standpoint. If it looks like crap, the sound quality won't be worth anything to me (at least not in this deployment location).

And, if you go hunting for sound quality first, then you have no EASY criteria to narrow your selection. You just start buying pipe, cutting, filing, tweaking/tuning and *then* evaluating with an ear towards ruling it in or out. That's a big investment for something that might not pan out: "Ah, here's a 2 inch diameter LEAD PIPE. Let me buy 8 feet of it, machine it and see what it sounds like..."

OTOH, you pick the "pretty ones" first and hope you get lucky and find something that "sounds acceptable" (remember, I'm not competing with a pipe organ in a cathedral, etc. but, rather, a $19.95 doorbell you could purchase from the hardware store!). If your first attempt fails, find something *else* "pretty" and try again.

Reply to
Don Y

But, as I want the diameter to increase, the length must increase *quicker* (?). And, since there is a maximum length that I can support (for the lowest tone), that will ultimately decide what I can and can't achieve...

(that will have the effect of driving L/D up more significantly)

Reply to
Don Y

For flat bar, brass and copper are readily available too. Things like titanium, nickel or zinc are usually sold in sheets (which you can, of course, cut into bars yourself*). All of those are commonly available as round bar stock too, which could probably be used to make a slightly unconventional xylophone, but tube would likely be better.

But I wanted to mention brass specifically - it certainly a material that's associated with musical instruments, presumable for a combination of good sound qualities, ease of working, and decent level of hardness.

FWIW, I've bought some small quantities of unusually sized stainless tube from the folks in the following link, and they have a lot of stuff, in a lot of size, with no minimum orders:

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*Ignoring the world of hurt that is machining titanium
Reply to
Robert Wessel

I guess this is the first time I noticed this requirement.

Um, have you considered placing the tone bars/tubes INSIDE some visually appealing tubes? You could use the best sounding material, perhaps more easily conceal a striking mechanism, and still get the look you're after. For instance, some thin anodized aluminum in different lengths/diameters with - say - tubular bells or tone bars or w'ever suspended INSIDE with their appropriate strikers. Of course there 'may' be some muffling of the sound, but the overall tone and volume could still be equivalent or better than choosing the 'wrong' material based on appearance and trying to force good sound from it.

Reply to
1 Lucky Texan

Well, there's *always* a "maximum length" constraint. :>

I suspect mine is probably longer than most (~6ft+).

OTOH, the fact that I want to *use* much of that length for as many bells as possible is also a constraint...

That's cheating. I could just as easily build a stained glass window in front of the chimes and let *that* serve the artistic and "room dividing" functionality.

(Or, a speaker playing a WAV file -- which is the current "doorbell")

But, opinions here have suggested that it isn't *too* difficult to find an "acceptable" tonal quality. The problem is trying to get to that solution without going through a boatload of time and money.

E.g., I looked at thick-walled brass pipe and figured I would need to mortgage the house to pay for the pipe, alone! (that's a wee bit over the top -- even for *my* sensibilities! :> ) Maybe Clifford's idea of cannibalizing some chain link fence is the *right* approach afterall! :>

Reply to
Don Y
[attributions elided]

That's an idea. It seems like bar stock is cheaper that pipe. Though I have no idea as to how to correctly scale the dimensions and admit to just a SWAG. It would probably be easier to design a striker -- since there is no way to *hide* it, you don't even have to *try*!

And, if highly polished (and lacquered), deliberately striking them slightly off center so they "twist" a bit could be visually appealing (think: play lights off their surfaces)

I was still thinking along the lines of hanging the bars.

OTOH, I recall an "annunciator" (from a telco CO) I was given as a kid that suspended a bar (aluminum?) below a tuned cavity and struck it from below electromechanically. Made a very nice, rich sound and the sound box amplified it dramatically! (I suspect one would have to make a cavity for each such bar to get this effect ?)

Yes. There's got to be a reason it's used in so many musical instruments, doorbell chimes, etc. Esp when there are cheaper materials out there.

I wonder what aluminum *castings* would sound like? These should be relatively easy to make specific sizes/shapes. And, a lead pipe cinch to tune! (?)

Reply to
Don Y

Bar won't oscillate in the same modes as a tube. It might be pleasant, but it won't be a similar sound. FWIW, glockenspiel's and xylophones use bars, they sound quite unlike tubular bells.

Reply to
Clifford Heath

No doubt!

I think a bar needs a "tuned cavity" to work against to get the same sort of richness that a pipe would inherently have.

Reply to
Don Y

Maybe, but the air cavity isn't the main point. The point is that the metal itself moves in different ways, propagating different wave fronts into standing wave patterns at different frequencies.

Don, do yourself a favor and visit these pages and follow your nose to more: , , .

Then think about what sorts of modes you might get in a bar vs a tube, and which of those modes will radiate sound.

Clifford Heath.

Reply to
Clifford Heath

Understood.

Yes, I'm sure of that. The "annunciator" I had as a child had a far purer tone to it than a "bell" (though the initial contact of the striker was very hard and "metallic"/overtones). IMO, it was a nicer sound than a "bell" but I'm sure the resonating cavity was responsible for much of that quality. Common sense suggests this cavity would increase in size with decreasing frequencies. So, it would be completely impractical to make a large "instrument" in this way :-(

(besides, the cavities would be visually unappealing and hard to disguise!)

Will do. Thx!

Reply to
Don Y

I meant the graduated DIAMETER part. sorry I wasn't clear. I just didn't realize you also wanted the diameters to increase.

I think that unnecessarily increases the difficulty. But, I admit it could make a better instrument. I just don't think I've seen any struck rod or tube based musical instruments that increase diameter - just length. Bells ('bell choir' - type bells) DO seem to increase in all dimensions for lower tones)

Reply to
1 Lucky Texan
[attributions and other stuff elided -- hopefully retaining the essence of this portion of the thread]

No, that was NOT a goal (though it might end up being a consequence of an implementation).

Rather, I was commenting that increasing the diameter of the pipe requires the length to increase -- for the same target "note". And, that the length increases *faster* than the diameter to keep that tone constant.

(Hmmm, no, I think I may have that *backwards*? E.g., a doubling in diameter requires *less* than a doubling in length!)

I.e., I want to fill a space that it ~7 ft tall and ~6 ft wide to create an effective "screen". Assume the tops of all pipes are aligned, vertically. If I start with (i.e., the *longest* pipe) a 2 ft pipe, I don't have a very effective screen (since you can see right under it!).

OTOH, if I start with a 6 ft pipe, then each pipe will get progressively shorter. Eventually, I will end up with a pipe that is too short to make an effective screen at that point!

If I make each pipe WIDER, then I can span that 6 ft width with fewer pipes. Ideally, I can span it *twice* and end up with two rows of pipes -- one in front of the other. This would allow the longest pipes to form the screen and the shorter pipes to sit in front of them (giving me the same range of "notes" while maintaining the "screen")

Large pipe organs do. But, they cover more octaves (and, it could be a simple economic issue, there).

Reply to
Don Y

ord's

Pipe organs are not 'struck' pipes - they are whistles, so, there may be good reasons all their dimensions increase - maybe for loudness issues? But I get your original point.

If you discover a fun support mechanism it might be 'columns with a tube mounted to the left and right. That would 'extend' the width AND help create a screen. you could 'fold' the smaller pipes back under the medium sized one. basically, when the pipe size gets to 3' (one half of 6') reverse direction and mount them under the long ones. (maybe that's what you meant by "in front of"?) That does appear to negate making the divider 'wider' however. Also, there's no musical reason you couldn't mix them any way you want so, w'ever it takes to get the width you need. Hmmm - I wonder if rectangular tubing would work? Might help with the screening issue if they were wider than equivalent tubes, be lighter than bar stock - but look like bar stock.

interesting.

Reply to
1 Lucky Texan

Yes. I was offering it up as an example of how instruments tend to scale to the frequency ranges they are trying to address. E.g., timpani produce markedly lower frequencies than snares.

Sorry, I don't follow. ("columns??")

Yes. Though I had thought of arranging the pipes in nonsequential order. I.e., instead of {1, 2, 3, 4, 5, 6, 7, 8} (assuming these represent sequential "notes" of increasing frequency), do something like {1, 3, 5, 7, 8, 6, 4, 2} -- assuming I didn't make a typo in there.

The former gives you a "triangle" (blech, correct to 0-th order) shaped wall while the latter gives you something like a "filled in 'W'" (assuming the outer limbs of the W are vertical). You can then arrange a second row (i.e., 9 - 16) in front of these.

Yes. The only way to get width (and length) is to start with really long tubes having the widest possible diameter. So, you end up with enough "long ones" to make an effective screen and place the balance in front of these (to get the full tonal range)

From my first passes at material prices, I think the goal will be to find something *scrap* (inexpensive); then appearance (hopefully being able to "dress up" that "scrap"; then tone quality :-/ I am hoping that others' comments regarding the latter prove to cover many materials...

Reply to
Don Y

Aluminum comes in a lot of types. For this use you probably need a high silicon content aluminum to make sure it is as hard as possible to sustain the note.

Even high pressure castings will likely need to be machine finished to create a smooth surface and sharp edges to maintain color in the sound.

w..

Reply to
Walter Banks

n the

eate

I was thinking castings are notoriously porous too and/or would need to be burnished or shot-peened or w'ever.

There are plenty of shapes of mill stock. I don't see where casting is 'required'.

Reply to
1 Lucky Texan

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