Anyone ever put a pick-up onto a handsaw?

[rjb]

After all these Gyrations, He may have jumped off a Bridge By Now!

Don't worry, we're honing in on a solution....
Hey, where is tubeswell?

I was just thinking, the conventional instrument closest to a saw is a fiddle. Instead of asking a bunch of guitar-centric electronic geeks, he might do better asking fiddlers- or sound guys who work with fiddlers.

[rjb]

My grandad was a saw player... maybe a good close mic like this some how affixed to the handle could work.
DPA Microphones :: Close-miking a cello with condenser microphones

I don't know how I missed this post.
All silliness aside- I think the simplest and "best" (most natural) sounding solution will be a well-placed clip-on condenser microphone.

[Mike Sulzer]

Yikes... all that just to play the intro to Good Vibrations?
Some fiddlers like carbon fiber bows... any chance you could make the blade carbon fiber?

Hoowee,
-rb

If that is all you want to do, just use the microphone. If you do not like playing with ideas, you do not have to read or respond.

[Mike Sulzer]

I like this because it keeps the the thing out on the stick as simple as possible. I think the 1" neo is way too string; it will be difficult to handle. Also, the large size might smear out some harmonics.

I do not have access to a musical saw so my answer below is simply a mental exercise to explore with a quick experiment to test the possibilities. Here is how to do it.

Use the concept of a "moving coil pickup" (search this forum for this phrase) where the vibrating string in a magnetic field produces an output except that the saw blade is now the moving string. Mount a magnet on a stick or bracket hanging over a location near where the blade is being bowed. Attach a wire between the handle (between the lags) and the saw-tip-handle with that wire looped through a 1000 turn toroid current transformer (CT). Try it with 1 turn and then 2 turns. Attach the blade to the ground wire of a 2-conductor mic cable. Attach the CT output to the two microphone center conductors. Experiment with strong neo magnets and weaker ceramic magnets. Maintaining the distance between the magnet and the saw blade surface requires some experimentation. Stewart Mcdonald has a nice 1" strong round neo magnet with a center mounting hole. Radio Shack sells a 5-pack of ceramic magnets 1" X .75" X .125" thick with a .187" mounting hole in the center. You can experiment with the location of the magnets and the amount of magnets that capture the right harmonics to make the amplified saw signal sound pleasant.

If you try this, let us know if it works?

Joseph Rogowski

[rjb]

...Use the concept of a "moving coil pickup"....

I think I feel a "single loop pickup" coming on.

Mount a magnet on a stick or bracket hanging over a location near where the blade is being bowed.

Since the blade is in constant motion, I'm not sure how you would do this.
But the magnet may be light enough to be mounted to the blade, with a spacer.

Attach a wire between the handle (between the lags) and the saw-tip-handle with that wire looped through a 1000 turn toroid current transformer (CT).

I'm not sure I'm visualizing this correctly- but sounds like a whole lotta wire flexing.
While the blade, bent into an "S" shape, constantly changes position, won't the area enclosed by the blade and the wire constantly change? Does this matter?

[rjb]

After all these Gyrations, He may have jumped off a Bridge By Now!

Lately, I'm feeling like my initial "hula hoop" suggestion was relatively sane.

[Mike Sulzer]

I'm not sure I'm visualizing this correctly- but sounds like a whole lotta wire flexing.
While the blade, bent into an "S" shape, constantly changes position, won't the area enclosed by the blade and the wire constantly change? Does this matter?

Might be able to arrange things so that there is a potential developed between the top and bottom of the blade so that both connections can be taken at the handle.

[tubeswell]

I'm right here watching the discussion unfold. I never expected this response. Outstanding! And some really good suggestions! Each one has me thinking how it could be done. (And I'm still thinkin' at this point).

[rjb]

Might be able to arrange things so that there is a potential developed between the top and bottom of the blade so that both connections can be taken at the handle.

I'm almost afraid to ask, but which surfaces are you defining as "top" and "bottom"?
A potential developed across the steel blade?
Now I'm really not getting it.

[Mike Sulzer]

I'm almost afraid to ask, but which surfaces are you defining as "top" and "bottom"?
A potential developed across the steel blade?
Now I'm really not getting it.

Edges, not surfaces. Hold the saw as you would for cutting. The plane containing the blade is vertical. Put a magnet with the pole facing horizontal near the blade. The field lines come out of the pole and through the surface of the blade. The field lines diverge as you get further away from the magnet, so if the blade moves towards and away from the blade, the flux through the blade changes. (A vibrating blade should have part of its motion towards and away from the magnet.) The law of magnetic induction tells us that a closed path containing time varying flux with a component perpendicular to the path has an voltage around it. (Think about the varying flux through a coil inducing a voltage around the coil.) Such a path can include a wire going to and returning from a transformer. We do not need a magnetic blade for this; we just need a conducting path, but I think it would work sort of OK with the steel blade, better if you fasten a copper conducting path to it. You could do still better by further modifying the blade, but I realize that you already consider this too complicated.

[rjb]

... I think it would work sort of OK with the steel blade, better if you fasten a copper conducting path to it. You could do still better by further modifying the blade,

If I get your gist, now you want to grind the teeth off the blade, and run copper tape around its perimeter?

but I realize that you already consider this too complicated.

Not "too" complicated, just unnecessarily complicated. What do these contortions buy you?
Why make irreversible modifications to a musical instrument, just to amplify it- if simpler, effective, non-invasive solutions exist?
Would you install a Charlie Christian pickup in a Stradivarius? Same principle.

[rjb]

Figuring that if we sat around theorizing about this any longer, we'd all get hemorrhoids, I got off the pot and tried a 5-minute experiment.

Duct-taped a guitar pickup to the handle of a saw, positioned over the blade; played through a Fender Frontman Reverb practice amp. It kinda works.

I am not a saw player, and do not own a flexible-blade musical saw.

Used a Disston cross-cut saw with 26" blade. Held handle between knees, held tip with adjustable pliers; bent blade into an S shape (not so easy with a "real" saw) and tapped blade with a paint brush handle.

The pickup is an old DiMarzio single coil, with an attached spring for mounting in the sound hole of flat top acoustic guitars. Just happened to have it lying around.

Had no problem with feedback, but maybe because (mounted in this position) the pickup wasn't all that sensitive. This particular pickup is somewhat microphonic, and seemed to emphasis the drumstick "hit" over "sproing". I was able to increase sensitivity somewhat by sticking small neos to the blade; didn't damp the sound noticeably to my ear- but you have to remember that I really don't know how to play this thing. I didn't try installing an arm on the handle- but when holding the "instrument" in playing position, it is evident that the max length from the handle is about 3" before the blade starts moving significantly from "home" position.

Recommendations:
- I still think a well-positioned clip-on condenser mic will be the easiest and best-sounding solution.
- Piezos are microphonic by nature, and prone to handling noise and feedback. (But don't let me stop you from trying it.)
- If you try a guitar pickup, prolly the hotter (and less microphonic) the better. With saw in hand, you'll see that you can't mount the pickup more than about 3" from the handle before the blade starts wanting to hit the pickup.
- If you try any of the DIY pickup suggestions, please report back. Obviously, none of us has actually tried this in real life.
- Have fun.

[tubeswell]

TFT for going all out and experimenting rjb. So the p'up was attached to the blade handle and 'cantilevered' out over the blade?

[rjb]

So the p'up was attached to the blade handle and 'cantilevered' out over the blade?

Sort of. I just duct taped the pickup's mounting spring to the handle. Not an ideal situation.

If I had one handy, I would've tried something more like this. Guitar Parts Resource sells them for $19.99 U.S.
Guitar Parts Resource: Pickups Other

[salvarsan]

I have refrained from responding to what I think is a *fascinating* idea for fear of stomping on good ideas.

1) Widen the handle groove to accommodate both saw and strip piezo sensor.

2) Mount a guitar pickup at midpoint on the saw

Is playing a saw blade sexy?

Ya damn skippy, it is!