Introduction: Hyperbolic Spoon IPhone Amplifier/Stand

The speaker on my smartphone is underwhelming; as is yours. I find myself cupping my hand around the base of the phone to provides a slight volume boost in situations with ambient noise. I wondered if it was possible to accomplish a volume boost with a spoon head acting as an amplification dish. The remainder of the spoon is bent into shape to act as a stand for the phone. The overall effect is a slight gain in volume (≈ 5dB in the video below); this is not an actual amplification but a deflection (and the spoon does not actually conform to a hyperbolic shape). No additional energy is needed to provide the sound boost, therefore it can be considered as "passive". There are several similar instructables out there, from the hand-cupping technique, some snazzy paper based variants and and even some very elegant looking rigs

Step 1: Step 2: Item List

All you need for this instructable is a spoon and some tools to bend it with. I started with a large soup spoon, thinking that I would want the larger surface area and length. The results was not great, due in part to the weight of the head, making the whole rig rather unstable. The best result was obtained from a cheap dessert spoon. This was easier to deform and not as top-heavy.

"Locking sheet metal tools" provide more control. Otherwise use what you have at hand. If you live in the Matrix, then use your mind.  

Step 2: Step 3: Bend Spoon

This step covers the approach I took to bending the spoon(s). Depending on the size and quality of your cutlery, you may have to alter the length and angles to obtain the desired results. I used the "locking sheet metal tools" to do all the bending; this afforded more control on the position and angle of the bends. It is best to "underbend" rather than "overbend": the reason being that you will cause extra stress and eventually cause the spoon to break at the bend if you go back and forth. You can see a partial break on third image. 

The glass of the iPhone in contact with the steel of the spoon has very little friction. You may elect to wrap some electrical tape along contact points to ensure secure positioning. 

Step 3: Step 3: Enjoy

The uses for the "Spoon Amplifier" are limited to times when your best available screen is your phone (otherwise use your tv or computer), multiple people are watching (otherwise use your headphones), and you don't have access to external speakers (you're not home). Hunkering down to watch a movie with fellow hikers during a rain storm would meet these criteria. 

If using a bent spoon is not sufficiently eco-geek-chic to impress your entourage, you can always build yourself a "passive" hearing aid like the one shown above.


lugnutt73 made it!(author)2016-04-11

Very nice! But now you've gotten me to want to play with the same to see what I can do for my own phone... Because another project idea is JUST what the wife wants me to have... ?

Renard_Bleu made it!(author)2016-04-12

This project is pretty quick though! Try to get ot right the first time, otherwise you'll get in trouble for ruining the silverware.

lugnutt73 made it!(author)2016-04-12

It'll be good. it's all WalMart silverware. 27 spoons for $2. The ones that'll really be upset are the Honyockers when I run them out of cereal spoons.

kas227 made it!(author)2016-03-27

Love this. How about a soup spoon for a more hyperbolic shape?

Renard_Bleu made it!(author)2016-03-28

That might give it a little more kick! Newer generation phones are getting louder, but still not great. Thanks for the comment!

Iron+Cowbell made it!(author)2013-08-17

Keep in mind, though it isn't exactly stylized, it holds the smartphone horizontally and amplifies. I'd call that a win win.

Renard_Bleu made it!(author)2013-08-18


ZaneEricB made it!(author)2013-06-29

goes to show you...sometime the best ideas are the most simple. Well played!

The1PublicEnemy made it!(author)2013-01-26

good idea i usually use my hand when im holding it to get the same effect. incorporating it into a stand is a great idea!

Renard_Bleu made it!(author)2013-01-28


EricHi made it!(author)2013-01-24

Great use of an old spoon!

EnergyHandyman made it!(author)2013-01-23

Reminds me of this:

Renard_Bleu made it!(author)2013-01-23

Nice design, and more stylish than pulling out the mangled spoon in public. I hadn't realized there were so many other passive amplification design on instructables till i published and noticed five similar projects in the "Related" section on the side. There is even a guy describing the hand-cup technique (convergent evolution?). I'll add a few links tonight. There must be a good reason why they point the speaker towards where you cant see the screen...

Renard_Bleu made it!(author)2013-01-17

Thanks. Coolio appreciates his props too!

audreyobscura made it!(author)2013-01-17

Gangster's Paradise....great choice. AND awesome project.

About This Instructable




Bio: A lowly geologist who likes to build stuff.
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