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Laser Harp - a more simpler thought. Help? Answered

Hey Guys  :) ... Need your advice on this idea of mine  :)

> Maybe you've seen (and i think you have) the LASER HARP project on the net, well i wanted to build something similar to that but using more simpler and i hope more cheaper components and parts.

> I plan on using ARDUINO for this project. About the Laser part of the project, i plan on using a simple laser pointer placed to point upward then aligned on top of it would be a photo-diode.

> the Laser pointer and the photo-diode will act as the "Strings" to the Harp, and there will be 8 of this for the 8 notes.

> So what do you think? oh and some advice on what speaker or speakers i can use for this, but i'm hoping to use only one speaker to produce all of the eight note.

> Hope you guys can give your thoughts about this... tnx  XD



5 years ago

Hey Guys... need you advice.

This friend of mine is really bugging me with what FEEDBACK can i include in this project.

Well i said, if I can, I'll put a sensor to know how high or how low i placed my hand to block the laser path between the photo-diode and the laser pointer, which in turn will be how high or how low the volume is.

> I might have said that on the spur of the moment then,

> Anyways guys, any ideas how will this be possible?

Ultrasonic sensors would be an easy way to achieve this.
Uses lasers aimed at photo diodes as a digital input to your arduino, to produce a logic low for when you want a note to be played.
When the arduino detects a note, poll an ultrasonic sensor for the distance from your laser emitter or photodiode, whichever's easier.

If you want to produce multiple tones on one speaker, have your arduino generate the tones on individual pins and then run them all to a summing amplifer and then to the speaker.

You need a way to multiplex (look it up) the 8 notes to the arduino. 

You need to tell the arduino what to do with the 8 notes.  How to play them. 

If you want more than just on/off which will be the same as hitting all the notes with the same intensity,  (No nuance to the note.) then you need a way to read intensity of the interruption of the laser, code it, send it to the arduino and tell the arduino what and how to do with the info.

Any speaker that the arduino can power will work.  You may want to run the output to a nice amp and speaker.

It's not an easy project that can be done in a week end but taken step by step is not too hard.  Just get one part working before adding the next part.  I would do the programming first and simulate the input from the laser board.  then figure out how to interface the laser board.  Then when you are getting the inputs you want work on the sound delivery system.

Frankly, once you get the one octave working you can add all the other notes easily.

so basically this will have 8 Inputs (from the laser lines) with 1 output (which is the speaker), correct?

., from what i read in a site "It is not possible to read or write more than one pin on the 4051 at the same time, because you can only select one pin at a time."

Does this mean i cannot play 2 or more notes at the same time?


To play more than one note at a time, you need enough computing power so that when a pin is selected the software knows to plan that note for a certain length of time.  that way you only need to select that pin for an instant then you can select another pin.

I don't work with the arduino so I don't know if this would work or not.

Thanks for the great tips.

> the laser harp, like the original musical instrument, should be able to output 2 or more notes at the same time. I am really thinking how can i do this with only one speaker, or do I just go with the simple 8 speakers each producing a note on the musical scale.?

> Tnx for the advice. If you have any more please feel free to do answer.


5 years ago

If you generate 8 separate notes with attack, duration and sustain
then you can build an eight channel mixer with priority if you like.


any further advice on how i can make one and its application in arduino?