melodious sound generator

Mostly they're acoustically resonant at a certain frequency (eg.

2048Hz or 3.9kHz) using a Helmholtz cavity. You can drive them with whatever waveform you like and they'll pretty much produce sine waves.

Best regards, Spehro Pefhany

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I read in sci.electronics.design that vic wrote (in ) about 'melodious sound generator', on Wed, 31 Aug 2005:

I can't suggest an IC, but to help people like me who are deaf (14% of the population), don't follow the trend to pitch the sound in the 2 to

4+ kHz range. 400 to 1000 Hz is far more audible.

A simple phase-shift oscillator built around one transistor, with amplitude control by a measure of one-sided limiting, thus generating even harmonics, may be melodious enough for your purpose.

--
Regards, John Woodgate, OOO - Own Opinions Only.
If everything has been designed, a god designed evolution by natural selection.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

Hi,

I'm looking for an IC or a circuit which would generate a melodious sound. The application is for an indicator beep, currently i'm using a simple rectangle signal but it doesn't sound too well.

I've already tried the SAE800 circuit, but it sound too much like a doorbell and the sound sequence is not configurable.

Thanks for any help, vic

On Wed, 31 Aug 2005 11:22:17 +0100, John Woodgate wroth:

What colors do you recommend for blind people?

Jim

Use a sine signal, it will sound better.

That's interesting. I find the little ultra-short pings of (3-4kHz?) noise from my execrable Siemens phone handsets (as the rechargeable battery is dying) almost impossible to locate. The echoes probably don't help.

Best regards, Spehro Pefhany

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"it\'s the network..."                          "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

Size, drive requirements and cost of sounders, I expect. Most piezo ones seem to resonate at 4kHz.

Paul Burke

The 800-lb gorilla solution is to use the type of cellphone chip that is capable of playing programmable ringtones.

Best regards, Spehro Pefhany

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"it\'s the network..."                          "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

Oh, I expect that's WHY, but it's not deaf-friendly. And why do they resonate at 4 kHz anyway?

--
Regards, John Woodgate, OOO - Own Opinions Only.
If everything has been designed, a god designed evolution by natural selection.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

avacado and harvest gold perhaps?

I read in sci.electronics.design that snipped-for-privacy@nowhere.net wrote (in ) about 'melodious sound generator', on Wed, 31 Aug 2005:

Not a joking matter. In the same way as I use the common term 'deaf' without implying 'profoundly deaf', so I can logically explain about beeper frequencies, it's quite reasonable to discuss the best colours for people with impaired vision, short of total blindness.

Go, for example, to:

789.hcsp

--
Regards, John Woodgate, OOO - Own Opinions Only.
If everything has been designed, a god designed evolution by natural selection.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

I don't think most warning alerts are that high. Most are not high enough, and most should be driven with a square wave to make them much most directional. I can never hear what direction that truck is moving backwards. So if a 1 kHz square wave is used, you will be able to hear it, and others will be able to locate it.

greg

I read in sci.electronics.design that GregS wrote (in ) about 'melodious sound generator', on Wed, 31 Aug 2005:

The waveform doesn't make the sound directional. Harmonics in the signal can make the source easier to locate, which I expect is what you meant.

Research on making emergency vehicle sounds more locatable has shown that adding a burst of pink noise helps most, even better than a square wave.

--
Regards, John Woodgate, OOO - Own Opinions Only.
If everything has been designed, a god designed evolution by natural selection.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

I read in sci.electronics.design that Spehro Pefhany wrote (in ) about 'melodious sound generator', on Wed, 31 Aug 2005:

This evolved between mothers and babies. Young women by and large have good hearing, and it is most sensitive between 3 and 4 kHz, but that is not the fundamental frequency, unless it's a baby bird!

However, old fogeys aren't often required to care for babies, and their hearing is not good above 1 or 2 kHz. In my case, admittedly more severe than average, my hearing is down nearly 40 dB at 3 kHz and above.

--
Regards, John Woodgate, OOO - Own Opinions Only.
If everything has been designed, a god designed evolution by natural selection.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

At those kinds of frequencies, binaural hearing is useless for direction-finding, because a wavelength is just about the size of your head and your ear processing stuff can't resolve the phase right.

Cheers! Rich

Someone asked a similar question a while back. I forget the thread now.

Anyway, someone posted to a link to Rohm IIRC. There are 'melody chips' available to make cute sounds.

Graham

This is where the burst of noise helps. The ear's better at direction finding from that.

Graham

May God ( whoever he ? is ) preserve us from such things !

Have you USAans had the dubious pleasure of experiencing the 'crazy frog' tune ?

Here's a site that has a copy of what started it off btw.

Graham

I read in sci.electronics.design that Spehro Pefhany wrote (in ) about 'melodious sound generator', on Wed, 31 Aug 2005:

The echoes are the main cause of the confusion. In an anechoic room, it's much easier to locate the sound.

--
Regards, John Woodgate, OOO - Own Opinions Only.
If everything has been designed, a god designed evolution by natural selection.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk