Is 4kHz too high a beeper frequency?

On the basis that by the time I'd hit 45, i'd lost everything over 11kHz I'd say yes, for many it could be a problem. I wouldn't chance anything over 2kHz IIWY.

Almost everyone should be able to hear it but for some it will be so high pitched or faint that they may not recognize it as something important.

Can you buzz it on and off at 300-400Hz?

piglet

I'm afraid it would be. Being able to hear a certain frequency is not the same as catching it easily when you're not waiting for it. I haven't had my hearing tested but, although it's still good enough for me to enjoy music, I sometimes fail to hear the small beeper in my DMM. It seems to buzz at around 4 kHz too.

Yes, will that help enough? We'll be driving it with a microcontroller, so we can wobble frequency, or do almost anything. Hmm, will I be able to hear it? OK, asked my phone to make 4kHz, high but I hear it fine. Maybe I'd better place several choices on the prototype PCB, which won't be laid out for minimum overall size.

My hearing rolls off prety quick right at 4kHz. I had a friend working on my computer and the beeper was beeping, and ask him why and he said he could hear it. It is much lower than 4kHz. He had the memory in the wrong slots, that what caused the beeper to sound. Mikek

Healthcare can be a noisy environment, in terms of speech, hiss, and many other beeping devices.

What other noises are there in the environment?

If people can hear the noise, then will they be able to determine the direction it is coming from and then locate /which/ specific device making the noise?

This cries out for a quick-and-dirty experiment in a representative setting. Unfortunately such settings are likely to be no-go zones for the foreseeable future.

Annoying if audible. It's really hard to localize those nasty piezo buzzers.

My vote is for a lower frequency beeper, if possible. I'm not sure I can even hear 4kHz anymore.

Use a lower frequency like A440 and ring-modulate it with some percentage of a couple octave up like 0.2. see how that sounds.

Keep an analog synthesizer handy in the lab for experiments like this...

One of the many problems I have with electronics is beeping. 4 kHz is audible to me, but not as loud as other sounds and I find the position of my head can make it disappear.

I find it extremely annoying. I tend to want to break things that make that sound. I especially hate things that beep as press buttons. The beeper gets extracted one way or the other.

The worst are things that are missing and make an intermittent, high pitched beep. When I find those things I destroy them and then try to find where they came from and make sure no more ever make it out.

I know where you live.

Have you considered having a LED in parallel with the beeper?

Dan

Yes, there's a controller-operated LED, the buzzer is to supplement that. The process takes several minutes; users probably don't look at dark LEDs. Hmm, it could start a ramp-up blinking process.

Some have nulls in their hearing spectrum and some, their HF response just rolls off like Mikek's. If it is not a piezo beeper, you could have two tones at once or alternating to make sure it is nticeable.

I think that around 3kHz is the most sensitive pitch for most people.

Also, lower frequencies, say, below 500 Hz are going to take a larger transducer and higher power.

a square at say 500 Hz and square at 2000 Hz (four octaves up) ring-modulated to give it some sums and differences and a "metallic" edge to cover the frequency bases more thoroughly

Can you store a short PCM sample in the uP?

This audio library "Turbo Risers" has all sorts of buzzes, bloops, swooshes and beeps (y'know, for the music the kids listen to these days there's an audio demo) with some parts that could definitely be cut down to a short loop and make a nice attention-getting tone.

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I would not expect that from *workers* in health care.

.... Phil

The piezo is 4 kHz because of a resonance. Connect a sounding surface to it and let the mass lower the resonant frequency to something not so annoying.

No, just a lower resonance which can be done via acoustic coupling or mechanical coupling. A little bit of thought to the packaging can probably half that frequency and produce more volume from less energy.

You mean they don't allow the deaf to work in healthcare? I never knew that.

I guess the deaf can't work in a lot of jobs where you have to interact with people. No, I ran into my deaf sign language teacher working in a store once. So that's not it.

I guess they have a test for healthcare workers. If you can't hear the beeps and boops you can't work there.

Yeah, that's got to be it.

I was going to call you an idiot, but then I realized you probably consider that to be your name at this point!