Earphone speaker frequency

Thread Starter

mustafa Alyagoub

Joined Oct 13, 2019
2
Hello everyone..
I have several questions about earphone speakers.. as I think this is related to electronics..

Is it possible to lower the frequency of the earphone speaker system?
if yes is it easy, and what is the name of the kit product for the speaker system that is used in earphones..

I am trying to find audio speakers with restricted decibels
Thanks..
 

ronsimpson

Joined Oct 7, 2019
114
Is it possible to lower the frequency of the earphone speaker system?
I am trying to understand "lower the frequency". In music that would be to play one octave lower. "Base" or "Soprano"
or
Do you want to hear lower down in frequency.
This picture is the frequency response of a small speaker. It does not make the low notes very loud. A larger speaker probably will have more Base sound. Is this what you are thinking?

restricted decibels
Decibels is a unit used to measure the intensity of a sound or the power level of an electrical signal. (loudness)
To restrict decibels is to hold back the loudness.

Please tell me what and why. I want to help but I don't know how yet.
 

Alec_t

Joined Sep 17, 2013
10,361
I'm struggling to understand 'lower the frequency' and 'restricted decibels'.
A competent pre-amplifier, or equaliser, will have controls to boost or cut bass frequencies, boost or cut treble frequencies and control loudness. Would that meet your needs?
 

Thread Starter

mustafa Alyagoub

Joined Oct 13, 2019
2
I didn't expect that fast.
Thanks for replying

To clarify, I am trying to design an earbud that is suited to sleeping.
Therefore, I have to keep in mind about the sound restriction to be safe.

Sound quality is not necessarily, but getting restricted volume maybe is something satisfying in my case.
 

KeithWalker

Joined Jul 10, 2017
413
I didn't expect that fast.
Thanks for replying

To clarify, I am trying to design an earbud that is suited to sleeping.
Therefore, I have to keep in mind about the sound restriction to be safe.

Sound quality is not necessarily, but getting restricted volume maybe is something satisfying in my case.
There are a number of circuits on-line for automatic volume control. This is one of the simplest and most effective:
https://www.electroschematics.com/automatic-volume-control/
Regards,
Keith
 

Audioguru

Joined Dec 20, 2007
11,251
Why are you designing an earbuds sleeping system when very few people wear earbuds when sleeping?
1) Do you sleep using earbuds to play pink noise (hiss) to mask backgound noises?
2) Do you sleep with music playing? Then use a clock radio like everyone else.

Why do you talk about frequencies? Earbuds are designed to play audio which has frequencies from 20Hz to 20kHz. Very cheap earbuds cannot play the very low or very high frequencies.

Why do you need to limit the decibels? Common sense and a volume control do it.
 

Tonyr1084

Joined Sep 24, 2015
3,578
Frequency: A birds chirp is a high frequency. A dog's bark is a low frequency. Unless you have one of those dogs that bounce when it barks. Nevertheless, frequency has everything to do with pitch of the sound. A child's voice is a higher frequency than an adults voice.

Amplitude: (AKA Volume) If a dog is barking in your ear the amplitude is quite high. But if the dog is across the street or down the block the amplitude is much less.

From what it appears you're describing you want a volume limiting device. Sort of an Automatic Gain Control (AGC). I'm sure that's not a difficult matter. What AGC does is boost the volume when the amplitude is low and limit the volume when the amplitude goes much higher. I think you're asking about how to use earphones at night without disturbing sleep.

Exactly why you're attempting to listen to an audio source while you sleep is beyond me. Unless you're wanting to experiment with sleep-learning. A theory that has not been proven to work. But at the same time it has not been proven to NOT work either.

Let us know how it works out for you.
 

DickCappels

Joined Aug 21, 2008
5,880
The attached patent covers a combination bass-boost and sound pressure level limiting circuit for headphones. This a completely passive circuit.

Let me know by private message if you want help contacting Walter Chu, the inventor or want to buy some of the custom-made very low power thermistors required.
 

Attachments

Alec_t

Joined Sep 17, 2013
10,361
From Fig 2 of that US patent it looks as though the PTC thermistor would have to reach ~130C (266F) before a resistance change large enough to be audible (i.e. comparable to a doubling of the headphone impedance) would occur. Can thermistors really get that hot with only a few mW of audio power and within a few millisecs?
 
Top