Speaker in cell phone

[Jane]

I need to choose ( from different models ) a loud speaker for a cell phone. How can I find out which of all loud speakers ( I have) will be the one of the most  loud?
WIll it have the lowest resistance?Or is there a better way how to find out the best one? Thank you .

[Jane]

Or is inductance that matters?

[LateLesley]

I don't knwo if the same applies to phone speakers, but when I used to look at car speakers, there was a Sensitivity rating, which would measure the sound output @1W/1M usually measured in db.
there are a few factors that play in.
Impedance is one, the lower the impedance, the higher the watts (or probaby milliwatts in this case) you will draw from the amplifier, but it needs to match what the amplifier can supply, if you go too low, it can fry the amp.
But if you can find a db sensitivity rating, that will make a big difference. for every 3db rise, is a doubling in "loudness". But there is a trade off there too, as the sound can get less controlled, and more peaky - they usually have a less flat frequency response across the spectrum. So the sound can be harsher and less accurate.

[Renate]

Huh? You are using an amplifier, aren't you?
Are you connecting via Bluetooth or the headphone jack?

Edit: Oh, I guess you mean literally inside the cell phone.
The best way is to try.
Still, I would think only one form factor would fit anyway.

[Jane]

I mean a load speaker literally inside the cell phone.
In a cell phone there is an earphone ( it works when you have a phone call with a somebody) and a loud speaker that makes ringing ( when someone calls you).
Load speaker is  soldered in some  cell phones and it is not good to test a load speaker in a phone ( by soldering/desoldering).
First I need to find the best  load speaker that will be the most louder.
Anyone knows what is important? Resistance/inductance...something else?
(There is no descriptions on cell phone load speakers regarding parameters)

[Renate]

Well, if you want loud, get a piezo buzzer and wire it into where the the vibrator is.
You may have to dump the speaker to make room inside.

[Jane]

And how can I meassure which piezzo buzzer will be the most loudly working?

[Renate]

They are all loud. If your root problem is missing calls/notifications then a piezo would fix that.
The problem is making space and insuring that you don't leave your cell phone with the annunciator opening face-down on a pillow.

On a different plane, maybe a smart watch Bluetoothed to your cell phone.

[Jane]

Yes, thea are loud but  there are differnet models of buzzers and volume of each  can be significantly different.

[Renate]

I think that the biggest killer is the opening, the directionality and the problem of having the opening occluded.
If the phone is in your backpack/purse it's going to be difficult.
Maybe a minimal Bluetooth watch/pendant/belt hanger/pager-like might be the answer?

I don't have this problem, I leave the sound off on mine.

[wraper]

As replacement only original part or a very similar part with about the same specifications should be used. You cannot simply fit a different speaker to increase the volume because it will not fit mechanically. Also non leaking audio path must be preserved, usually done with sticky gasket between speaker and enclosure, otherwise sound volume will significantly decrease, especially at lower frequencies. Not to say if the phone became quieter over time, it could be dirt blocking audio path instead of problems with the speaker itself. Also sometimes ferromagnetic dust gets into speaker.

[Renate]

We're still missing the root problem here.
Is it:

• I want to share Tik Tok videos with my friends at a louder volume
• I can not miss a phone call as it is a matter of life and death

For #1 I would suggest a Bluetooth speaker.
For #2 there could be any number of different ways to reliably alert you to incoming calls, among them louder annunciation.
Would something glued to the back of your cell phone be acceptable?
There are plenty of 70 dBA piezo that run on 3+V.
You wouldn't even have to find space inside the case.

[Jane]

Thank you all for the replies. Yet, still no answer to my question.
How can I measure the buzzer volume( without soldering to cell phone)

[PA0PBZ]

You can't! The way that it is mounted in the cell phone has way more influence on the sound volume than the speaker itself, and you can be sure that whatever makes the most noise in that phone has already been selected by the manufacturer. Or most likely it is the other way around: the part of the phone where the speaker sits has specially been designed to get the optimal volume with that specific speaker. So that is why you are asked what you are trying to solve, and that is why you will not get an answer on your first question.

[Renate]

How can I measure the buzzer volume.

You read the data sheet.
Have you ever heard one of those annoying piezo buzzers and thought, "Hmm, that isn't loud enough."
I usually put tape over the opening.
Take apart an old smoke detector, that should be loud enough.

You know, we're trying to help here, but you're not meeting us halfway.
If you can actually state the root problem, there is a lot of expertise here (and I don't necessarily mean myself).
Give it another try please, I hate to see dissatisfied customers.

[RJSV]

If you want a safe route, why not purchase something ablutooth, already tested, and wireless.

  If you want to conduct some relatively harmless experiments, use the stereo audio output jack, Gnd. and one (wire) for each, left / right.  If you start cautious, maybe 10 ohms (better is 20) series w each speaker like a pair of boxes, each w 4 inch speaker.

How loud, really, gotta get or rent an instrument. That reading might not at first, make you happy: like 1.3 dbm, STD weighed AAS standard table....
How loud? Did he say?

[Zero999]

Thank you all for the replies. Yet, still no answer to my question.
How can I measure the buzzer volume( without soldering to cell phone)

With a sound level meter.
https://en.wikipedia.org/wiki/Sound_level_meter

[Jeroen3]

There are a few acoustic simulation packages available. If you really want to connect numbers before you make anything, simulate the acoustics of your audio path.