Speaker in cell phone - Page 1
Forum section: electronics / beginners

author: Jane
author_rank: Frequent Contributor
timestamp: August 12, 2020, 07:33:45 pm
content: 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 .

author: Jane
author_rank: Frequent Contributor
timestamp: August 13, 2020, 06:48:25 am
content: Or is inductance that matters?

author: LateLesley
author_rank: Frequent Contributor
timestamp: August 13, 2020, 01:38:39 pm
content: 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.

author: Renate
author_rank: Super Contributor
timestamp: August 13, 2020, 02:10:26 pm
content: Huh? You are using an amplifier, aren't you?Are you connecting via Bluetooth or the headphone jack?Edit: Oh, I guess you mean literallyinsidethe cell phone.The best way is to try.Still, I would think only one form factor would fit anyway.

author: Jane
author_rank: Frequent Contributor
timestamp: August 13, 2020, 04:22:48 pm
content: 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)

author: Renate
author_rank: Super Contributor
timestamp: August 13, 2020, 05:44:26 pm
content: 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.

author: Jane
author_rank: Frequent Contributor
timestamp: August 13, 2020, 06:23:03 pm
content: And how can I meassure which piezzo buzzer will be the most loudly working?

author: Renate
author_rank: Super Contributor
timestamp: August 13, 2020, 06:56:14 pm
content: 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.

author: Jane
author_rank: Frequent Contributor
timestamp: August 13, 2020, 07:41:11 pm
content: Yes, thea are loud but there are differnet models of buzzers and volume of each can be significantly different.

author: Renate
author_rank: Super Contributor
timestamp: August 13, 2020, 07:59:20 pm
content: 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.

author: wraper
author_rank: Unknown
timestamp: August 13, 2020, 08:11:35 pm
content: 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.

author: Renate
author_rank: Super Contributor
timestamp: August 13, 2020, 10:22:13 pm
content: We're still missing the root problem here.Is it:I want to share Tik Tok videos with my friends at a louder volumeI can not miss a phone call as it is a matter of life and deathFor #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.

author: Jane
author_rank: Frequent Contributor
timestamp: August 14, 2020, 06:58:31 am
content: Thank you all for the replies. Yet,still no answerto my question.How can I measure the buzzer volume( without soldering to cell phone)

author: PA0PBZ
author_rank: Super Contributor
timestamp: August 14, 2020, 07:13:17 am
content: 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.

author: Renate
author_rank: Super Contributor
timestamp: August 14, 2020, 10:45:58 pm
content: Quote from: Jane on August 14, 2020, 06:58:31 amYou 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.

author: RJSV
author_rank: Super Contributor
timestamp: August 18, 2020, 02:32:24 am
content: 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?

author: Zero999
author_rank: Super Contributor
timestamp: August 18, 2020, 08:37:41 am
content: Quote from: Jane on August 14, 2020, 06:58:31 amWith a sound level meter.https://en.wikipedia.org/wiki/Sound_level_meter

author: Jeroen3
author_rank: Super Contributor
timestamp: August 18, 2020, 02:03:26 pm
content: 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.