Brymen BM829s beep volume

[Toolio]

Hi, i am new to this forum but i have a question that i couldn't find answered anywhere on the internet.
Perhaps i am the only one that has this question. There seems to be no better place than to ask it here so here it goes:

Is there a way to change the beep volume on my Brymen 829s multimeter?

I just bought it and it seems to be a very good multimeter but one thing that annoys me from the start is this very loud beep that you get to hear a lot with this meter. There is a way to temporarily turn it off but i don't mind the beep, just i wish it wasn't so loud.

I couldn't find a service manual anywhere but my hope is that there must be a potmeter in there somewhere that can lower the beep volume.

I hope i can turn this great multimeter into an awesome multimeter.

[Fungus]

You can open it up and insert a small sock into the speaker. 

[Kean]

Assuming that model has a typical round beeper (like BM235), you can just place some tape over the hole

[Toolio]

Hey that sounds like a good solution
Where would this speaker be located and how can i recognize it?

Here is a photo of the inside but i don't recognize a speaker.
Do i need to remove that print? Or is it on there?

[Kean]

Appears to be on the other side of the PCB between terminals BZ+ and BZ- (just to the left of the main IC)

[Toolio]

Appears to be on the other side of the PCB between terminals BZ+ and BZ- (just to the left of the main IC)

Correct, on the back of the pcb are 2 springs under BZ+ and BZ-

[Toolio]

The actual speaker is on the back of the case, only connected by the two springs. it is rather large, which explains the loud beep:

[Toolio]

I pealed away the foil a bit so the speaker becomes totally visible. The speaker is glued tight to the case so i don't think i have a chance of removing it and putting some tape behind it. The most effect would probably be to put tape on the front but then the springs won't make contact anymore. Not sure how i am going to muffle this. Any tips?

[Toolio]

Put some tape on it and spared the holes for the springs but now it's not beeping at all anymore.

[Miti]

Forget about the tape, that works with a standard 12mm or so buzzer. You can't cover the contacts to the piezo buzzer, you won't get any sound out of it. In your case the only solution I see is a very invasive one, if you are really committed to reduce the volume. Cut one of the traces that goes to the springs and add an SMD resistor series.
You could start with 1K and go up until you're happy.

[Kean]

Yeah, sorry!  The tape idea will only work with an enclosed piezo that has a hole that can be blocked.

The BM835 uses an enclosed piezo, so I thought the larger 800 series models would too.  In fact I thought I had seen a photo of one, but must have mixed the models up as I just opened up my BM869s to confirm it looks much like your BM829s.

[Kean]

In your case the only solution I see is a very invasive one, if you are really committed to reduce the volume. Cut one of the traces that goes to the springs and add an SMD resistor series.
You could start with 1K and go up until you're happy.

For a less invasive solution, maybe inserting a semi-conductive material between one of the springs and the piezo contact?
Something like a small piece of black conductive foam, or some other carbon impregnated material.

[Fungus]

Put some tape on it and spared the holes for the springs but now it's not beeping at all anymore.

If you get zero sound then maybe it's not making contact.

[Cnoob]

I used my BM867s the other day and the buzzer made me jump because it's so loud.
But It's handy to have a meter with loud buzzer for noisy environments.

My Keysight U1242C you can adjust the frequency, melody or beep, horn on or off but not volume,  with it's way too many config options to remember.
 

[Toolio]

Put some tape on it and spared the holes for the springs but now it's not beeping at all anymore.

If you get zero sound then maybe it's not making contact.

No the tape is fine. I put the rotary swith back in the wrong way
It's good now.
The tape dampens a little but not as much as i wished.
I think i will go for the resistor approach. I will need a friend to do it for me since that kind of modification is a bit out of my league.

For a less invasive solution, maybe inserting a semi-conductive material between one of the springs and the piezo contact?
Something like a small piece of black conductive foam, or some other carbon impregnated material.

That sounds like somthing worth trying before i start messing with the circuitry, thanks

I used my BM867s the other day and the buzzer made me jump because it's so loud.
But It's handy to have a meter with loud buzzer for noisy environments.

I do most my testing and mods in the night and with this device i'm afraid to to wake up the neighbours.
Doing a continuity test actually hurts my ears!

I found out i'm not the only one with this issue:

https://youtu.be/5D8jxj9chBo

Note that this Brymen has a different type of speaker that is not nearly as loud as the type in my BM829s.
And that type of speaker you CAN actually dampen with some tape.
But he simply replaced a part. Is that possible with the BM829 aswell?
Looks like it might be R30

[WackyGerman]

Well , I was so happy that my Greenlee DM 830 ( similar to the BM829S ) has such a loud beeper    . In loud enviroments it is really helpful . For a lab it is too loud . It is more suitable for rugged field use than a lab . But it is a really good solid multimeter , built like a brick .  . A little more helpful would be an option to change the frequency . The buzzer of the alarm systems on ships have the same frequency like the multimeter so when an alarm occurs you cannot hear the multimeter