Hello there,

I ran across this article by accident:
https://www.allaboutcircuits.com/news/teardown-tuesday-worktunes-hearing-protection-headphones/

https://www.allaboutcircuits.com/news/teardown-tuesday-worktunes-hearing-protection-headphones/

It's a very nice article, but i could use a little more information about the two built in speakers.

I dont see any value for these two speakers, like 8 ohms, 16 ohms, 32 ohms, 64 ohms, etc. I know the data sheet for the audio amp chip being used specs it with a 64 ohm speaker, but that does not mean the 3M company actually used that kind of speaker. Sure it's possible, but a direct measurement of both speakers would help a lot more.

I would like to know this because i plan a modification to the headphones such that i can switch OUT all the electronics EXCEPT for the speakers, which would then be powered by an external amplifier into the 3.5mm jack on the side of the headphones. I dont like taking them apart beforehand because i may not do the mod if they speakers are not the kind i want to use.

The author is quoted as "Nick Davis".

One of the problems with the headphones is that they might use the batteries even when not using the radio, but i'll verify that at some point down the road. Even without that possible problem though, i would want to do the mod.
The problem does show itself though when the batteries go dead, even the external input from an external amp can not be heard through the speakers any longer. After replacing the batteries, it can then be heard again. This probably means it is using battery power even when powered from an external amp, unlike a regular set of headphones. So the mod would convert them into normal headphones, but with the ability to go back to the original radio headphones.

Thanks a bunch.

Also, what holds the ear padding in place, is it glue or some clamping action?

 

Hello there,

I ran across this article by accident:
https://www.allaboutcircuits.com/news/teardown-tuesday-worktunes-hearing-protection-headphones/

It's a very nice article, but i could use a little more information about the two built in speakers.

I dont see any value for these two speakers, like 8 ohms, 16 ohms, 32 ohms, 64 ohms, etc. I know the data sheet for the audio amp chip being used specs it with a 64 ohm speaker, but that does not mean the 3M company actually used that kind of speaker. Sure it's possible, but a direct measurement of both speakers would help a lot more.

I would like to know this because i plan a modification to the headphones such that i can switch OUT all the electronics EXCEPT for the speakers, which would then be powered by an external amplifier into the 3.5mm jack on the side of the headphones. I dont like taking them apart beforehand because i may not do the mod if they speakers are not the kind i want to use.

The author is quoted as "Nick Davis".

One of the problems with the headphones is that they might use the batteries even when not using the radio, but i'll verify that at some point down the road. Even without that possible problem though, i would want to do the mod.
The problem does show itself though when the batteries go dead, even the external input from an external amp can not be heard through the speakers any longer. After replacing the batteries, it can then be heard again. This probably means it is using battery power even when powered from an external amp, unlike a regular set of headphones. So the mod would convert them into normal headphones, but with the ability to go back to the original radio headphones.

Thanks a bunch.

Also, what holds the ear padding in place, is it glue or some clamping action?

Link is broken.

 

Link is broken.

Hello,

Yes it's broken because the article does not seem to be there anymore.

Why would a whole article disappear?

 

Hello,

Yes it's broken because the article does not seem to be there anymore.

Why would a whole article disappear?

Maybe you need help from higher powers ( @jrap )

 

Hello,

Yes it's broken because the article does not seem to be there anymore.

Why would a whole article disappear?

Maybe the member was like jpanhalt and he deleted all of his "intellectual content" when he left?

 

Hello,

The link works for me.
It looks like the speaker is a 0.2 W 100 Ohms one:



That the link does not work for you, might be a permission problem.
@jrap , are the permissions for the articles correct?

Bertus

 

We had a glitch in the matrix overnight, and the article was accidentally moved back into "Draft". It should be fine now.

You may get a better response from the author if you leave a comment on the article.

Cheers

 

Maybe the member was like jpanhalt and he deleted all of his "intellectual content" when he left?

You're still pretty miffed about that I take it? I had to look up what you referring to; seems you've had a lot to say about it for a while now.

 

You're still pretty miffed about that I take it? I had to look up what you referring to; seems you've had a lot to say about it for a while now.

Hi,

Why what happened, i didnt even know he 'left' ?

 

Hello,

The link works for me.
It looks like the speaker is a 0.2 W 100 Ohms one:

View attachment 126428

That the link does not work for you, might be a permission problem.
@jrap , are the permissions for the articles correct?

Bertus

Hi,

Oh yes, thanks a lot. I did download that pic earlier before the article disappeared, but i did not notice that there was writing on the speaker because the picture was a little small. I should have zoomed in.

It does look like 100 ohms, which would definitely work for what i am planning to do.

Thanks again.

 

We had a glitch in the matrix overnight, and the article was accidentally moved back into "Draft". It should be fine now.

You may get a better response from the author if you leave a comment on the article.

Cheers

Thanks for fixing that. It works for me too now again.

One question though, why does it ask me to "log in" in order to comment when i am already logged in?

 

Hi,

Why what happened, i didnt even know he 'left' ?

He got ran off a few years ago. Stayed banned for a couple years IIRC. I think he came back after the management change but as of DEC2016 it looks like he left voluntarily due to politics. I think it was around the time of his original banishment that he deleted his posts.

 

Hi,

Why what happened, i didnt even know he 'left' ?

Like strantor said, he basically pushed the mods too far and they gave him a temporary ban. When the ban was up he came back long enough to find all of his old content/answers and then left for what he said was "for good". But came back after pulling the same thing at ETO.

 

You're still pretty miffed about that I take it? I had to look up what you referring to; seems you've had a lot to say about it for a while now.

Yeah, him and I got off to a rocky start and he never gave up on me, so this last time he pulled the, "I don't like the way the forum is going so it must change" crap, and just left.

 

Like strantor said, he basically pushed the mods too far and they gave him a temporary ban. When the ban was up he came back long enough to find all of his old content/answers and then left for what he said was "for good". But came back after pulling the same thing at ETO.

Hi,

Oh i see, well that's a shame when that happens.

I had some discussions with him too that i recall where he just refused to believe the information i was providing about some batteries, which was basically all over the web too (about the safety cautions concerning Li-ion cells and their charging). We went back and forth several times as he would not believe there was a safety concern

 

Hello again,

Before i begin my own teardown, it would help to know exactly what holds the ear pads on to the headphone shell. I dont want to tear the plastic as it is quite thin. It looks like there might be some trick to getting them off without damaging them, and that is key to getting inside of the two earpiece shells. The article just says to 'pull' up on them but i would to know what is holding them on first so i have some idea how much force is required and how much is too much.

I left a comment on the page, but no reply yet. Any way to contact Nick through PM or email?

Thanks again.