Stereo headphones on mono plug and ohms

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original45
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Stereo headphones on mono plug and ohms

Post by original45 »

[li[/list]been looking at headphones ,stereo to mono plugs and ohms.

From what little I can find it would suggest can stick a 3.5 mm stereo to mono adapter in to extension speeker hole and then get mono sound but equally both ear pieces from stereo headphones.

It too suggests its safe to do this and even though the ohms on a radio are 8 ohm speakers using 36 or 64 ohm headphones as its mono isn't a concern.
But could be a little quieter maybe.

Can someone advise if this is correct please.

Thank you
sonoma
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Re: Stereo headphones on mono plug and ohms

Post by sonoma »

I have a set of stereo head phones that I us on my computer and use a mono adapter as you mention to put them on my CB radio in the house when my wife is watching TV and does not want to hear the CB radio. they work just fine for me that way. I hear audio from both speakers. so it should work for you the same way.
original45
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Re: Stereo headphones on mono plug and ohms

Post by original45 »

Brilliant, do you know what kind of ohms your earphones are and if using larger ohm earphones could damage the radio.
Thank you
Tim
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Re: Stereo headphones on mono plug and ohms

Post by Tim »

The higher the Ohms the less power input the speaker will take, the audio out will become distorted, I think that's right in simple terms. This might help explain it.

https://www.lifewire.com/speaker-impedance-3134705
The Collector
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Re: Stereo headphones on mono plug and ohms

Post by The Collector »

It might make a difference in heating an amp up more in say stereo systems if the ohmage (is that a real word?) is different, say using 8ohm house speakers on a 4ohm car stereo, but I don't think it'd damage anything on headphones, it'd probably just sound a bit quieter as mentioned.

I could be wrong though so I'll now shut up ;)

However, I had 2x 8ohm speakers joined together into an ext.speaker jack on my Marko 777 CB for ages (for double-mono sound) with no issues.
paulears
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Re: Stereo headphones on mono plug and ohms

Post by paulears »

Most headphones have an impedance way above 8 Ohms - using an adapter parallels them which halves the effective impedance. As long as this is 8 Ohms or greater, your radio will be happy. The higher the impedance, the quieter they will be in practice. Ohmage have never been a real word, and large Ohms, is of course high impedance.

High impedance is typical in headphones because it is a useful feature - if they were 8 Ohms, and your radio is designed with enough power to drive a remote loudspeaker, then at 8 Ohms the headphone would be mega loud, and usually they'd have to have a series resistor to prevent overloading - the series resistor and the headphone coil impedance come to ....... the same kind of impedance as we have in modern headphones - neat idea!

If you use a speaker system with an impedance lower than the driving device is designed for, then it has to work harder, because 4 Ohms, for example is very close to a short circuit. A long length of thin cable has quite a high resistance because it's long and thin, so this is added to the speaker impedance - so the reason why two speakers that together should be too low, might end up OK. In professional PA systems, it's common for amplifiers to drive into a 2 Ohm load, and using really thick cable, the current can be pretty high. They are designed to cope with this. Often people get it wrong and amplifiers die. A few Watts from a radio isn't really going to tax the system - after all, shorting out speakers accidentally can be common, and they don't all curl up their toes and die!
original45
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Re: Stereo headphones on mono plug and ohms

Post by original45 »

Thank you all.I will now give them a try and will give the Mrs some quiet time from listening to static and chit chat in the background.

As ever I am much appreciative of your knowledge sharing.
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Re: Stereo headphones on mono plug and ohms

Post by The Collector »

I personally found that headphones became commonplace around 1983 when the bucketmouths (aka muppets) started swearing all over the airwaves and didn't give a sh**. "Buzby" had pretty much died a death by then or just couldn't cope with trying to police the airwaves. Youngsters used to be able to listen to people chatting whilst sat in their living rooms as a family, but as the language got worse, the heaphones started being used, or the radio got consigned to an under-the-stairs cupboard, spare room, or only got switched on when the kids had gone to bed.

Sad really, as they may have carried on the hobby for a few years more.

I used them myself back then so I wouldn't wake my parents up in the next room so easily whilst yapping at 3am :)
Tim
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Re: Stereo headphones on mono plug and ohms

Post by Tim »

Seems that nothing much has changed, even now some of the language is really foul.
original45
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Re: Stereo headphones on mono plug and ohms

Post by original45 »

Yes that's possible that they became popular due to foul language. I can remember my mom looking twice in the early 80 s for language.

Headphones work a treat . Thank you guys.

Thought I had dropped lucky today after buying a extension speeker from a ham guy at a boot sale .

Took it apart to check it's internal condition and noted it was stamped 2ohms on speeker back.

I'm guessing this is of no use on a 4 ohm radio because it's too power hungry and could distort on high volume.or am I wrong . As ever I'd rather ask and find out before trying it and doing damage
original45
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Re: Stereo headphones on mono plug and ohms

Post by original45 »

The language is still foul and choice of music whilst it's a little more up to date is still terrible.
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