[nukaidee]

Hello,

I read many topics about livewires on these forums and it seems like other people have same issue I experience. My livewires are very hissy in some players and therefore I need an impedance adapter. I wish to create one with 50ohm impedance. is it as simple as creating a "headphone extension" mini male to mini female with 50ohm resistor inside? which type of resistor?

thank you

 

[Steve Eddy]

Quote:

Originally Posted by nukaidee /img/forum/go_quote.gif Hello, I read many topics about livewires on these forums and it seems like other people have same issue I experience. My livewires are very hissy in some players and therefore I need an impedance adapter.

Earphones and headphones don't hiss. Any hissing you hear is being produced by the gear you have your earphones or headphones plugged into. An impedance adapter isn't going to help you in that regard.

The added series impedance will act as an attenuator reducing the hiss, but it will also reduce the music signal by the same amount so there's really no net gain.

Quote:

I wish to create one with 50ohm impedance. is it as simple as creating a "headphone extension" mini male to mini female with 50ohm resistor inside?

Yeah, it is ultimately as simple as that, but if your problem is hiss, it's not going to help you any I'm afraid.

k

 

[nukaidee]

ah. i see. then it is probably the source. but if i also have a complaint that 10% on one of my music players (the minimum) is too loud for a quiet room, then this will solve the issue?

 

[Steve Eddy]

Quote:

Originally Posted by nukaidee /img/forum/go_quote.gif ah. i see. then it is probably the source.

Yes.

Quote:

but if i also have a complaint that 10% on one of my music players (the minimum) is too loud for a quiet room, then this will solve the issue?

I'd need to know more about the system you're talking about here. Since you say "too loud for a quiet room" I assume you're talking about a system with loudspeakers, and not headphones?

k

 

[nukaidee]

nono, just inside a library, I find my IEMs loud enough to be slightly annoying when I am studying.

anyways, I am guessing i should be getting low tolerance (1%) resistors for better symmetry between both channels? which kind of resistor? it seems that metal oxide seems to be a popular choice in audio?

 

[Steve Eddy]

Quote:

Originally Posted by nukaidee /img/forum/go_quote.gif nono, just inside a library, I find my IEMs loud enough to be slightly annoying when I am studying.

Ah, ok.

So what is it exactly that your IEMs are plugged into that doesn't allow you to adjust the volume to any lower level?

Quote:

anyways, I am guessing i should be getting low tolerance (1%) resistors for better symmetry between both channels? which kind of resistor? it seems that metal oxide seems to be a popular choice in audio?

Yes, you'd want to use 1% or better. And unless tastes have changed, metal film is generally more popular than metal oxide.

k

 

[nukaidee]

well its currently plugged into either my phone or an old creative player until my amp3 arrives. are there any stores that sell headphone adapters online? i couldn't find any impedance adapters =(

 

[Steve Eddy]

Quote:

Originally Posted by nukaidee /img/forum/go_quote.gif well its currently plugged into either my phone or an old creative player until my amp3 arrives.

Ah. And neither of those allow for the volume to be turned down beyond a certain point?

Quote:

are there any stores that sell headphone adapters online? i couldn't find any impedance adapters =(

Not that I'm aware of.

And an impedance adapter isn't really what you'd want for your purpose which is an issue of attenuation. So you basically need to create a voltage divider, which is how a typical volume control works, only the amount of attenuation will be fixed and not variable.

What's the rated impedance of your Livewires?

k

 

[nukaidee]

I'm not sure. I think a consensus on these forums was about 22 ohms?

 

[Steve Eddy]

Quote:

Originally Posted by nukaidee /img/forum/go_quote.gif I'm not sure. I think a consensus on these forums was about 22 ohms?

Ok.

So if we make that assumption and your phone and player are able to handle that 22 ohms, then you can make an attenuator like illustrated below.

Try an Rx of 10 ohms to start. If it's not enough, make Rx lower in value until you get the level you want.

k

 

[boomy3555]

Quote:

Originally Posted by nukaidee /img/forum/go_quote.gif well its currently plugged into either my phone or an old creative player until my amp3 arrives. [size=small]are there any stores that sell headphone adapters online? [/size]i couldn't find any impedance adapters =(

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