Adapt Sennheiser headphones to speaker wire connections

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I recently bought a Samsung home theatre system that has no AUDIO OUT connections other than those for speaker wires.

Is there an adapter / converter that will allow me to go from speaker wire connections to a headphone jack? I have Sennheiser headphones.[/I][/I][/B]

Although I am a good builder, I am not a designer, and certainly not in the class of those who participate here. Any suggestions / solutions will be greatly appreciated. If anyone has a solution they market, I'l like to know that as well.

Thanks,
 
If you google 'Speaker output to headphone adapter' you will come up with a bunch of suggestions.
Probably the best/simplest (you can eliminate the switch if you have speaker 'B' connection available on your amp) is Rod Elliott's: Headphone adapter.

There is also a pic from Grado floating around the web which shows a simple resistor voltage divider built on a dual banana plug.
 
First you have to be sure the black speaker terminal is connected to a common ground and not something else. An ohm meter should be able to test for this the reading between any two black jacks should always be 0 or very close to it. Try this first with the power off then with it on.

Use a 1000 ohm 2 watt resistor to a 47 to 100 ohm 1/4 watt resistor to make a voltage divider to drive your headphones. The 1000 ohms connects to the red speaker terminal on one side to the 47 to 100 ohms on the other. The other end of the 47 - 100 ohms goes to the black terminal. The shield of the headphone jack goes to any black terminal. The tip goes to the left speakers resistor junction. The ring goes to the rights.
 
the above is an afterthought imo, damping will be terrible and this is exactly the sort of 'headphone output' tghat is often seen on amps to fill out the specs and that gives headphones a bad name. if it must be a passive solution a transformer would be a better solution here, one that provides suitably low output impedance. not dissing here, its a simple solution that will 'work' but its sound will be far from what the headphones and amp are capable of
 
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the above is an afterthought imo, damping will be terrible and this is exactly the sort of 'headphone output' tghat is often seen on amps to fill out the specs and that gives headphones a bad name. if it must be a passive solution a transformer would be a better solution here, one that provides suitably low output impedance. not dissing here, its a simple solution that will 'work' but its sound will be far from what the headphones and amp are capable of

The headphones mention are between 600 to 2000 ohms, so damping factor from a 47 ohm resistor will be at least 12 up to 42! That is why you don't just use a series resistor.

Of course you can scale down to a 10 ohm series resistor and .47 ohms for the shunt. That would give you damping factor to a new high.
 
haha ok sorry i missed that they are up to 2k0 impedance. i still think a transformer is a better solution, though more expensive. most headphones are nowhere near this though and you still see this method used on speaker amps and preamps to fill out the specs. it will work in the above case, probably pretty well and cheap to try out, so its a good recommendation; but its a pretty crappy headphone cct imo
 
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haha ok sorry i missed that they are up to 2k0 impedance. i still think a transformer is a better solution, though more expensive. most headphones are nowhere near this though and you still see this method used on speaker amps and preamps to fill out the specs. it will work in the above case, probably pretty well and cheap to try out, so its a good recommendation; but its a pretty crappy headphone cct imo

A good transformer is $100 ea. It is actually much cheaper to build a high quality headphone amplifier.

But you did raise a good point about damping.

The other issue is safety. If you don't use some sort of attenuation you can blow out the headphones. They should be designed to destroy themselves before they damage your hearing. Of course if they don't you can instantly damage your hearing permanently.
 
indeed, i'm just talking about quick and easy components to drop in the output with little fussing about, of course a decent yet simple headamp cct like EUVL's DAO follower would be preferred.

headphones arent designed that way though, your hearing will be damaged long before you blow the drivers on todays high end headgear. for instance my jh13 custom in ears are 119db and 26ohms at 1khz or there abouts, ears will clip long before they do. these are some of my preferred headphones and sound brilliant, all the amps i have built for them are unity gain or less (at balanced 3vrms output) and this is more than enough. some would say they dont need an amp, i disagree, portable players and the headphone outputs on commercial gear are just not designed to cope with 6 driver in ears that present less than 8r at some frequencies. they dont need volume from an amp, but they sure sound better with one.
 
First you have to be sure the black speaker terminal is connected to a common ground and not something else. An ohm meter should be able to test for this the reading between any two black jacks should always be 0 or very close to it. Try this first with the power off then with it on.

[...]

The headphones mention are between 600 to 2000 ohms, so damping factor from a 47 ohm resistor will be at least 12 up to 42! That is why you don't just use a series resistor.
Good call on the common ground. The alternative would be to rewire the headphones to use a 4 pins xlr with seperate grounds.

600 to 2K ? Did the OP actually specify the headphones he would use ? Today, Sennheiser produces headphones in between 32R and 300R (nominal).

Here is Grado's suggestion:
 

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