[Thiws87]

Hello guys, i've just bought a pair of the sennheiser 555 headphones. They were sold as new and being 55ohms impendance. However they are unboxed and as far as i know there is a 120ohm version of these headphones... Therefore i'd like to know if there is any way to distinguish between the 120 and 50ohm versions. Because if they are the 120ohms version i'll be returning them since i don't want to use amps.
I think this is the most complete headphone forum over the internet, thus i hope you can assist me on this situation.
My best regards.

 

[Thiws87]

Someone help me plz, it's really important to me

 

[Thiws87]

anyone?

 

[Adda]

I once owned the 120Ohm HD555's and they where very easy to drive, so I wouldn't worry too much about it.

 

[winma]

Quote:

I once owned the 120Ohm HD555's and they where very easy to drive, so I wouldn't worry too much about it.

They are not that easy to drive IMO...which source you used? 

 

[Adda]

Quote:

They are not that easy to drive IMO...which source you used? 

 
I used a AudioTrak ProDigy 7.1 HiFi, a ProDigy Cube, a cheap KISS-db MP3 player and a lot of different soundcards (used them for like 5 years).
They sounded pretty much the same on all devices and had plenty of volume, this is from memory though, it was a while ago.

 

[Thiws87]

Well, anyway i suppose the 50ohms model would definetely sound better than the 120ohms one if both were driven without an amplifier...
 
I wonder if i could measure the impedance of the headphones with a multimeter without opening them. Is it possible?

 

[Adda]

Quote:

Well, anyway i suppose the 50ohms model would definetely sound better than the 120ohms one if both were driven without an amplifier...
 
I wonder if i could measure the impedance of the headphones with a multimeter without opening them. Is it possible?

I don't know how you measure impedance on a headphone, but as far as I know is not a trivial task.
Impedance is a complicated value and needs some rather sophisticated gear to measure.
 
Edit: oh and high impedance doesn't necessarily mean "hard to drive".

 

[Digital-Pride]

It's been quite a few years since Sennheiser has sold the 120 Ohm version of the 5X5 series.  So it is HIGHLY unlikey you bought one.  However, if you are still concerned, on the box where the headphone specs are located, you will see what the nominal impendence rating is. It should read 50 Ohms if not then you'll have a very rare 120 Ohm version.

 

[Thiws87]

Quote:

It's been quite a few years since Sennheiser has sold the 120 Ohm version of the 5X5 series.  So it is HIGHLY unlikey you bought one.  However, if you are still concerned, on the box where the headphone specs are located, you will see what the nominal impendence rating is. It should read 50 Ohms if not then you'll have a very rare 120 Ohm version.

Thanks for the info, it makes me more confident that i'll receive the right version. 

 


Quote:

Measure is easy. Try only ohmmetter. 55 ohm drivers is China, 120 ohm old original.
 

 
Tip is L, next R and last is ground.

Ok, Im not very expert on electricals but if it's really that simple to measure the impedance then i'll give it a try. I just need to find someone who has the ohmmeter (i think it won't be such a hard task though).
 
Thanks for all guys, your help shed light on my doubtful situation!
Cheers!