Clopen

[davidebond]

Hi. As you know, in topology there are open sets, closed sets and clopen sets, i.e. sets which are open and closed. This concept is not a problem for me. On the contrary, I am not able to understand the concept of a headphone semi-open. What does it mean?

Thanks and best,

Davide

 

[ZolaIII]

Hi. As you know, in topology there are open sets, closed sets and clopen sets, i.e. sets which are open and closed. This concept is not a problem for me. On the contrary, I am not able to understand the concept of a headphone semi-open. What does it mean?

Thanks and best,

Davide

It means similar to ported speakers, partly open for purpose of some sort of thing the frequency response.
Clopen really made me smile.
There are and open designs with additional side openings or port's if you wish and for the same purpose. Which are cold open not for their enclosure construction but because they go into external ear shell (earbuds) and don't have a seal from surroundings.

 

[davidebond]

Sorry, but I am not sure to have rightly understand...

 

[DVDdoug]

With a closed-sealed headphone (almost) no sound comes out of the back except sound that gets-through the case and earpads. Similarly, sounds from the outside are blocked from your ear, except again some sound leaks through.

An open headphone is completely open on the back and sound comes into the room from the back-side of the driver (speaker). You can hear outside sounds around you almost like you aren't wearing headphones, but the sound does have to go through the driver cone, etc., so it is slightly reduced. Of course if you are listening to an open headphone loud, outside sounds will be masked (drowned-out).

Semi-open is in-between.

...You MIGHT choose a semi-open headphone if you don't care if you can hear sounds around you or not, and you don't care about people around you hearing your headphones, but you like the sound of that particular headphone.

 

[isostasy]

With a closed-sealed headphone (almost) no sound comes out of the back except sound that gets-through the case and earpads. Similarly, sounds from the outside are blocked from your ear, except again some sound leaks through.

An open headphone is completely open on the back and sound comes into the room from the back-side of the driver (speaker). You can hear outside sounds around you almost like you aren't wearing headphones, but the sound does have to go through the driver cone, etc., so it is slightly reduced. Of course if you are listening to an open headphone loud, outside sounds will be masked (drowned-out).

Semi-open is in-between.

...You MIGHT choose a semi-open headphone if you don't care if you can hear sounds around you or not, and you don't care about people around you hearing your headphones, but you like the sound of that particular headphone.

To further muddy the waters, there are headphones described as 'closed' which might be better thought of as 'semi open' because although they are closed back, they have semi open front baffles. I think some Fostex, Denon, and E-mu designs are like this.

I agree that 'semi-open is in between' is about as precise as you can get. I find it fairly meaningless by itself. For example, the DT880 is described as 'semi-open', I think because it has more damping material behind the driver than a DT990. In my view it's still just open back however. Furthermore, DCA Expanse is 'open' but is said to use significant damping both before and behind the driver, to the extent it even feels like a closed back on the head. So where do you draw the line? It's more a category defined by exclusion I think.

After writing this I just found this post by oratory1990 which is almost exactly what I just put but much better: https://www.reddit.com/r/headphones/comments/6sqrys

 

[Vini darko]

Clopen
I have two sets called semi-open. Fostex t50rp and superlux hd681 ones closed the other is open.

 

[davidebond]

Ok. Thank first your accurate answers. I prefer the open headphone, because it is true the the noise outside disturb the listening, but they are more comfortable (for me) during a long listening. The closed ones make me claustrophobic. I don't think to have tried a semi-open headphone, but the hd 650 perhaps.

Thanks,

Davide

 

[isostasy]

Ok. Thank first your accurate answers. I prefer the open headphone, because it is true the the noise outside disturb the listening, but they are more comfortable (for me) during a long listening. The closed ones make me claustrophobic. I don't think to have tried a semi-open headphone, but the hd 650 perhaps.

Thanks,

Davide

The HD650 is definitely open and not 'semi-open' at all because not only does it have a completely open back with minimal damping, it also has an open front volume with breathable pads and the front and back volume aren't completely separate (there's holes and a 'screen' which does not entirely block sound). It's one of the best examples of an open headphone besides perhaps Grados which are basically just a driver in an open tube with foam on the front.

 

[davidebond]

I suspected it.

Thanks,

Davide

 

[egellings]

With a closed-sealed headphone (almost) no sound comes out of the back except sound that gets-through the case and earpads. Similarly, sounds from the outside are blocked from your ear, except again some sound leaks through.

An open headphone is completely open on the back and sound comes into the room from the back-side of the driver (speaker). You can hear outside sounds around you almost like you aren't wearing headphones, but the sound does have to go through the driver cone, etc., so it is slightly reduced. Of course if you are listening to an open headphone loud, outside sounds will be masked (drowned-out).

Semi-open is in-between.

...You MIGHT choose a semi-open headphone if you don't care if you can hear sounds around you or not, and you don't care about people around you hearing your headphones, but you like the sound of that particular headphone.

A problem with completely closed back headphones is that humidity quickly builds up in the ears, and that might make them itchy. It's best to take a break and air them out every so often while listening.

 

[davidebond]

You have right, but I loose the sense of unity of a work, like a symphony by Mahler or Bruckner.

Thanks,

Davide