Design differences between open and closed headphones?

[rickles]

The title says it all. Clearly, closed headphones are not simply open headphones with solid ear cups. (We've all covered a pair of open headphones with our hands, and heard the effect). I'm curious to know a bit more about these designs technically, and didn't manage to find a good thread, or page on this. I'm sure however they exist somewhere! TIA!

How do the designs vary from a technical perspective?

Are all drivers suitable for open or closed use?

Why are most headphones considered to be top of the line seem to be open designs?

Are there times other than isolation where closed designs can be superior?

 

[ProtegeManiac]

The title says it all. Clearly, closed headphones are not simply open headphones with solid ear cups. (We've all covered a pair of open headphones with our hands, and heard the effect). I'm curious to know a bit more about these designs technically, and didn't manage to find a good thread, or page on this. I'm sure however they exist somewhere! TIA!

How do the designs vary from a technical perspective?

Hands likely don't have the same acoustic properties as whatever manufacturers line sealed earcups with, ie, it's not just maggots and decay and rust that makes bacon and pork hocks a bad and impractical idea vs Dynamat in car doors and fiberfill in speaker cabinets.

And manufacturers who make the drivers likely make different drivvers with Thiele-Small Parameters (this is the kind of stuff that is listed for raw drivers like car subwoofers and much of the stuff on Parts Express that tells you how big the cabinet and port should be) for sealed cups.

Are all drivers suitable for open or closed use?

To a point, yes. But depending on the T/S parameters it might have to be a gigantic earcup with a lot of acoustic dampening to slow the backwaves down for the difference to come down due more to isolation than the driver's movement getting affected. VIce versa, not as much...with speakers drivers with T/S parameters that allow it to work well in closed or ported enclosures tend to make them roll off early and lack dampening ie driver control when operated in an open air environment and you end up with a lot of driver distortion.

Why are most headphones considered to be top of the line seem to be open designs?

So they won't have to account for the effects of the soundwaves coming from the back of the driver diaphragm and just design the driver pretty much to operate as it does on a bench with a grill on the rear.

Are there times other than isolation where closed designs can be superior?

More of a thing with speakers than headphones AFAIK. Most freeair that are good have to be large to have a lot of low end, but that limits response range at the top end or adds driver distortion; the open design on a speaker also risks more interference as the whole speaker is in front of the listener rather than have the front of the drivers firing into the listener's skill with the backwaves going in the opposite direction. With speakers you can use a sealed enclosure to dampen and control the movement, and a port can also be used to extend the bass response.

 

[PaganDL]

@ProtegeManiac,

Can't say it better than that, aside from your car analogies, like your food references too

Keep up the good work !

Though I will add one thing, sound tuning is also another factor between open & closed @rickles should consider in those design differences...

Hope you have a great day !

 

[ProtegeManiac]

@ProtegeManiac,

Can't say it better than that, aside from your car analogies, like your food references too

 

[SonyFan121]

The level of thought that goes in to the design of some headphones (not all) is very reassuring. A closed headphone can sound very like an open headphone, it all comes down to the shape of the cups and dampening material used inside them. The best examples that i've heard of closed headphones sounding like open headphones would be headphones such as Astell & Kern T5P, Beyerdynamic T70, and Denon AH-D5000 ( AH-D5000 especially when paired with a good amp, but the T5P and T70 sound like open headphones without needing amped).