Dual impedance

[Jpswim]

Would it be possible to have two impedances for a headset, low impedance for wireless playing but a separate coil on the speaker with high impedance for use with a dac. With the use of a cord and amp it would be able to run fully but when unplugged it would switch to the low impedance. Also I feel the use of magnetic cord connects for the wired experience, the magnetic cords would also serve as an easy pull release of you forget to take the headset off. The use of a physical switch to swap between high and low impedance would be useful as well.  David Clark H10-66 would be an example of dual impedance but is used in aviation to match impedance of different radios

[emosun]

typically you wouldnt need this with higher end headphones as the headphones own onboard amplifier will be superior to any wired external amp. this may be required on cheap or low end headphones however. In the case of my bose headphones the onboard amplification is always superior to anything they can be plugged into.

[CTR640]

Only a handful of headphones does have that. If I'm correctly, Sony WH XM does have this and on some Sennheisers too. But why do you want/need this exactly?

David Clark headsets are on a different category.

[GoldenSound]

The impedance itself doesn't dictate how hard a headphone is to drive. The sensitivity is actually more important, and both have to be considered.

You can have a very high sensitivity high impedance headphone that'd take almost no power at all, or a very low impedance, low sensitivity headphone that requires a ton (such as the infamously hard to drive Hifiman HE-6)

It's very likely that trying to construct a dual-impedance design would inherently cause challenges for sound quality generally. And it'd make more sense to just have a more sensitive headphone that won't require too much power and therefore can be used wirelessly for long periods

[Jpswim]

My idea behind it would be a headset that can be used with a dac while at your main desk, but for a laptop to use the wireless low impedance which would conserve battery life. Thank you for all the responses, this was something that I thought about while stuck at work, but it kept me entertained with the concept for the day

[CTR640]

17 minutes ago, Jpswim said:

My idea behind it would be a headset that can be used with a dac while at your main desk, but for a laptop to use the wireless low impedance which would conserve battery life. Thank you for all the responses, this was something that I thought about while stuck at work, but it kept me entertained with the concept for the day

The battery life is something handled by the manufacturers themself. Not much we can do about it. But there are bluetooth adapters to use, maybe that's what you're looking for?

[ShearMe]

pretty sure that's not how that works

[Spuriae]

6 hours ago, Jpswim said:

The use of a physical switch to swap between high and low impedance would be useful as well.  David Clark H10-66 would be an example of dual impedance but is used in aviation to match impedance of different radios

I believe the headset's impedance switch controls the microphone, not the headphones. Military aircraft are designed to interface with a 5Ω microphone impedance, which often requires an adapter when plugging in a civilian headset.

36 minutes ago, Jpswim said:

My idea behind it would be a headset that can be used with a dac while at your main desk, but for a laptop to use the wireless low impedance which would conserve battery life. Thank you for all the responses, this was something that I thought about while stuck at work, but it kept me entertained with the concept for the day

Impedance itself doesn't have any significant effect on how power efficient a headphone is. A low impedance driver won't make a wireless headphone last any longer.

 

6 hours ago, Jpswim said:

Also I feel the use of magnetic cord connects for the wired experience, the magnetic cords would also serve as an easy pull release of you forget to take the headset off.

Magnetic breakaway headphone cables exist, but aren't very popular. The biggest problem with them is that unlike with charging cables, which normally have no change in the strain on them under normal circumstances, headphone connectors will have constant stresses applied to them as the user moves. On a charging cable it's easy to make the magnet weak enough to release under even a slight pull, but with headphones it's very difficult (if not impossible) to find a good balanced between too strong (such that it doesn't break away quickly enough on accidental tugs) and not strong enough (such that it comes off during normal use).

[H713]

The easiest way to accomplish this is with an impedance matching transformer. It's also an expensive and bulky solution, but it does work reasonably well. The main problem is that you need two of them, and if you want them to sound good, they're going to be expensive. 

 

Given where modern solid-state electronics are at, I don't necessarily see a real value. 

[Heats with Nvidia]

4 hours ago, H713 said:

The easiest way to accomplish this is with an impedance matching transformer. It's also an expensive and bulky solution, but it does work reasonably well. The main problem is that you need two of them, and if you want them to sound good, they're going to be expensive. 

 

Given where modern solid-state electronics are at, I don't necessarily see a real value. 

I second that. The other soultion would be multiple voice coils. But there you have a problem with the sound. You want the moving mass of the loudspeaker of the headphone to be as low as possible, because more mass means more energy is needed to accelerate all of this fast and this dampens the high frequency response and the impulse response. In short: It can be done, but these headphones wouldnt sound good, or at least worse than they could, if they only had one voice coil.