[imran27]

Pretty old thread but I just read it and feel like I should add something to it.
 
Z -> Impedance, assume that I have an amp that can provide any voltage and any current - ideal amp & same sensitivity
 
Low-Z Headphones:
 
- Need less voltage to reach a particular sound level (dB)
- Draw more current (hence power) at a particular voltage level, resulting in heating of amps (If 16 ohm draws 62.5mA at 1V then 8 ohm will draw 125mA and 1.2ohms will draw 312.5mA, pretty huge isn't it?)
- If using on a portable or any other non-ideal amp, the frequency response will change a little bit due to different loading on the amp due to different impedances at different frequencies
 
High-Z Headphones
 
- Need more voltage to reach a particular sound level
- Draw less current at a particular voltage level resulting in lower loudness (250 ohms will draw just 4mA of current at 1V, 4mW for 100dB/mW will give 100.6 dB. Not all mobile phones produce 1V)
- If using portable amp they will the frequency response f headphones will largely be unchanged due to minimal or negligible loading effects at all frequencies
 
Remember, frequency response itself is in vague sense the different impedances at different frequencies. If headphones are bass boosting then they have lower impedance at bass frequencies and hence will have significant loading effecting on a portable amp or your ipod (ipod afaik is ~5 ohms out-Z).
 
When the output impedance of a voltage source is greater than 0 ohm then any load impedance will reduce the voltage output. Assume a 1V open circuit output voltage which will reduce to 0.762V when connected to your iPod, think what will happen when the impedance is less at low frequencies! That is why we see a good boost in headphones response via an amp like E6 that has less than 1 ohm out-Z. There low impedance at boost frequencies (be it bass or treble or mids, it doesn't matter) will not cause significant loading and output voltage will retain it's intended leve produce exactly what headphone was tuned for.
 
That is why high-Z headphones sound different than low-Z ones. If someone has Both 32 ohms a.w.a 80 or 250 ohm versions of Beyerdynamics then they can try it out. Just remember to adjust volume to produce same loudness level on both impedance versions. They most probably will sound different with high-Z ones giving more pronounced boost to intended regions

 

[freecitizen]

Hi, there seem to be a lot of technical discussion here about the difference between low Z and high Z headphones. However, the more pertinent question or answer is how different do they sound. Here is my take, I have a Philips SHP 8900 and a HD 600. The former is 32 Ohms and the latter 300 Ohms. Straight out of an amp socket, a low Z unit sounds louder; the high Z unit need a higher turn of the knob to sound as loud. I have a FiiO E12. I put it between my amp socket and my cans. This is where I here the difference. Again, the low Z sound louder at a low setting of the knob. However, the low Z unit sounds "loose". As if the residue frequencies kept going when it is meant to stop. On the other hand, the high Z unit sounds tighter. Sounds more natural. Good tests are piano pieces and vocals.

Tim

 

[angularmo]

Newbie question,
Are high-impedance headphones safer on the ears in terms of less ear pressure for the same volume compare to lower impedance cans due to a stiffer driver?

 

[JK1]

It seems like the higher impedance headphones use a smaller gauge of wire for the coil, and the lighter voice coil means less exotic materials need to be use to get good sound from the diaphragm.

 

[Currawong]

Newbie question,
Are high-impedance headphones safer on the ears in terms of less ear pressure for the same volume compare to lower impedance cans due to a stiffer driver?

No, no difference at all. The only way headphones can be "safer" is not to listen too loud with them. 

 

[Hitec]

I always thought it was just a heat thing.  2 ohm cable, or circuits will get waaay hotter than 8 ohm, and so more distortion will be introduced.
In car audio, we use to run the amps in parallel to get a lower ohm so that we can get more current to the subs, but in turn the cable got hot, and sometimes melted the jacket on the speaker wire..

 

[Hitec]

  It seems like the higher impedance headphones use a smaller gauge of wire for the coil, and the lighter voice coil means less exotic materials need to be use to get good sound from the diaphragm.

In comparison, the higher ohm can use a smaller wire, while the lower ohm should have the larger wire.  Low ohms mean, hotter wire.  High owns mean cooler wire.  The hotter it gets the larger the wire needed to keep it cool, and keep the distortion down.  Is that in concurrence with what you are saying?  

 

[Hitec]

  Hi, there seem to be a lot of technical discussion here about the difference between low Z and high Z headphones. However, the more pertinent question or answer is how do different to they sound. Here is my take, I have a Philips SHP 8900 and a HD 600. The former is 32 Ohms and the latter 300 Ohms. Straight out of an amp socket, a low Z unit sounds louder; the high Z unit need a higher turn of the knob to sound as loud. I have a FiiO E12. I put it between my amp socket and my cans. This is where I here the difference. Again, the low Z sound louder at a low setting of the knob. However, the low Z unit sounds "loose". As if the residue frequencies kept going when it is meant to stop. On the other hand, the high Z unit sounds tighter. Sounds more natural. Good tests are piano pieces and vocals.
 
Tim

Agree.  This is exactly, how I felt with 4ohm car stereo.  Some created ohm circuits in their cars and used modified equipment to drive the circuit.  It seems that the speaker control, is smoother, more precise, and has less distortion.  .  ..but amps seem so much cleaner today...

 

[Popeye7]

You have no idea what you're talking about.

I wonder if you just made this up.

Low impedance headphones will not "blow up" if connected to a "powerful" setup.

Impedance is important related to the output impedance of the amp.

Low impedance does not mean something is easy to drive.

Google the Apogee Scintilla speaker. It has a 1.2 Ohm impedance. So if low impedance means easy to drive, then how come the Scintilla has a terrible reputation for overheating and literally melting lesser amps?

Impedance has to be considered along with an amp's output power, an amp's output impedance, and the headphone's sensitivity. You take the output power, consider how the output impedance and headphone impedance interact (there is a formula for this) and then you get the amount of power that comes through. Use that resulting power figure with the headphone sensitivity and you can calculate how loud the headphone will get.

If you only have the headphone impedance, you cannot call it a "tough" or "easy" load. That's like saying that x + y + z = n. If x is 3, find z. You can't. There isn't enough information.

When it comes to headphones, you generally want an output impedance lower than the headphone impedance. This is called the "Damping Factor"; look it up if you don't know what it is. Generally speaking, only solid state and output transformer-coupled tube amps have a low output impedance. OTLs have a high output impedance. Do not listen to OTL manufacturers when they say it will drive "anything," that's not true. They will make sound with anything, but an output impedance higher than the headphone impedance loses control of the bass. The only commercial OTL that does low impedance is the Zana Deux, and that's mostly because of its 6C33C tubes. If you don't see 6C33C tubes in an OTL, it probably has a high output impedance.

"...the Apogee Scintilla speaker. It has a 1.2 Ohm impedance. 
So if low impedance means easy to drive, then how come the Scintilla has a terrible reputation for overheating and literally melting lesser amps?"
 
Because it's a 1.2 Ohm load and would be extremely hard on even some high quality amps.
 
A headphone with a low impedance relative to the amp output impedance would probably not give the best performance. My HiFiMan HE400i were not good with my <60 Ohm tube headphone amp. That thing wants to see, (rule of thumb) at least, not less than 250 Ohm. 35 Ohm is too low. Bass is bloated, muddy and distorted, and the midrange all but disappears. To run those headphones I would have had to insert something between the amp and cans to make the phones look like something with higher impedance, which I was unable to easily find.

 

[Milo1230]

Very old Thread I know. But I recently bought a Sound Blaster AE-5 for my new rig and I love it. I've also had some dope Audio Technica A900xs that I have been using. Taken from Sound Blasters' Site:


Xamp Discrete Headphone Amplification
The Sound BlasterX AE-5 is the first sound card to feature Xamp, our custom-designed discrete headphone amplifier. Each audio channel is individually amplified, allowing the AE-5 to deliver a whole new level of pristine audio fidelity in an unaltered lossless model to each earcup regardless of demand. The ultra-low 1Ω output impedance drives 16-600Ω headphones perfectly.



So my main question is. If my A900x's are 42 ohms. Do I have a chance of damaging burning out my headphones? The reason why I ask is because when I DID use the headphones with my new soundcard, my left ear went completely out in my headphones a few weeks ago. It started as a fading out in out etc. at first then completely went out.. I tried messing with the bit rate a little doing 32bit/48khz then 24bit and reading back up on these fourms I see, 16bit/44.1 is the "proper" way to go.. Shi* I have no idea anymore, I just want these headphones and soundcard yo.. I am I missing something here??! Why would Sound Blaster say 16-600ohm if that isn't the case is my question? Do I need Stronger cans'? I need some help y'all~ haha

 

[serman005]

To me, it is not so much a low-Z or hi-Z situation as it is a matter of the damping factor. Low impedance headphones are sometimes very, very difficult to drive.

 

[rutter]

And high impedance headphones are sometimes extremely easy to drive- HD 650. Sensitivity is a huge factor.

 

[jupitreas]

Very old Thread I know. But I recently bought a Sound Blaster AE-5 for my new rig and I love it. I've also had some dope Audio Technica A900xs that I have been using. Taken from Sound Blasters' Site:


Xamp Discrete Headphone Amplification
The Sound BlasterX AE-5 is the first sound card to feature Xamp, our custom-designed discrete headphone amplifier. Each audio channel is individually amplified, allowing the AE-5 to deliver a whole new level of pristine audio fidelity in an unaltered lossless model to each earcup regardless of demand. The ultra-low 1Ω output impedance drives 16-600Ω headphones perfectly.



So my main question is. If my A900x's are 42 ohms. Do I have a chance of damaging burning out my headphones? The reason why I ask is because when I DID use the headphones with my new soundcard, my left ear went completely out in my headphones a few weeks ago. It started as a fading out in out etc. at first then completely went out.. I tried messing with the bit rate a little doing 32bit/48khz then 24bit and reading back up on these fourms I see, 16bit/44.1 is the "proper" way to go.. Shi* I have no idea anymore, I just want these headphones and soundcard yo.. I am I missing something here??! Why would Sound Blaster say 16-600ohm if that isn't the case is my question? Do I need Stronger cans'? I need some help y'all~ haha

This doesn't sound like it has anything to do with impedance at all. Your cans have an impedance of 42 Ohms and the sound card should have no problem driving them. You can't 'burn out' headphones with an impedance mismatch, you could only perhaps damage them if you play them too loud. With this said, damage from that would sound completely different - you'd likely begin to hear the drivers 'fart' due to the physical damage they received from too much power. But frankly, cans nowadays are built in a way that makes this very unlikely.

My guess is that the issue is either with the soundcard or with the cables inside the headphones. The left-ear cable could have become loose or damaged and this is why sound isnt getting through to the left driver. It could have also (unlikely) oxidized. The plug itself could also be damaged. Just replace the cables and all should be good. Alternatively, the sound card could be faulty. It could be as simple as a buggy driver or the sound card hardware itself could be faulty. Try updating the driver and if that doesn't fix it, I hope you still have warranty for the card.

 

[Milo1230]

This doesn't sound like it has anything to do with impedance at all. Your cans have an impedance of 42 Ohms and the sound card should have no problem driving them. You can't 'burn out' headphones with an impedance mismatch, you could only perhaps damage them if you play them too loud. With this said, damage from that would sound completely different - you'd likely begin to hear the drivers 'fart' due to the physical damage they received from too much power. But frankly, cans nowadays are built in a way that makes this very unlikely.

My guess is that the issue is either with the soundcard or with the cables inside the headphones. The left-ear cable could have become loose or damaged and this is why sound isnt getting through to the left driver. It could have also (unlikely) oxidized. The plug itself could also be damaged. Just replace the cables and all should be good. Alternatively, the sound card could be faulty. It could be as simple as a buggy driver or the sound card hardware itself could be faulty. Try updating the driver and if that doesn't fix it, I hope you still have warranty for the card.

I appreciate everyone answering me here : ). . Yeah I bought these guys in May'ish brand new, but from ebay no doubt. So if anything I'll have to go thru the company if my new Headphones decide to be grumpy (I WAS going to re-buy them, but kind of thinking about the DT 880 Pro 250ohm version's). Dude, yes! thats exactly what I was thinking. I had someone from IGN trying to tell me otherwise, but wasn't 100% happy with his answer. If I am being honest, before the audio cut out between both ears and the inevitable cut out of the left ear.

From what I remember there was at one point a high pitch squeal which came from my left ear. And there was defintley some EMI noise issue that my sound card was picking up on (crackling, popping noise) - there was also a weird issue where EVERYTIME I would try to plug my headphones in the front audio port (thats where I would have the least amount of EMI resistance) I would get a small bit of a 'shock'.. I dunno if any of that corresponds with the drivers 'farting' (love that term *t00t*). Driver is up to date on my soundcard, but I was thinking about rolling it back to see if that does anything? When hooking the A900x's to my phone I get the same issue, I honestly think its the wiring of the cable etc. Shi* is pretty old haha, about 4-5 yrs now.

 

[Milo1230]

bump