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Aviation headsets have Noise Reduction and a larger jack (1/4") than most PC headset counterparts (1/8"). But there are many excellent quality PC headsets with sound-proofing materials which eliminate external noise. So can I just plug in my PC headset using an adaptor? (Let's assume that I have a PC headset of equally good build quality, and comfort)

EDIT: What exactly are the functions of an aviation headset?

I've already looked at this topic, and this doesn't answer my question - I understand what Aviation Headsets do, but I'm asking (out of academic interest) whether they can be replaced with a superb quality headset for a PC, like for example, the Kingston HyperX Cloud II. If not, what exactly is different other than quality and noise cancellation? Again, this is for academic interest...

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    $\begingroup$ There is a company that will add a microphone to Bose noise-cancelling headphones so you can use them in place of more expensive headsets. I haven’t used them, but people on different blogs seem to like them. uflymike.com $\endgroup$ – JScarry Sep 4 '17 at 18:30
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Can you physically make it work? Yes. But you have to have an adaptor that fixes several compatibility issues.

Headphone impedance

Impedance is usually referred to in high and low range. Military headphones are low impedance, 19$\Omega$. Civil aviation uses 300$\Omega$, high impedance headphones. Impedance matching is not vital, but can cause some problems with sound quality. Using a low-Z headset with a high-Z output can cause distortion. A low-Z headset will also be more sensitive, so you would have to turn the volume down. You could run the risk of damaging the headset or your hearing if you have the volume up too far. The headphones you listed in the question are 60$\Omega$, which is somewhat of an in-between. There's no real standard, but low-Z are usually less than 32$\Omega$ And high-Z is usually above 100$\Omega$.

In the recording studio we considered high-Z headsets to be "universal" meaning that you could plug them in anywhere and they would work, but might be limited in volume. I used a set of low-z phones, since I could plug them into a line output and actually hear it. I was always careful to make sure volumes were turned down before I plugged them into the com boxes. They were pretty sensitive.

Microphone impedance

This will make a bigger difference than the headphones. Military systems use 5$\Omega$, low impedance mics. Civilian systems use high-Z, 80-300$\Omega$ amplified electret Mics. The headset you listed in the question lists 2.2k$\Omega$ which would be work, depending on how much amplification it has. Aircraft coms use a vox circuit to cut out noise that opens when you speak. Depending on whether there is a way to adjust the mic input the level may be too much or too little for the vox system. Too little and it won't open when you speak, too low and it will stay open and you will hear all the aircraft noise.

Phantom power

Electret mics require a power source to operate. They can either contain a battery or run off phantom power, which is a voltage supplied by the device it's plugged into. Some aircraft intercoms provide phantom power. I'm unable to find any standard voltage, but it appears the David Clark aviation headsets run on 8-16v. The standard voltage from a PC audio card is 5v. The headset you listed in the question shows that it requires 2v. I presume that, since it's made for PC use it's intended for 5v, but will operate as low as 2v. There's no way to know if 8-16v would overload it, so you would have to either adapt the phantom power or run it on a battery.

Connectors

Aviation mics have different physical plugs.

Most commonly the headset itself uses a 1/4" phono plug, wired the same way as older audio headsets with 1/4" plugs.

enter image description here

The microphones in aviation headsets are seperate and use a somewhat aviation-specific .206" TRS plug.

enter image description here

Helicopters and military aircraft use a completely different .281" TRRS plug for both headset and mic.

enter image description here

Airbus uses a 5-pin XLR connector for both mic and headset.

enter image description here

Judging from the fact that people have schematics posted on the web on how to adapt aviation headphones for non-aviation use, but not the other way around I would speculate that even the best non-av sets don't meet the challenges of aviation. Some of the physical design characteristics, such as the pressure exerted on the head pads, etc. are probably quite different from the non-av sets.

If you look at prices, aviation headsets run well more than twice the price of equivalent quality non-av sets. I'm sure some of that extra price is in design characteristics of the av sets. But, I also suspect that manufacturers will take the exact same sets, change a couple of resistors, put different connectors on them, add the word "aviation" to the box then add $500 to the price.


Images source

Aviation data found at Acousticon website

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  • $\begingroup$ So low-Z headset in high-Z output could damage both my hearing and headset itself, but when plugging high-z headset into low-z output, the volume just has to be turned up - right? Do you mean its safer to use high-z headsets, irrespective of the impedance of output? $\endgroup$ – ClobberXD Sep 8 '17 at 13:31
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    $\begingroup$ The only thing really "unsafe" would be if you put the set on then plugged it in without paying attention to the volume. The first Rinne somebody xmitted you could get an ear blasting. But I really doubt if an intercom would produce the kind of levels that would damage anything. It like when you start your car and find out you left the radio on too loud. Any well made set could handle that for a few seconds easily. Stuff that has been made in the last 25-30 years won't really be too sensitive to imp mismatch. But if you get on a J-3 with a 70 year old intercom it might be a different story $\endgroup$ – TomMcW Sep 8 '17 at 13:46
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    $\begingroup$ I read a couple of people in forums that said they had two mics with their headset that they could switch out. I'm supposing they were pilots that flew both military and civilian aircraft. So obviously the mic is the only real issue. If I had to guess, the real issue with the mic is that the hi-Z mic is amplified, so a military com wrong provide power and the input is not expecting an amplified signal $\endgroup$ – TomMcW Sep 8 '17 at 13:54
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    $\begingroup$ Speakers can be damaged in two ways, mechanically and thermally. Mechanical is where excessive power causes the coil to go outside it's physical limit and get stuck there. That usually occurs in big subwoofers. The more common problem is that when you put current through a coil it produces heat. If you put more current than it's designed for the will build up and start causing damage. That usually happens quickly, but if you do that repeatedly it would probably be cumulative. Speakers nowadays are pretty rugged, though. Just plain handling is toughest on them. The solder joints break $\endgroup$ – TomMcW Sep 8 '17 at 14:18
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    $\begingroup$ The Bose A20 is 160 ohm and they say it's good for all uses. Only the mic is different between lo and hi-Z. Damage to the com system seems highly unlikely to me. One of the quirks of phono type plugs is that if they're not plugged in firmly you can have a dead short between the connectors. If that would damage the circuitry they wouldn't use them. $\endgroup$ – TomMcW Sep 8 '17 at 15:01
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I just ran across this thread while investigating something similar, so my answer is almost 1 year old and will probably not be read. Anyway, one other very important factor is that Aviation headsets have noise cancellation in the MICROPHONE by using two openings on the mike, one in front to pick up the pilot's voice, and one on the back (or bottom) to pick up cockpit noises, namely the loud engine noise which makes conversation almost impossible (without headsets) to begin with. The noise cancellation picks up the engine sound in back and in the front, and cancels them since they are the same. The pilot's voice is not cancelled since it is mostly picked up in the front (when mike is positioned right). You might be able to build such a circuit and design a Mike boom, but time=money so it may be considerably more expensive to get this right in the long run, G. Tiggs.

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Yes you can use PC headsets if the right conversion plug is in place, and some work on the electronics is done. The frequency response of the average aviation headset is lower than that of an average headset that is used for listening to music, simce the aviation headset only has to reproduce the voice signals transmitted over the radio. A frequency range of between 400 and 4000 Hz suffices for voice transmission, most standard PC headsets can reproduce a much higher range.

Keeping the aircraft noise out is something that PC headsets are usually not designed for though. Aviation headsets clamp the rubber seals around the ears, not a standard PC feature. Active noise reduction works well for constant noise like air hiss, the ANR cannot suppress the noise effectively during frequency changes. A PC headset has no shielding for the cable, so electronic interference is not kept out of the signal path, and the engine sparks may show up in the sound.

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    $\begingroup$ I'd wonder if the squelch capabilities of the mics on those headsets can handle the cockpit noise. $\endgroup$ – Carlo Felicione Sep 4 '17 at 15:38
  • $\begingroup$ Thanks! BTW, what's up with the fuss being made about "impedance values"? Is it dangerous? $\endgroup$ – ClobberXD Sep 4 '17 at 18:24
  • $\begingroup$ @CarloFelicione What you're talking about is "vox" not squelch, although people tend to use them interchangeably. The vox is a function of the radio, not the mic. Some mics have an adjustment for output level which will affect when the vox system opens and closes. $\endgroup$ – TomMcW Sep 4 '17 at 21:46
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Sure you can. Just make sure when you make some quirky write up about the audio system not working, you let the A&P know you were using said headsets. I once worked on a "chronic" audio system problem for days not realizing the same crew member had been writing it up. Out of dumb luck, one of the guys I was working with ran into him at a bar and he was discussing how much he loved his Bose headsets. That sort of ignorance wasted whole days of our time.

Not all pilots have the luxury of altering their audio systems. The correct answer to this should be somewhere on the spectrum of "No" to "Situational."

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  • $\begingroup$ This is the argument I'm looking for! Why do you say that a PC headset ruins the audio system? How does it differ from an aviation headset in that aspect? $\endgroup$ – ClobberXD Sep 5 '17 at 7:58
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    $\begingroup$ It's not they will ruin the audio system. There may or may not be adverse effects from using them. If there were adverse effects, it would mostly be because of impedance matching issues as explained previously. The chief problem is that whenever you have a gripe about the audio system, I cannot effectively rule out YOUR headsets as part of the problem. Frankly, it's inconsiderate and rude to throw an unknown variable into the equation; leaving your A&P to work out in the elements during a holiday or kid's birthday only to find out that it was your PC headset causing the problem. DON'T DO THAT. $\endgroup$ – Frank Sep 6 '17 at 6:02
  • $\begingroup$ So impedance is the issue? Is there more to it? Just out of academic interest! Thanks. $\endgroup$ – ClobberXD Sep 8 '17 at 13:24
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    $\begingroup$ It doesn't necessarily damage the radios. It just might not interface well. The problem I was troubleshooting on a 727 about ten years ago was "Crackling and static on interphones happening intermittently throughout flight." It happened chronically, but also only about once or twice a week and there was a lot of focus on it. New Years Eve, while everyone was ringing in the New Year, I was trying to figure out what was wrong and it was about -5 outside. I wasted my entire night only to find out later that the guy who kept writing it up was using his own personal headsets. $\endgroup$ – Frank Sep 10 '17 at 3:58
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    $\begingroup$ Wow - that would've been terrible - sacrificing your family-time, for something that turned out to be disappointingly trivial! Thanks a ton - you were very helpful! $\endgroup$ – ClobberXD Sep 10 '17 at 6:53

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