Thank you all for your time and attention. I'm a budding audio enthusiast and looking for answers and suggestions.

I own an extremely low end stereo system (Aiwa) and I usually listen to it on headphones. The music is piped in from my PC with no amps or other equipment attached (will soon upgrade to Creative X-Fi).

In the past, my headphone purchases have been in the sub $100 range. After a few months, the cans just die. I have gone through Koss, Panasonic, Sony, Radio Shack. The Koss lasted the longest at 1.5 years. After such disappointment, I started getting critical about these matters and surmised that a low impedance rating was causing my cans to get fried. You should know that I listen at the highest volume level possible.

* Is the problem the low impedance, or the fact that sound is coming in to the audio receiver from the PC?

* Will a set of Senn HD 650s, with an impedance rating of 300 Ohms solve my problem?

* Would it be prudent to connect the very dear Ultimate Ears UE 10 Pros to such an uncouth system?

* Would adding an amp to the mix help matters? (maybe "condition" the juice before it gets to the cans?)

Obviously, I am considering the Senn 650 (UE would be for ipod), and such being the case, will accordingly upgrade my equipment. I am simply wondering whether a higher impedance rating will prevent my cans from getting fried again.

Thank you in advance for any advice or suggestions you may offer.

If this question, or a similar one has been previously answered on these forums, kindly point to it.

Best Regards,
33O

I think that is the problem.

High impedance headphones won't stand more input power per design.
But in god's sake please use them - they will protect your hearing because at a certain input voltage they are not as loud as these 30-Ohms-thingies.
Please be more gentle to your ears. You only have 2 of them. The inner ear will be irreversibly damaged by excessive loudness.

Lots of people are bent on self-destruction. Each decides on his or her own pathway to hell. After all, if you don't have freedom to make the wrong choices, you don't really have much freedom.

There is no reason to expect headphones to be exempt from the limitations of speakers. Driving an insufficient amplifier into clipping will destroy most much faster than driving them very loudly with a powerful amplifier that does not clip. This is not to say that enough power can't immediately destroy speakers or headphones, but with a powerful amplifier you will at least know it is because you just burned out the coils by turning them up too far, similar to setting a match to a puff of cotton.

All this is to say that your headphones might do significantly better with a decent headphone amplifier. The headphone output on many stereos, particularly inexpensive ones, is rather limited and might be over driven with your listening preferences.

Consider another possibility, however, just in case you haven't already; "the cans just die" isn't very informative, after all. In general, headphone cables are much more prone to breaking than the headphones themselves. If you are not obsessively careful with them, flexing at the cable-to-headphone or the cable-to-jack connections breaks the wire or, in a few cases, loosens the solder connection. These breaks are most often not visible from the outside.

In most cases this only effects one side, unless you go on using then one-sided until the other side's wire also breaks.

Most amps can't deliver enough power to blow headphones since the headphone output generally has resistors to reduce the power to a fairly low level. Not to say it's impossible though. If they can last a few months rather than a few minutes it would be more likely that wires are breaking through constant bending. Higher impedance phones will reduce the chance of blowing, but it'll do that by reducing the power available and hence the volume.

If you're concerned about your hearing surviving though, it sounds like you need to turn it down!

But the freedom to choose between wrong choices isn't much freedom either!

Indeed. I had a set of Sony ("studio") headphones for some twenty years, the only thing that eventually killed them was a mouse which chewed them up.

That makes no sense at all. It is complete freedom of choice. Quite aside from the fact that 'wrong choice' is, in most cases we might be considering, a value judgment.

Now if you are talking about presenting someone only with choices that are 'bad', and suppressing other options, well preventing someone from making 'good' choices is no different than preventing them from making 'bad' choices. In either case you (whoever the you is that is being coercive) are the oppressor.

And yes, there are special circumstances such as young children and people truly very mentally deficient.

Thank you all, lads. I have noticed that with the Shure E2Cs, I don't turn the volume as loud as over the ear cans. So, the only sensible thing is to turn it down, and keep it down.
One thing that makes a lot of sense is the cord breaking, as AndyH suggested; the reason for this is that it was usually it was one side that went silent. In retrospect, I didn't take very good care of them, probably because they weren't reference-grade investments.

It's all been very helpful, so thank you once again for your time and thoughtful responses.

33O