Headphone questions - Help!

[danhughes]

Are expensive detector headphones worth it? Or are they like Monster cables - very pricey but no better field performance?

Is this Ratphones page: http://www.windycitydetectors.com/ratphones.htm full of doubletalk pseudoscience, or does it make sense?

I know a bit about electronics (I have an FCC First), but this explanation just confuses me. Somehow it reminds me of the so-called scientific proof that is used to promote LDLs.

Is a wide frequency range better for detector headphones, or a narrow range? Why? What is the optimum range?

Do detecting-specific headphones really have electronics that are different from stereo-listening headphones? Are home-stereo headphones as good for detecting as the headphones made especially for detecting (not considering ruggedness)?

I'm working on a podcast on headphones, and I'm getting different stories from different places and I suspect that many of the people who think they know what they are talking about do not. I count on this forum for accurate technical info - thanks in advance!

---Dan Hughes, http://thetreasurecorner.com

[pelanj]

Hello Dan,
from my experience, it does not really matter which headphones I have. I have tried earbuds, ordinary stereo, mono headset from a PC, large HiFi types, etc. All worked for me while knowing their limitations. Basicly, you must choose how much isolated do you wish to be from the surroundings - and then choose open or closed design. I prefer the open types or even one ear only - I like to hear what is going on, if there is a dog or other animal coming, etc.

The usual HiFi headphones do not often have a volume control. That is just about the main difference. For the beeps from the detector, any cheap headphone will do it. To get best results, get used to one particular headphone type. I would not buy any special "detectorist" headphones for any other reason than ruggedness, resistance to dirt and moisture. But why not get ten pairs of cheaper headphones for the same total price to last the same time? For me the biggest issue with headphones is the cable - sometimes you just step on in and pull it out or break the wire.

There are also some headphones with active electronics - however they will not tell you what the detector does not. A compressor/limiter for amplifying weak signals and attenuating strong signals may help someone a little, but a good detector does that anyway.

The page about RatPhones has some good info, some of it is conditionally (not generally) true, but no big nonsense.

[Reg]

Hi Dan,

Headphones are more of a personal matter as far as I am concerned. Now as a rule of thumb, the higher impedance headphones will be louder on a detector. So, a set of 100 ohm headphones will usually be louder than 32 ohm ones. This becomes important to people like me with bad hearing.

Now, as for the clarity, that is a matter of the type and size of speaker used. I have found plastic (mylar) speakers to be able to have a more mellow audio while paper cones can have a sharper raspier response.

I can't say what would work best for you, but I will say a person should try before buying. A 100 ohm set from one vendor may sound different than a set from someone else. So, I have never found a sure fire technique to select headphones.

Now, with that said, I like Koss units and even buy the cheaper ones such as the Koss UR 29's, which are very much like the Koss UR30's except without the curly cord. I will add a curly cord. However, over the years even Koss headphones have changed. I have some early ones that are sharp and raspy while the newer ones are a little more mellow.

Finally, some higher priced units are really good and may be the best for your hearing. However, again, I recommend trying them first.

Good luck in your search.

Reg

[danhughes]

Reg, I'm not looking for myself - I'm happy with my AudioPhone II. I'm putting together a podcast on headphones, and I want to get my science right. Hence the technical questions. I appreciate your help!

[Skippy]

Hi Dan
What you are really paying for with high-priced detecting 'phones is ruggedness and reliability. The remaining 'features' that are touted are needless sales talk.
For example - 'Impedance matching'. Inside the detector is an audio drive circuit that will make an 8 ohm speaker emit a very loud noise. Clearly, plugging any kind of headphone/earphone directly into this circuit will result in immediate perforated eardrums. Headphones need only 10 to 100 milliwatts, typically for optimum volume. So the manufacturers add a resistor in series with the headphone output, which, in combination with the headphone's resistance causes a significant volume drop. Typical resistances involves are: internal R=300 ohms, headphone resistance 25 ohms. There is no need to impedance match, you are not trying to get the highest volume, you're trying to reduce it from earsplitting to comfortable. Different manufactures/detectors have different internals so matching is not possible anyway.
Frequency response: The tone generated by detectors rarely goes above 1 kHz, it will be a sharp-edged square-wave, so having a frequency response up to 5 kHz is all that is needed to reproduce all that synthetic harshness.
Home stereo phones are generally too fragile, and they have no volume control. They may be more efficient than detecting ones, but that is not an advantage in this situation.
Regarding the Teflon/PTFE cable insulation: it is tougher, very heat resistant and thinner than the equivalent PVC. This doesn't make it better. The 'long soldering times' blurb is just rubbish. In fact, if you heat a wire joint too long, excess solder wicks further up the multistrand wire and leaves a significant length of the cable very brittle and inflexible, which will cause rapid failure. Never rely on the soldered joint for strength, you have to add strain-relief elsewhere, eg. grommets, clamps, glue.
Hope this is helpful

[danhughes]

Hope this is helpful

Exactly the stuff I was looking for! Thank you!