If you are talking about a limiter that reduces the sound universally, such as a variable resistor, then it would be similar to headphone volume controls. Limiting the sound between the time it leaves the detector electronics and when it gets to your ears is basically the same, whether you do it in the cord or at each earcup. There are, however, limiters that will only reduce the level of "spikes" or extra loud signals. And those are incorporated into many of the "specialized" detector headphones, such as my Gray Ghosts. Others, such as DetectorPro's Nugget Busters do not have the limiter. In fact, other than color, the only difference between the Original Gray Ghost and the Nugget Buster is that sound limiter.
As to raising the Threshold when lowering the volume.......remember, Threshold isn't a number. It is a level. And people could require different levels, depending on their hearing. My point in the earlier post was, if you are running your audio at full bore and hear the threshold at a 5, then when you put an inline limiter into the mix, or if you turn your headphone volume controls down, depending on how far you restrict the sound, you may have to raise the Threshold up in order to hear it. Honestly, I don't know as I've not tried it. But it makes sense to me that if you restrict the audio level to the headphone speaker output in an effort to reduce the volume, you are restricting all audio sounds that travel to those headphone speakers.
As to missing some targets with your volume lowered, I am convinced it will. That is why I run with full volume and use quality headphones with a sound limiter. If you hit upon a target with full volume,with what some refer to as a faint tone, it only makes sense to me that a lower volume level could reduce your chance of hearing it.
I have several sets of headphones. Those I use most are my Gray Ghost NDTs. Other than being extremely comfortable, blocking out most ambient noise, having a long coil cord and 90 degree plug, I prefer them for their dual volume controls and the fact they have a stereo/mono switch. This allows me to use them with any brand of detector. My backup set is the Original Gray Ghosts, which is basically like the NDT except is has a single volume control and doesn't come with a spare cord. I've had both sets for years and years. After about 4 years, the pads were getting hard and starting to check. I contacted Detector Pro and got a new set of pads for around $10. Good as new! JMHO HH Randy
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