I was on the modification forum reading about building headphones hoping to fine something to be able hear faint tones. There are many times that I would look at my screen and see 70-80s flash by and not hear the tone made by those numbers.I PM (duggr) and he said pick up Koss UR29--Thanks Again---They came in yesterday and now I run my volume @1/3 on my F70--more battery life,maybe---When to a spot close to home were I have picked up silver and wheat's.With dis @ 2- SL-Sen@10-Thres@ -1--3H tone and notch 20 I hear a faint sweet tone and 68-74 on the screen swinging over the spot,moving the coil maybe 1'' L-R. Pinpoint 5'' and I pull out a 1906 wheat. I always wounder were those high numbers,I can prove that some are big iron.I think that I have passed up some nice finds because I could hear them---One thing for sure,working in a machine for 40+yrs and still working,not wearing any ear protection has no helped my hearing.-------after1-------