Hi,received my gti1500 today,had a ace 250 before.run that for about 120 hrs.Had a big shock when i tried the gti.I think i have alot of learning to do.Its nothing like my ace,been practising with different coins.The gti didnt seem to respond as good to old copper coins and the silver gave a low trashy signal like a tin can.I guess i need to learn the sounds like the 250.Idont seem to hear that distinctive belltone on a coin like i did on the ace.I have it set on belltone.Anybody got any advice.Cheers.