With a VCO in all-metal some of them sound like a mix of finches, doves, warblers, ducks and geese with some steam whistle in the background. The Tejon in VCO mode is very interesting indeed.
There are subtle sound differences you learn over time with the straight "beep" in discriminate mode. The VCO variations on the detectors that have them provide more information.
I like the rubber duck sound. Once I started to learn the duck's language it has lead me to better finds overall than my multi-toned target ID detectors. There are certain environments (wet salt water beaches) that I prefer my other brand detector; but on dry sand, fresh water, and land, it is kind of hard to beat the variations of the Tesoro quack once you learn it. They are light weight, very effective detectors.
Oh, and does reddirtfisher mean highly mineralized clay areas? If so, I'm thinking the Vaquero quack may be a good tool for you.
Merry Christmas!
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