I have my own reasons for doing so...
and that might not have any benefit to you at all
it's never a pain to try and answer questions...unless I don't know the answer
I'm not a real technical feller'

...and if I don't know the answer...I'll tell ya'.
I'm kind of a basic "meat and taters" type of guy....and I try to keep my responses simple and easy to understand.
I run my SE very hot with the gain jacked. Because of this I get some falsing and chirping at some sites. By running my sensitivity in semi auto...the SE really settles down for me and will still hit deep coins.
With too much falsing and chirping...it's hard to concentrate on deep silver hits which can sound the same on the initial hit.
Semi auto just stabilizes my SE and allows me to run the high gain setting I do...it just keeps the falsing and chirping to a minimum.
In the field...and over 100's and 100's of targets...I have yet to hit a deep coin in manual that I couldn't hear in semi auto.
There have been some cases where the sound I hear is better over the deep target in manual than when in semi auto....but I can still tell it's a coin.
Many times I will play with settings over deep coins...switching from semi to manual to see what I hear.
If I was in manual when I went over said deep coin...I might not have heard it anyway if the SE was falsing and chirping...so I stick with semi auto.
Now if I happen to stumble on an iron free site...clean ground...etc....I will put the SE in manual sensitivity...and Rock & Roll...but about 90% of the time...I'm in semi auto.
Take care...and if you have any more questions...please let me know. If they are technical questions though that require a scientific answer...please peck on someone elses' door.
