Inductance and gap...
Nah....
An Increase in air-gap will Reduce Inductance and increase the current at which the core saturates, it will also increase the low freq response to a higher figure--Great if you want to make a guitar output Tx.....
The reverse is true, but we are talking about gaps in the order of 0.1mm to 0.2mm Total gap--Meaning 0.05 to 0.1mm thickness 'paper' sheet as the spacer Mag field passes gap twice don't forget And it reduces the current at which the core saturates. If its a high grade core the core distortion appears rather suddenly as the point of saturation is reached ....
If your Tx is rated at say 50mA and your'e running at 35mA, Dont even think of messing with it--It is quite a precision item.--. Its just not worth the effort unless you have graded 'shims' below 0.05mm and some way of installing them to ensure all the laminations are 'butted' up correctly to the shims, and a Good Inductance measurement device to see what effect the alteration has made--Having made a few O/P Tx, I can say that 'setting the gap' is the very hardest part-- Especially when your'e needing a matched pair of Tx.........
Check out Yvesm Tx design proggie, Interesting to experiment with the gap, the coil winding/interleave numbers and core sizes and materials in there,-- Be easier to strike a new Tx from the data you can get using this great little proggie--Used it many times for various experiments/Tx design and chokes etc....
