[Harp-L] impedance transformers

["John F. Potts" <hvyj@xxxxxxx>]

Paul,

As a long time devotee of non-bullet style mics for harmonica, I have  
more than casual experience with XLR>1/4 inch impedance matching  
transformers. In my experience, the Radio Shack and Shure units each  
work fine, but both are much longer than a standard 1/4 inch plug as  
it protrudes from the input jack of your amp and are even more  
lengthy when the output of the XLR cord is connected to them. This  
creates leverage that will put significant pressure on the input jack  
if the cord is pulled or the transformer is bumped (as inevitably  
happens) which can damage the jack on the amp and/or bend the input  
plug on the transformer. Accordingly, it may be preferable he to use  
a "rat tail" transformer on which the XLR receptor is separated from  
the 1/4" jack with a short length of mic cord, so only the 1/4 inch  
plug protrudes from the jack on the amp. Peavey makes one and I am  
sure other manufacturers do as well. I also find that they are a  
little easier to handle and carry around.

Some say that there's differing quality among IMTs, but all of the  
impedance matching transformers i have ever used sound fine and about  
the same EXCEPT the rat tail transformer made by Audix. The one i  
tried produced a very weak signal that was significantly diminished  
in volume and tone. I don't know if the particular Audix transformer  
i tried was a defective unit or if they are all that way.

JP