Transformer-isolation for inputs/Bronx Cheer?

[Rodgre]

Over the weekend I built up Tim E's Bronx Cheer which uses a transformer on the input. I admit that I don't really understand it's effect on the circuit, but it got me thinking about uses for transformers in other circuits, and I wondered if it would be beneficial at all to use an isolation transformer at the input of circuits which are effected negatively by incorrect impedance.

Thoughts? Have I already missed this discussion?

Roger

[petemoore]

  Works.
  More trouble than an input cap, takes more board space, tends to be expensive.
  Easy way to lift a ground !
  I wouldn't mind having some really nice 1:1 audio transformers for building a pre-amp.

[earthtonesaudio]

In this circuit the inductor is not used for isolation, but as a filter element. 

What it does is shape the frequency response to mimic a guitar pickup's response.  Like it says, if you connect a passive guitar pickup directly, it's not needed, since the guitar pickup is the inductor.
Check out the AMZ pickup simulator for more info.
http://www.muzique.com/lab/pickups.htm