[Elecraft] 4-ohm to 8-ohm question

[Jim Brown]

On Mon,5/2/2016 1:15 PM, Eddy Avila wrote:
> My K2 audio output is 4-ohms which I drive into an 8-ohm ICOM speaker with filters. Yes, it works OK, but I would like to match them better.

There is no need to do that. Audio output stages are constant voltage 
sources -- that means they have a VERY low output impedance, typically a 
fraction of an Ohm. The impedance rating of a loudspeaker output stage 
is the MINIMUM impedance that the stage can drive safely. Any higher Z 
will work fine. A transformer would do three things 1) increase the 
headroom (max loudness) by about 2.5 dB (there's loss in the xfmr); 2) 
increase distortion at low audio frequencies (because most audio xfmrs 
aren't very good; and 3) deplete your bank account.

73, Jim K9YC