I looked into FFmpeg & Lame, in relation to my FLAC music collection.
Using just FFmpeg as Step 1, this is the most simple downsampling syntax:
ffmpeg -i %s -b:a 192k -f mp3 -
And it works. Leave Step 2 empty.
It could be that my ears are tricking me, but it seems that transcoding to WAV with FFmpeg:
Step 1
ffmpeg -i %s -f wav -
&
Step 2
downsampling to 192 kbps MP3 with Lame:
lame -b 192 - -
gives a clearer - less distorted - sound.
You'll have to download the latest codecs:
http://ffmpeg.zeranoe.com/builds/
http://sourceforge.net/projects/lame/files/lame/3.99/
and copy ffmpeg.exe and lame.exe & lame_enc.dll to ....\subsonic\transcode
Let me know what you think.