Converting floating ground audio to common ground audio

I want to run a 4 wire stereo output (left+, left-, right+, right-) into a common ground audio device (left, right, ground). I have done this successfully with a pair of small audio transformers but these are larger than I'd like. I was wondering if there was a simple way to do this with a few small components. I would prefer to keep attenuation to a minimum.

Thanks alot

JeffM

Use low noise audio preamp. IC with symmetrical input.(differential)