Another good use for a tube buffer is between a tube preamp ( relatively high output impedance) and a solid state amp with relative low input impedance. I use a fully balanced tube buffer between the second set of XLR outs on a ARC ref3 with 600 ohm output impedance and a pair of JL Audio subwoofers with 10k input impedance. Without the buffer the combination of the subs + my main amplifier ( 20k input impedance) weigh down my preamp. I use an Audio Horizons 5.0n tube buffer with upgraded tubes and it improves the sound in this application. - Jim
