i cannot, under *any* circumstances agree with gregadd on this one.
all the tube buffer does is further distort the output signal, by design!
if you like the sound of tubes, get a player with a tube output stage or mod your player to have tubes in the output stage. don't run the signal through SECOND output stage just to add the "tubey" sound to it. all you're doing is altering the signal by running it through more pathways.
remember: if adding something into the audio chain (other than maybe an upsampler, which at least has some theoretical benefit) alters the sound audibly, it is degrading the signal. period. the tube buffer cannot improve the signal it gets. it's like adding a pouch of dirt to the spout of your kitchen spigot - you may like the taste of the water that comes out of it - but don't say it's as pure as it was before it got there.
all the tube buffer does is further distort the output signal, by design!
if you like the sound of tubes, get a player with a tube output stage or mod your player to have tubes in the output stage. don't run the signal through SECOND output stage just to add the "tubey" sound to it. all you're doing is altering the signal by running it through more pathways.
remember: if adding something into the audio chain (other than maybe an upsampler, which at least has some theoretical benefit) alters the sound audibly, it is degrading the signal. period. the tube buffer cannot improve the signal it gets. it's like adding a pouch of dirt to the spout of your kitchen spigot - you may like the taste of the water that comes out of it - but don't say it's as pure as it was before it got there.