Tube Buffer between cdp & pre



Are any of you using a tube buffer between your cd player and your preamp? If so,what improvements did you experience?

Thanks
moonguy
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My digital source Blacknote DSS 30 has a built in passive volume output, so to better match the impedances I use an Audio Horizons TB 5.0 tube buffer in between the Blacknote and my amp (W4S ICE amp). Without it the highs are somewhat reduced and it doesn't sound as good.
I have a MF tube buffer inserted between a tuner and Sony es receiver( not using internal tuner as it is very poor).I think it improves the sound considerably, with smother, less harsh highs I would like to try it for CD's without loosing the tuner. Can I use tape in/out on the receiver, and exactly how?