What should I do

Condo or not, play it loud!

If you love Harbeths, I have a hard time believing you'll like the HD800, at least not without over-the-top warm tubes. Have you heard them? I heard them a while ago, and was not impressed (poor Qualia 010 ripoff). The HD650 or HD600 are both excellent, cheaper, and may be more along the lines of your Harbeth's sonics.

Also note that while Rogue tube amps are great, their built-in headphone jacks will not compare to a decent standalone headphone amp, or integrateds with a reputation for good headphone jacks.

You may want to look at a Manley 300b based preamp, which is also a state of the art headphone amplifier, it is one of the world's most remarkable preamps and I think you would find it to outperform the Gamut preamp, and then you can have your cake and eat it to, on some of the headphone forums this combination of preamp/headphone amp and the HD 800's has been lauded as one of the most synergistic and satisfying setups there are PM me for more details.

Mulveling's post really hits the nail on the head and I say this based on experience with equipment mentioned in post(s). I appreciate those who show respect for their neighbors rather than the common me me me behaviors that have become the norm in many places. Thank you for your civility which is becoming something of a rarity in so many areas of western life.

I am an ex-Harbeth owner myself and I would recommend you take a listen to the Grado GS-1000i phones. I basically consider myself a headphone hater and I much prefer listening to speakers in a real space. To me, whatever frequency-based or alleged sonic superiorities of other phones, IMO the Grados sound more like listening to my speakers and less like headphones. At the latest NY show, I listened to many different phones and, except for the Stax, I still preferred the Grados for that reason. Plus,they will sound absolutely wonderful with a Grado battery headphone amp for $350, which is a definite plus. You can always upgrade the headphone amp later if you feel the need.