Thank you carlsbad2 and tksteingraber for not being alarmists. I purchased the titanium rod when I bought my copper rod from McMaster-Carr, both for under $20 shipped and only another $30 for the machine shop to cut them down to 20mm lengths. This has been, by a huge margin, the biggest bang-for-the-buck audio improvement I've ever made.
It had been a while since I'd had the copper slugs in the system since the silver and titaniums are much more suited to my listening preference, so I just spent a couple hours going back and forth with either in my Bel Canto DAC 2.8. I presently have a titanium in the Bel Canto CDT-3 transport and a silver in the Red Dragon S-500. I would have swapped these around to, but both are in the back of the components and take a bit of digging to remove the fuse tray so my apologies for only swapping out the DAC slugs.
As would be expected, the copper has a warmer or fuller sound. This does come at the expense of inner detail but does smooth out some occasional brightness. Where I particularly notice the loss of inner detail is in decays as the copper sounds positively truncated in this regard. The silver is more open on top and there is a greater sense of the area around the instruments. The copper sounds a bit dumbed down. The copper also throws slightly but noticeably larger images while the silver has more precisely drawn and palpable images. If you like warm and fuzzy, then the copper is your slug but for me, there is no comparison, and I just can't have the coppers in knowing how much better it would sound with silver or titanium in there instead.
