Here's another vote for Soraa LED lamps. I have 5000K Par30L's (vivid, 60 deg, CRI=95; no longer made, unfortunately), and I love them to pieces. Best light I've ever had. They are aimed at a wall-hanging corkboard covered with white craft paper (the reddish beige of the cork throws off my color perception). The Soraa LEDs are dimmable and don't change color temperature at all as they are dimmed until just before they extinguish completely. With an LED compatible dimmer (Lowes.com) it was easy to adjust them to exactly the light intensity I prefer (EV 9 plus-minus a third across the entire board, top to bottom and left to right).
I'm glad I ditched my Solux lamps. I had four of them on a 120v rail, each with it's own transformer. As I eventually discovered, each additional lamp/transformer after the first one lowered the color temperature of all of them by 100K. I also had to use the green glass diffusers due to the inadequate beam spread, which knocked down the color temperature another 300K or so on each lamp. There was no easy control over light intensity without also changing the color temperature.
An alternative to LED or halogen is fluorescent, which is what I used after the Solux lamps and before I heard of Soraa LEDs. There may still be some are 5000k tubes out there. As with LEDs, if you have a CRI >= 90 they should work well enough. I only changed to the Soraa LEDs from fluorescent tubes because it was difficult to get even illumination across my wall-hanging corkboard with the fluorescent fixtures I had.
I prefer 5000K because color prints tuned under 5000K can be viewed under a wide range of color temperatures and still look reasonably good. For example, when I showed color prints tuned under my 3500K Solux lamps (which I eventually found were actually at about 2900K; see above) in a room lit predominantly by north blue skylight, all the warm colors in the prints just died. I still show prints in that location, but since I changed to 5000K illumination all the colors seem fine. Also, I have some monochrome prints that look completely neutral under ~3000K light, but are hideously green under 5000K or daylight. If you cannot dictate the color temperature of light that will be used to view your prints, I think a neutral color temperature is the way to go when it comes to an evaluation set up.
Mark G.