I ordered the strings Wednesday, they were shipped FedEx Thursday, and arrived today. One set of steels and one set of nickels. As promised, I compared fresh sets of nickels: black versus blue. Here's my test platform: Sadowsky P5, Carvin B800, Sadowsky SA410. The rack gear in the middle was not used.
First step: install a fresh set of the black labels. This is the sound I've grown accustomed to since my Elixirs finally died two months ago. I dial in a happy sound on my bass rig and jam away for awhile once the strings have settled into tune, so my ears get accustomed the the fresh set.
Then, I look at the blue labels. Interestingly, the packages are smaller than the black labels. The strings are coiled a lot tighter. Just an observation... I don't think it's relevant in any way.
The next step is of course to install the blue label Bright Nickels. I pause for a moment, wishing there was a way to compare them side to side without having to swap string sets back and forth. A candle lit up in my pointy little head... there sure is: string the bass with alternating blacks and blues. So I did: I switched the B string, noodled for awhile, then did the same with the A and finally the G. I left the bass strung like this for awhile:
I figured that this way I could compare timbres without having to rely on memory. It's not a perfect A/B, but it turned out to be quite useful. Eventually I switched the bass over to all blues.
My thoughts: both sets were smoothly wound. I didn't notice a difference in tension, but I wasn't looking for one. I did notice a difference in tone. The black label nickels were more airy on top. The treble on the blue label strings was voiced lower, and overall they had more of a bell-like chime to them... almost reminiscent of steels.
My hunch is that I'll like the blues better, but it's hard to know after a relatively quiet home test. Also, I have to mention that both sets were brand spankin' new: I don't know how the blues will sound when they settle in, nor do I know how long they'll going to last under gig conditions. I am looking forward to using the blue nickels at tomorrow night's gig through my NV610!