I just took my first plunge of buying new strings for my NS Cleveland ply. After much consternation over some non-universal opinions (Huh? You mean everyone doesn't agree on everything??), I just decided that Obligatos would be a good place to start. If Spirocores, which I was used to almost exclusively, are the extreme opposite to guts, I figured these would at least get me some of the way toward the "other" sound and bow better too.
These totally do it for me. If the Cleveland wasn't already a cannon, it sure is now! Tons of bottom end.
The G & D are a little more gut-like and have an attack that is instantly more real and natural sounding to the way I think a bass should sound. The metallic tone and upper harmonics, which I didn't fully realize how much the Spiros were producing, are vastly reduced too, resulting in a darker, more organic tone. There is somewhat less sustain than the Spiros, but there's still plenty, which I generally like.
The A & E have every bit as much sustain and growl as Spiros, at least while the strings are so new, also good w/ me, and too comes with reduced metallic tone, as with the other two strings. Very punchy with a lot of air.
The lower tension, which I didn't think would be that noticeable according to the tension chart on TB, made my bass much easier to play. I no longer want to reduce my string height. It's about just right.
The only drawbacks are getting the strings stretched out so they stay in tune, and there's a little bit of roll to the strings under the fingers, that while being somewhat objectionable is not really much of a hindrance. And the expected lifetime I know won't be "forever," like Spiros. At this point, I would gladly replace these once a year to keep this sound.
At a practice everyone in my band heard the difference and complimented me on the tone. I didn't use an amp, which I sometimes do, and no one missed any volume. With the tone and the reduced tension, I was in heaven. I had not experienced this sensation since I first played an NS Cleveland! This truly was the biggest leap in gear since getting this bass and I honestly feel these strings have already made me a better player.
Jim Henderson said:
...Mike Childree suggested Obligatos for the bluegrass sound. Having heard Big Mike's cuts on TB, I respect his opinion, Additionally, a fellow bassist had a 40 Kay with the obligatos on it and Mike was right. The only solution was to buy a 52 Kay that was for sale at the festival and install obligatos...
Both these guys are right, though I don't think this advice is at all limited to bluegrass music.
Oh yeah, they're a little easier to bow and my wife noticed the arco tone was better, but I guess me and the bow still need some work there!
Final disclaimer: Since I've not tried many others, perhaps a lot of other strings are as good or better on similar basses, and maybe I'm not at the end of my journey. But I'm still surprised at the improvement and don't, just now, feel I need to continue the string journey.