I've seen a few comments already on the comparison between these two circles. Foreground Eclipse is definitely more well known compared to 回路-kairo-, with the latter usually tauted as being an alternative for those who have been listening to FE.
But are they that similar as some would indicate? A quick listening would provide some basis for the suggestion:
So kairo is FE with less scream and a more sultry female vocal? Well, almost - but not quite. I used to joke that 回路-kairo- is like Foreground Eclipse, with less screaming, more mature sounding lead female voice, and a frontwoman with thick makeup... but, enough with that tongue-in-cheek remark.
On the surface, both circles seems somewhat familia enough. They're assigned under the wide umbrella of Touhou Metal/Rock arrangements, with lead (clean) female voice and accompanying male screaming. They are active in attending gigs here and there. They can be both aggressive and mellow when they feel like it. And they have their share of members leaving (in both case it's the guitarist, interestingly enough...)
But that is pretty much where the similarity ends. For one thing, their sound are actually very much different: Foreground Eclipse is more what you'd call heavy metal and metalcore, whereas kairo is more a combination of hard rock, ambient, and post-rock. The screaming on FE is also more abundant - and form the core of the circle - whereas for kairo the screams can be thrown in at unexpected places.
What I meant by the last point is that FE would usually announce the arrival of their screaming clearly:
Whereas kairo, on the other hand...
Bet you didn't see that screaming coming
That screaming around the starting that you might miss it
Lyrically (and somewhat sonically) both circles do seem to be heading more towards what you'd be calling 'emo-ish'. That much is obvious, seeing the list of favourite bands of FE and their self-designation of Emo for the genre of kairo's music. Lyrically both Merami (FE) and 556t (kairo) seems to have a penchant for writing sad and emotive lyrics, but I'd say that Merami can be more aggressive (the accompanying music further enchance this) while 556t seems to drift more towards slower and mellower singing.
'The broken hand of this clock/Won’t reach you anymore/My chest feels like it’s about to burst open/So I cry.'
'Kill me/Only when I have died could I know/How I never needed/Such beautiful wings'.
And here are some of their original works, to really highlight that they can be mellow when they want to:
So is 回路-kairo- really an alternative to Foreground Eclipse as some would have suggested? If you fancy some post-rock and ambient sound after going through the heavy parts off FE, then they are a real good alternative. I wouldn't really refer to them as an alternative, personally - as I felt that they are actually very distinct from each other. They are both up there in my list of favourite circles to listen to though.
Unfortunately as some might have known, Foreground Eclipse have recently announced their disbandment, which really sadden me as I really love their work. 回路-kairo is one of my favourite circle to listen to (up there with the list of Buta Otome, CROW'SCLAW, Demetori), and while they are still going strong, they have been going through some interesting evolution throughout their work.
In future writings I'll be focusing on the two circles in much more details, going through their released works so far.