As a Dyn C1 owner I originally started with a Bryston B100 (100w @ 8ohm - 180w @ 4ohm). Later I upgraded to an Octave V70SE tube integrated (70w @ 4ohm) and all I can say the Octave bettered the Bryston by a lot in every way. The Octave V40SE (40w @ 4ohm) was enough to drive the C1's too. Also I have never heard of the Chi-F1 until this post so I can't comment on it.
That being said when you listened to the C1's did you listen to the originals or the newer MKII/Signature? I ask because I have since upgraded to the Signatures and they are better sounding at lower listening levels. They seem to be easier to drive. The only thing is the originals may (relying on memory) get louder but the originals need to be louder to sound their best. So if you listen to music quite loud most of the time the originals may be preferred.
That being said when you listened to the C1's did you listen to the originals or the newer MKII/Signature? I ask because I have since upgraded to the Signatures and they are better sounding at lower listening levels. They seem to be easier to drive. The only thing is the originals may (relying on memory) get louder but the originals need to be louder to sound their best. So if you listen to music quite loud most of the time the originals may be preferred.