Disclaimer: My Naim CD5 is currently for sale as we are in the midst of six month renovation of our house so I've disassembled the second system and am selling to pay some bill$.
I can't speak about the Arcam as I've never heard it, but I have owned the Naim for a year in my second system and love it. I'd say you are right on in characterizing the sound as a bit on the softer side, though I wouldn't call it a 'warm' sound. It is most certainly very revealing. Built like a tank. Has a musical "rightness" to it, for lack of a better word. The High-Cap does improve the detail and low-end in my system. If you do get a Naim player, make sure it is a current model or has the PIC upgrade that allows it to play copyright protected CD's. Upgrading an older player costs $75 for the kit which can be ordered from any Naim dealer and is a plug-and-play as easily installed as a computer memory chip. Ad another hours (half hour if they charge actual time) labor at the shop if you are not comfortable doing that.
Nitpicking complaints about the Naim: Minimal information in the display. Magnetic puck takes a bit of getting used to and is a bit of a pain sometimes. DIN connector means you have to get your favorite cables adapted to the connection...either that or try some of the higher end Chord cables that are made for that connection. Naim USA will convert the output to RCA's but I'm not sure what the cost is.
Overall, the virtues far outweigh the nitpicking so I'd highly recommend the player.
Another player/DAC series I'd consider in your price range is Muse.
Marco
I can't speak about the Arcam as I've never heard it, but I have owned the Naim for a year in my second system and love it. I'd say you are right on in characterizing the sound as a bit on the softer side, though I wouldn't call it a 'warm' sound. It is most certainly very revealing. Built like a tank. Has a musical "rightness" to it, for lack of a better word. The High-Cap does improve the detail and low-end in my system. If you do get a Naim player, make sure it is a current model or has the PIC upgrade that allows it to play copyright protected CD's. Upgrading an older player costs $75 for the kit which can be ordered from any Naim dealer and is a plug-and-play as easily installed as a computer memory chip. Ad another hours (half hour if they charge actual time) labor at the shop if you are not comfortable doing that.
Nitpicking complaints about the Naim: Minimal information in the display. Magnetic puck takes a bit of getting used to and is a bit of a pain sometimes. DIN connector means you have to get your favorite cables adapted to the connection...either that or try some of the higher end Chord cables that are made for that connection. Naim USA will convert the output to RCA's but I'm not sure what the cost is.
Overall, the virtues far outweigh the nitpicking so I'd highly recommend the player.
Another player/DAC series I'd consider in your price range is Muse.
Marco