Cambridge Audio 840C

I found that at first the balanced outputs sounded much better.
But, I think the only reason they sounded better was because they were louder [more voltage output].
With the levels matched, the RCA's and the XLR outputs sound virtually the same, IMHO.

After 400+ hours of breakin, I've tried it both balanced and unbalanced (as well as a transport alone). I "think" balanced may have marginally better definition but I think Daltonlanny is right in that they are not matched levels so it's difficult to say. If you have a balanced rig, then by all means run it balanced, but I wouldn't hesitate to use the 840c via the RCA outs (or just as a transport).

I think there is now widespread agreement that to maximise the performance of your 840C, three things need to be done.

1. Run in for at least 200 hours
2. Replace the feet, which are a real weakness of the unit
3. Use the balanced connectors.

I've now clocked about 400 hours on this player and i enjoy it immensely. I bought the 840C after auditioning the Naim cd5i, Cyrus 6 & 8, Arcam CD192, Cayin CDT-17A and the MF A3.5CD.

I would like to comment on 2. & 3. above.

I've read many reports of 840C owners replacing the existing feet with Herbies Tenderfoot. This seems to have paid dividends - but also voids the warranty. I prefered instead to leave the feet in place but use another form of isolation. I experimented with a few options including Golden Sounds DH cones and pads. I achieved the best result with Nordost's Pulsar points.

On the RCA vs. XLR debate, unfortunately i can't make any conclusive comments because i used a different IC cable for both. Initially i used Nordost's Blue Heaven with RCA phono connectors. The result was most pleasing. But then the Nordost dealer threw me a Heimdall IC with XLR connectors to try. The dealer never got the Heimdall cable back - the difference in resolution and soundstage were given the short IC lenght (1m) staggering. XLR appears to be better in that it's higher gain (reducing the noise floor) but whether the overall difference was impacted more by the IC cable - i can't be sure, so the result in inconclusive.

Curious, what power cord are you running with your 840C?

I use a Nordost Visnhu power cord with my 840C.