Cambridge Audio 840C

I've at least read through most of these posts and I'm surprised that there was not more mention of using the 840C's balanced outputs. As you probably know, Robert Harley in TAS made it clear that the 840C's sound is improved in all areas via its balanced outputs. I contacted him asking him to be a bit more specific about the differences, but his response was not very direct in this regard. This is what troubled me when I read the TAS review because I couldn't be sure how much better it sounded via its balanced outputs. I'm hoping to look into this more, but I'm wodering if some of those who aren't overly impressed with the 840C may have not listened to it in balanced mode. Harley felt it was important that it be heard using a fully balanced system. Unfortunately, many of us aren't able to do that.

If anyone has done the comparison of balanced vs. unbalanced operation of the 840C I would appreciate your input. It would be interesting to know if it really kicks its sound up a notch.

I did a brief comparison between my unbalanced and my balanced cables, but I suppose it's a bit of an unfair one as it was during the first 200 hours when things were breaking in. I started with balanced cables that were well broken in, and then my balanced cables arrived that I'd ordered specifically for the "improved sound" that RH discussed. I let these run for some time before really taking any time to listen again. There was improved openness and definition and imaging, but was that all due to the balanced cables being used, or due to the increased break in time, or both? Who knows. It sounds open, clear, articulate, and engaging, so I'm happy. I guess I could go back and insert the RCA cables now and see if I notice a reduction in any virtues from the player, sometime...
Also, I don't know if I remember anyone mentioning above, during the headphone discussion, the fact that the CD players that have a headphone output have a separate circuit for amplifying this signal for your headphones. So, when you listen through the headphone output, you're listening through a completely different amplification circuit, than would send a signal to your amplifier.

Rolloff

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.