Eichman RCA's - what makes them so good?

DIN / RCA / XLR has nothing to do with sound quality. What counts much more is the material they are made of. AES Standard rates copper as Standard for Signal transfer ability (=100%), Silver for example is 106, gold is around 90 and everything else is much worse.
When the unit has very cheap RCA input plugs (brass with gold plating for example), they are in the area of 60, that means, they reduce any input signal by min. 40 % from what is possible. That is the real problem, not cable rolling (most have good connectors but here it is the same, it is not magic, it is knowledge).
The next interesting fact is, when there are two options, for example RCA and XLR, or RCA and DIN, which one has the better amplification stage?

Most manufacturers try to save money wherever it is possible, (nearly) no one uses real high quality RCA in- outputs (or silver wire inside)....the problem is not the manufacturer, the problem is the mark up for the following distributor chain. This kills normally every try to move on seriously for best possible reproduction (and these inputs are in the beginning of the amplification chain).
I changed all the RCA in-outputs from my Lamm Preamp/amps to the best available ones and the difference must be heard to believe ... but that was really expensive. Impossible to do for a manufacturer, it would kill his profit chance immediately.

I don't think much of the Eichmans; A cheap plastic plug, IMO. WBT Nextgens are better and Xhadows are the best for all metal plugs. There are a few reviews on the web that compare various plug brands. Worth checking out.

Also as mentioned, most component jacks are cheap brass with nickel/gold plate. If you are to experience the best performance, the jacks need to be upgraded.

AES Standard rates copper as Standard for Signal transfer ability (=100%), Silver for example is 106, gold is around 90 and everything else is much worse.
When the unit has very cheap RCA input plugs (brass with gold plating for example), they are in the area of 60, that means, they reduce any input signal by min. 40 % from what is possible.

You sure about that % reduction? What does 106 mean, then?

I don't think much of the Eichmans; A cheap plastic plug,

Eichmann plugs feel cheap but they claim their research concluded that high mass is an enemy of good sound in a connector. So they seem to be cheap plastic for a reason.

Syntax - i'm not sure I completely agree with your view of the effectiveness of RCA vs DIN or XLR, after all, the pins in the DIN plug I used are silver plated brass ( and who knows what materials are used in the socket in the amp) yet the DIN plug performed so much better than the Eichman Silver Bullet RCA's

Does the silver plating on the pins overcome the reduced conductivity of the brass? - don't know

I do agree that ensuring connectors with the very best materials should be used for optimum performance.

Since replacing the RCA jacks in the amp, as Sonic_genius recommends, is not something I choose to pursue at this time - for me, this will remain an enigma.

A very nice sounding enigma :-)

Sonic genius - at $140 for 4 - there is nothing cheap about this plastic :-)

Seriously though - have you tried the eichmans?
If yes - how did they compare to wbt and others you may have tried

Any feedback is appreciated - thanks

I do think Eichmann should find a material that is more robust than the "plastic" they have selected - I felt more confident soldering the smaller pins of the DIN socket - never felt there was a possibility of the pins falling out.

But they worked and were cheaper than many of the competition