I just had my 1900 and MQ101 serviced and cleaned. Got them back and hooked up the 1900 without the MQ101 equalizer. Forgot that the preamp and amp had to be relinked in back of the 1900. Then I could not find the links for a long time. Looked high and low. Meanwhile I linked the preamp and amp with a hi-tech patch cord set RCA plug to RCA plug.

Question - which is better, link with patch cord or the exposed U shape wire links that I finally found.

Technically there's not a "better", only different. You would have to compare cables vs. links to ascertain if there's any sonic difference and if that difference is an improvement or not.

Skipping the contentious debate of whether cables affect sound hearing a difference will depend on how neutral the interconnects are. A dead neutral cable vs. links may yield negligible results, a heavily flavored cable like Cardas Golden Cross will affect the sound but whether or not it's an improvement will have varied opinions.

If you use the links I would recommend cleaning them. If they're gold plated a wipe with a microfiber cloth should be sufficient. If they're cadmium or otherwise dull looking a quick cleaning with DeOxit or something similar will assure ideal contact.

I used the fat cables for a while. They have gold ends and are the hi-tech kind. Later I re-hooked up the MQ101 equalizer with the same kind of cables. Put on a Chopin disc in the Rotel. That set with ML1 speakers sounds Soooo good. All cables are hi-tech, Rotel to tape mon, out and back to equalizer, and speaker lines.

David O'Brien, the gentleman here helped me set up my system in the 70s >>>http://www.roger-russell.com/clinics.htm