ZNY CTLR DESCRIBED POTENTIAL SEPARATION LOSS AT 12000 FT BTWN 2 ACFT BECAUSE OF SIMULTANEOUS USE OF MULTIPLE FREQS.

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WHEN THE FAA BOUGHT OUR COM SYS; THE VOICE SWITCHING AND COM SYS (VSCS) A FEATURE ADVERTISED BY THE VENDOR WOULD PERMIT DISCRETE FREQS TO BE 'LINKED' TO ALLOW ACFT ON ONE FREQ TO HEAR THE XMISSIONS ON ANOTHER AND AVOID BLOCKING OR GARBLING. I DON'T KNOW IF ANY OF THE ENRTE CTRS IN THE WESTERN UNITED STATES THAT HAVE LARGE SECTORS REQUIRING MULTIPLE FREQS HAVE THIS FEATURE. NY ARTCC DOES NOT HAVE THIS FEATURE. NORMAL OPS AT ZNY SECTOR 91 REQUIRE THE CTLR TO MONITOR 123.62; 124.9 AND 134.8 ENRTE SECTOR FREQS; 118.55 CLRNC DELIVERY FREQ AT UNV AND 121.5/243.0 EMER FREQS. COMMUNICATING ON THIS MANY FREQS OFTEN PRESENTS A PROB AS ACFT ON ONE FREQ CANNOT HEAR ACFT ON A DIFFERENT FREQ. THIS OFTEN RESULTS IN GARBLED XMISSIONS AND POSES A THREAT OF MISCOM THAT COULD RESULT IN AN ACCIDENT. ADDITIONALLY; WHEN SECTORS COMBINE; THE NEW FREQS COME WITH THEM. ON THIS PARTICULAR EVENING; SECTOR 92 HAD COMBINED WITH SECTOR 91 AND 124.62 WAS NOW ALSO IN OP. TFC LEVEL WAS MODERATE TO HVY WITH ACFT OPERATING ON ALL FREQS EXCEPT 123.62. ACFT #1 WAS ENRTE FROM PHL TO UNV AT 12000 FT ON 124.62. ACFT #2 WAS ENRTE FROM PIT TO AVP AT 17000 FT. AS ACFT #2 NEARED AVF I DSNDED HIM TO 9000 FT. THE READBACK WAS INITIALLY GARBLED WITH MULTIPLE ACFT TALKING. I DECIPHERED BOTH ACFT #2; READING BACK HIS DSCNT CLRNC AND ANOTHER ACFT CALLING FOR CLRNC ON 118.55. I FELT THAT THERE WAS POSSIBLY A THIRD ACFT INVOLVED AS WELL; BUT COULDN'T IDENT IT. SHORTLY THEREAFTER; BOTH ACR #1 AND ACR #2 WERE OBSERVED DSNDING. THANKFULLY; THERE WAS NO TFC BELOW ACR #1 OR SEPARATION ERROR WOULD HAVE OCCURRED. THE SIMILARITY OF THESE 2 CALL SIGNS CONTRIBUTED TO THE MISCOM.