Reply To: call with 2 quintum without pbx or pstn 23rd August 2005 at 21:29 #29965 DUAL TalkGuest Daph, If you have an ISDN30 with all channels active, then you should be looking at the Quintum DX2030 MultiPath Switch to go between the ISDN30 and your PBX. Regards, Tom Howard, DUAL Talk, Internet Telephony Service Provider.