Is CYBP where all the en-route traffic is handled for this area of airspace.
No, they have remote transmitters located all over Alberta. If you live in the general vicinity of any of the following locations you should be able to hear the Edmonton ARTCC controllers on the following frequencies (and the general area the sector covers).
Calgary - 133.300 (low altitude, west of Calgary)
Brooks - 132.650 (low altitude SE of Calgary), 125.050 (high altitude, east of Calgary)
Edmonton - 132.775 (low altitude, east of Edmonton), 134.900 (high altitude, east of Edmonton)
Lethbridge - 132.750 (low altitude, south of Calgary), 135.750 (high altitude, south of Calgary)
Red Deer - 132.850 (low altitude, between Calgary and Edmonton), 135.125 (high altitude, west of Calgary)
Whitecourt - 135.600 (high altitude, west of Edmonton) , 132.050 (low altitude, NW of Edmonton)
Rocky Mountain House - 134.300 (low altitude, SW of Edmonton)
Delia - 124.450 (low altitude, east of Calgary)
Flatbush - 134.700 (low, altitude, north of Edmonton)
Lloydminster - 133.450 (low altitude, east of Edmonton)
Grand Prairie - 134.500 (low altitude)
Edmonton Center low altitude airspace extends up to FL280, high altitude airspace is FL290 and above.
It is common for them to combine sectors, this is where one controller will work mutiple frequencies and areas at the same time.
All Edmonton frequencies have cross-coupling capabilities, this means that if a controller is working more than one frequency the transmissions from the aircraft are rebroadcast on all the frequencies the controller is working. This allows pilots to hear the transmissions from other aircraft even though they are on a different frequency.
Same thing for someone monitoring on the ground, if you live near one of these locations and can hear the controller you can potentially hear aicraft transmitting on a different frequency hundreds of miles away. This is the case with the two frequencies on the Brooks LiveATC site (when it's working), as they are often linked together with other frequencies.