my 787 has no switch to go from 4 to 80ohm so no go there also it states the 787 is rated at 6 ohm.I have used other 4 ohm speakers with this receiver with no problems at all.what are some good 4 ohm load receivers that are comparable with the onkyo 787?and why is this a lower end receiver? same amp and power supply as the 797.who knows maybe Onkyo makes junk.as far as kef speakers go they may have a 4 ohm rateing but it's a diffrent speaker all together so you can't compare