americanaudiophile :
You can use any speaker that has a nominal impedance of 8 ohms. 6 ohms would be OK but actually have less power available to them. You cannot use speakers less than 6 ohms. The speaker will have a recommended range of power so anything that has a max or about 165 watts would be OK. If your room is large and you want high volume then a speakers with a greater efficiency rating would be good. This is usually give as a volume at 1m in front of the speaker with 1 watt applied such as 89db at 1 watt at 1m. The higher the number the louder it will play at 1 watt.
Take some of you own music with you to an audio store and use you ears to determine what you like.
Better stores will be able to steer you to speakers that will work well with your receiver.
Thank you so much for helping. I am still confused because I am reading different specs. on the DN1040 receiver. The operating manual-USA model only: with 6 Ohm loads, both channels driven, from 20-20,000Hz, rated 100 watts per channel MINIMUM RMS power, with no more than 0.09% THD from 250 Milliwatts to rated output. Amplifier selection USA and Canada Min RMS output power (6 Ohms, 100 W + 100W) Stereo 6 Ohms 120W+120W) Surround Mode 6 Ohm 165W per channel.
THE MANUAL READS: Models of area code U2 only with 8 Ohms both channel driven , 20Hz-20,000Hz rated 100 watts per channel MINIMUM RMS power. Amp Selection( code U2 Minimum RMS out power 8 Ohms 20 Hz-20kHZ, 100 W+100 W), ( Stereo 8 Ohms 110W+110W) SURROUND SOUND output power to the second power? 8 Ohms 150 WATTS per CHANNEL
(Models of area code CA2) Which Area Code am I? UTAH, SO the online manual is different than the user manual.
I thought the lower the Ohms the better because of the resistance to electricity is lower. I understand the sensitivity of the speaker, 91 dB requires 25 watts to produce a given volume, the lower the dB the more power it takes to produce the same volume. I can not find NOMINAL IMPEDANCE, 6 Ohms have less power going to them because their is less resistance to electricity. Is their anyone I can TALK too? SONY replied...
SONY TECH SENT THIS...Re: Best 5 speakers for DN-1040
Go with 6 Ohms. All speakers should have the same impedance (refer to page 127 of the manual).