with a cd you are familiar with... not an mp3 nor xm/siris radio but a high quality commercially recorded cd. Try both positions on the amplifier - MAKE SURE YOU TURN THE EQUIPMENT OFF BEFORE SWITCHING THE OUTPUT ON THE AMP.
In straight talk an 8 ohm speaker uses electricity more efficiently than a 4 ohm speaker. When you switch the amp from 8 to 4 ohm the amp is preparing to push more power to the less efficient speaker. Consequently you may hear more volume and detail out of your Canton speakers at the 4 ohm setting. Ultimately, it's up to you since the speaker says it can be run on a 8 ohm output. You may notice the amp running a bit warmer so make sure you have plenty of ventilation.
Many teens have blown their bedroom stereo by taking their car sub and putting it on their home equipment because the house stereo didn't have enough power to push a low impedance speaker at full volume. LOL
grim
I have a Yamaha RX-V657 receiver, which can be set for either 4 or 8 ohm impedance.
I just bought some Canton 130 speakers, which are rated "4 to 8 Ohm nominal impedance".
What setting should I use on the receiver?
(I got two different answers from the store where I bought the speakers, and the store where I bought the receiver, so I am confused.)

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