Polk Monitor 60 & CS1 question

[Rob J in WNY]

Nicky-D,

Congrats on the purchase. I'm sure you'll love the speakers.

I have Polk Audio T90e speakers for fronts. They are exactly the same as the Monitor 60 in every way, except that they are all-black. Basically, they are the "Euro" version of the Monitor 60. A few of us on the forums here have them.

According to Polk, you can actually run the Monitor 60 as "large" speakers - bypassing the crossover completely. I would suggest still running them as "small" and giving them a crossover setting of 80Hz, which is fairly standard. This will free up the burden of low-frequency reproduction from your receiver's amplifier. Set your CS1's crossover to 80Hz as well.

Those are pretty run-of-the-mill crossover suggestions, but they will work nicely for you. Of course, you can always run your Onkyo 705's Audyssey room correction setup and let it choose the crossover points for your new speakers as well.

The Polk Audio Monitor 60 and CS1 are both 8-ohm speakers. Although there are some notable exceptions, most in-home speaker systems will be rated at 8-ohms impedance. This rating is inherent to the speaker itself, and not the receiver. However, some receivers allow the user to set impedance ratings so that the receiver will operate nominally for different speaker impedances. Simply match the speaker impedance.

In your case, with a maximum of 6-ohms setting, I would say just choose the 6-ohm option, as this is the closest. That said, running speakers of higher impedance than an amplifer nominally operates is safer than the opposite - running speakers of lower impedance than an amplifer is rated for.

If you are mixing 4- and 8-ohm speakers (many HTIB speakers are 4-ohm) in a multichannel setup, know right off the bat that this is not recommended. If you must, then I would suggest setting your receiver to the 4-ohm option. This way, you are doing the best to safeguard your receiver. Without getting into the electrical theory of it all, just keep in mind that lower speakers' ohm rating is, the closer they are to a "dead short," electrically speaking. Speakers with 4-ohm ratings make it difficult for amplifiers not rated to handle such low impedances to remain stable during loudly played program material. This can cause amplifier overheating and damage.