Q: I have a 5.1.4 speaker system hooked up to a Marantz SR7010 AVR. My speakers consist of Yamaha NS-777 mains, NS-555 surrounds, NS-444 center, and NS-333s for the elevation channels. I want to upgrade the mains and the center speaker. Since all of the speakers in my system are rated at 6 ohms impedance, does that mean I have to upgrade to other 6 ohm speakers, or can I mix impedances?

- Steve Carlisle

A: The short answer to your question is that you absolutely can mix and match speakers of varying impedance. The Marantz SR7010 is capable of handling speakers with impedance ratings between 4 ohms and 16 ohms.

According to the SR7010 manual, there is a speaker impedance setting that needs to be adjusted if you use 4 ohm or 6 ohm speakers in the system. If you upgrade the front speakers to 8 ohm models, you’ll want to keep the setting at 6 ohms. However, if you upgrade to 4 ohm speakers, you’ll need to change the AVR’s impedance setting to 4 ohms.

It just so happens that I have a Marantz SR7010 in for review, and I already had a chance to mix-and-match speakers of varying impedances. Furthermore, I was able to successfully integrate speakers from various manufacturers into one cohesive-sounding surround system, thanks to the room correction EQ magic performed by Audyssey XT32.

In theory, you’d want to upgrade to speakers that match the timbre of your current surrounds and elevation channels. However, since you are replacing the front soundstage, presumably you are not interested in being bound by the legacy of your current speaker system. In my experience, this is not a big deal as long as you have sufficiently competent room correction software, and Audyssey XT32 is sophisticated enough to do the trick.

There is a wide world of speakers out there to choose from, and the SR7010 should be able to drive the vast majority of them to very satisfying levels. That said, one thing you can look into is buying speakers that feature higher sensitivity than your current ones do— 89 dB/W/m is a bit on the low side. It’ll make life easier for the AVR’s amps, and you’ll add some dynamic headroom to your system.

Now, having said all that, ideally you could look into upgrading your surrounds. I think you can get away with keeping NS-333s for the elevation channels, but I’m left wondering if you won’t gain considerably from using dedicated surrounds that are a match for whatever speakers you choose to replace your left, right, and center.

You don’t mention what you plan to do with your current NS-777 towers, but since the SR7010 offers 11-channel processing, one option you have is to add a 2-channel amp to your rig so that you can run a 7.1.4 Atmos and DTS:X-compatible speaker system. In such a system, you’d use the NS-777s as surrounds, and put the NS-555s to use as rear surrounds—the immersive effect of 7.1.4 is fantastic!

It’s also worth noting that the rated nominal impedance of any given speaker may not be an accurate reflection of how easy or difficult it is to drive. Impedance varies by frequency, and I’ve seen plenty of instances where speakers rated at 8 ohms dip down to 4 ohms. Nevertheless, I have not had any issues with the SR7010 while driving a variety of 6 ohm and 8 ohm tower speakers—it’s got plenty of power on tap.

I wish you the best of luck in your quest to upgrade your speakers. Your current outfit strikes me as being quite competent, as is. Therefore, I’m curious as to what you’ll choose for replacement speakers—let me know.

If you’ve got an AV question, please send it to Scott Wilkinson (scott@avsforum.com) or Mark Henninger (imagic, mark@avsforum.com ) via PM or email.