whats the differance between rti a7's and tsx 550t?

Couple of big differences... The midrange on the 550t is two 5.25" woofers while the A7 is a single 6.5". This might address some of the complaints of a "weak" midrange that people complained about with the A7's. The other major difference is that the 550t bass drivers are slightly larger (8" vs 7") but the 550t bass drivers are passive and not active like the A7's. This should make them far easier to drive with modest equipment than the A7's. These are the major things that jump right out at me. As usual the best thing to do is to try and get your ears on both and see what you like best.

A reviewer says the 125 watts my receiver puts out isn't enough for these speakers. Tech details says between 20 - 300 watts will work. Which is rite?

Tech is right I have a yamaha rx-v677 that's rated at 120 watts per channel and its more than enough just make sure your thd is .09% or below. These speakers are power hungry so I had to manually adjust my speaker levels but they sound amazing! My wife event commented on how good they sound and she is so not interested in my home audio gear

Can any one explain why there are four wire terminals? See the picture on the top left. Thanks

You reply/answer sounds about right to me, to the tee!! I was thinking of Bi-Amping for a long while now, but I really don't think it will improve anything, when my Receiver is rated at 140 watts per channel and my two Subs are handling most of the down low bass frequencies below about 80Htz!!! I think I will not waste yet maybe another 2 Grand for a power amp! Well, I certainly don't know as much a your detailed and lengthy answer (thank you for taking the time to help others) conveys, but maybe I'm just imagining that my Polk RTiA7 sound more ALIVE with clearer/articulate/slightly brighter in the mids and highs frequency range, but because I had some extra #12 Monster Cable left over after wiring my Yamaha RX-A3030, Polk 9.2 Surround System, I said why not, and "Bi-Wired" the two front RTiA7 Towers. I instantly smiled when I first did this after listening to my Polk Towers for a few weeks already. I never bothered to try them with just the one cable and jumpers in place again, but man I swear that initial sound put a smile on my face. I also have two SVS PB12 Subs, and I have my Towers set for 80Htz on the Receiver/and I have the Towers set to SMALL on the receiver with the rest of my Polk compliment of matching Center, and all the different surrounds and effects speakers. I hope I set those Towers to the correct size LARGE on the Receiver!!! I now may go back and do a listen with them on Small and see if they sound even better!!! Thanks again for you detailed reply!

What would be an ideal receiver for these spaekers?

I have a Harman Kardon AVR 135 that's exactly what it is REO video receiver and it pounds it pounds I think it's I think it's 60 watt 2 Channel but it's 7.1 DTS all the goodies you know all the fields Optical HDMI hookup you know I mean this stuff is so easy these days you know how you hook to hang up optically with HDI as well I realize HDMI supports audio to but I default to Optical way better you get the true bitstream when you're listening to a DTS application but that red DTS light doesn't light up you're not getting DTS you're getting enhanced prologic crap hope that helps you don't need a ton of wax but get a good receiver I mean I like Harman Kardon Gannon Yamaha you know I'm an old-school guy I mean I was in Pioneer guy with a knob as big as a softball you know analog dude tubes Ted Nugent Van Halen crap like that dig it cool make a drink have some more turkey the bartender

Is Waterproof	FALSE
Color	Cherry
Subwoofer Diameter	7 Inches
Speaker Type	Floor Standing
Controller Type	Corded Electric
Speaker Size	6.5 Inches
Audio Output Mode	Surround
Antenna Location	construction
Mount Type	Floor Mount
Speaker Maximum Output Power	300 Watts
Compatible with Vehicle Type	Car
Item Weight	60 Pounds
Number of Audio Channels	1.0
Frequency Response	27000 Hz
Impedance	8 Ohm
Power Source	Corded Electric

Polk Audio RTI A7 Floorstanding Speaker (Single, Cherry)

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