Amstaff

OP - where are you located?

Where are you located? I have a Denon 4311Ci sitting in its box. I used it for several years and replaced it with a Yamaha RX-A3060 only because I wanted the newer features. The 4311 will not be short on power.

I would guess the 77" TV weight itself will not be an issue for an RC-64. However, do verify that the TV stand will fit correctly(completely) on the speaker. I have an 85" TV and the stand legs are wider apart than the width of a RC-64, so it would not work. Me thinks a 77" TV falling off the speaker will make for a bad day.

That is a reasonable TV and reasonable speakers. But that says nothing. What size room are you in? What AVR will you drive these with? What will you be listening to? TV/movies I assume? Are you going to get a subwoofer? Any surrounds - or strictly 3.0 or 3.1? Welcome to the forum....and the rabbit hole 🙂

That receiver should work fine. Your speakers can take 100W continuous, that receiver will put out less than 75W over 3 channels. That will still be plenty loud. You could go a bit bigger on the receiver, I would not go less.

I lined my RF7's up where they are toed in so the line from the center of each speaker would intersect about a foot or so behind the MLP - I did not over think it. Not sure anything else would make a noticeable difference. Not sure if what I did would make an noticeable diff to any other position. Try it and see. Good luck 🙂

What does your existing Onkyo not do for you? It seems like a robust receiver. If there are certain features your are lacking and want obviously look for those. The receivers look to be all reasonably similar in power output. The Marantz 7706 looks to be a pre-amp only. What amp would you use? Or, you may just want one, which is fine too 🙂

IMO this not a warranty issue. Return to the place you purchased them. Was that Klipsch directly? If the retailer does not want the return call your credit card company. Warranty is for when stuff goes bad after delivery.

Sounds like they already had a sub and replaced it - so, it "should" work....

Ok - so what I understand you already had a powered sub - right? The "Boss woofer". This was discretely powered - right? Where was this attached to your receiver? What is the Boss stuff you had? Car audio stuff? Plug the Klipsch s/w in the same port. Likely Pre Out SW Connect to the line in on the sub. Make sure the gain is all the way up (be gentle with the AVR volume). Try it. Make sure you have a bass heavy source (not a news channel etc). Adjust the gain to where u think it sounds ok. I have never had your setup - just saying something to try.

Yes. I have a Salamander Designs Synergy 345 - link below. This stand has space for my RC-7. My RC-7 measures 26"W, 9.1"H and 13.5"D. Your RC-64iii is 35.8W, 8"H and 15"D. The center speaker opening in my Synergy 345 is over 40" - so the RC64-iii will be a perfect fit. https://www.salamanderdesigns.com/av-cabinets/synergy-model-345/ There is a fair amount of customization that can be done when ordering. It comes unassembled and goes together like any other furniture you put together. I searched high and low for this back in 2009. I could not find anything to fit the height of the RC-7. IIRC the height of the opening is listed at 9". I had to remove the rubber feet on the center shelf to get the RC-7 in there. You won't have this issue. I have an 85" Sony TV on top too. They are not cheap, but good stuff is usually not.

I bought a Salamander Designs Synergy TV stand specifically to accommodate the center speaker (RC-7) in my case. If you need a shelf only. You may need to fabricate one yourself. And, ensure it is anchored to wall studs not the drywall (unless your walls are brick or concrete as they are in some parts of the world).

I had a similar issue with my older Denon AVR-4311Ci. It was relegated to the bedroom and I got a new bedroom TV (LG CX OLED). Both say ARC - not really compatible. Ended up the Denon ARC was "old" spec. I bought a new model (2020 or 21? Yamaha - RX-V4A) receiver and all works great. Not as powerful as the Denon - but it is the bedroom. Yes, ARC has some challenges especially with old vs new stuff. Optical worked fine on the Denon....but I wanted ARC functionality 🙂

28*8*8 is a big space. Do NOT get hung up on a Klipsch sub (Klipsch speakers are awesome, better subs to be had). I have a 18*12 room (9ft ceilings), open at back to the kitchen area. The SVS-PB16Ultra does awesome (replace a Klipsch RSW-15 worked well, but Klipsch reliability with their on-board powered subs has been questionable) ).No room is perfect. Not sure my SVS is "enough on paper" for my room - but to me it works just fine. You can always turn a sub's volume down. 🙂

I like the amp idea. You still need at least 9.2 channels in the AVR as the AVR will do all of the sound processing. You would send 5 pre-outs from the AVR to the amp for the LCR & 600Ms. AVRs with this many channels are typically are on the higher end of the power scale. Take a look at the AVRs on crutchfiled.com. Filter your selection by channels - 9.2 and 11.2. Price range starts around $1500 USD.