Very large room HT

First you need an amp or pre-amp which has the possibility to use Audyssey Pro. Second you need to buy a kit ( 700 dollar). And 3th you need to buy a key ( 150 dollar) to get access in your amp. It is not an easy system to use. Because you have to work extreemly presize or it will work against you. The microphone stand as Audyssey delivers for Pro is useless. They way Audyssey measures the results are ok. I measure at totally different places and hights. And I do my own changements in the settings. This gives a superior result compared to the Audyssey way. I did many tests during 3 years with Audyssey. And now almost 1 year with Pro. I get a lot more dynamics and resolution at how I use it. I even can create a wider and deeper stage. And the whole freq. respons I can adapt how a client wants his personal sound. I have a better timing and even more drive than what I had with the XP-20 which I owned for 2 years. The separation is even better compared to the XP-20. And the articulation of voices is more open compared to the XP-20. I can crush every pre-amp till 10.000 dollar with ease. In every aspect I can give a higher level. Even in natural sound. Last week I sold a 5509 with Pro also to a customer with a Pass Labs Pre-amp. So even at 2 channel I get a higher level. For Multi-chanel it is even more simple to win. You cannot use Denon with Pro for it. Why? Because it is a 2-dimensional brand. Wenn you connect it to a Pass Labs the wide and deep stage is gone. A few weeks ago I sold my old audio rack to a person who thought Denon was the best in Surround. He ownes the Denon AVP-A1HD. After hearing my set his word were: so this is the end of Denon for me. He understood that Denon is a 2-dimensional brand. And now he also wants a 3-dimensional image. It is that easy to convince. Only Onkyo and Integra can create a wide and deep stage in there price tag with roomcorrection. Primare can do the same but lacks roomcorrection. The Sp32 is inferior to a 5509 with Pro in every aspect. This year I sold 2 5509 to SP-32 clients.

is THE 5509 OVERKILL FOR 5.1 HT?
and WHICH AMP COMPLIMENTS IT BEST?

depends how much money you have? Always go for an amp which can make a deep and wide stage. Or you go back to standard audio= 2-dimensional audio. It is that simple! In the world of audio most amps are in the 2-dimensional league. Even many highend amps will give a worse deep and wide image. That is why I do not sell 2-dimensional audio anymore. People who buy it do not understand audio or like to limit themselves I guess.

Per Bo...
"It is that simple! In the world of audio most amps are in the 2-dimensional league."
"That is why I do not sell 2-dimensional audio anymore."

There you have it Salmoni. All you gotta do is look for the specification in the manufacturers brochure that says dimensionality and stay away from those that are rated as 2 Dimension. Just choose an amp that is rated as 3 Dimension or even Multi-Dimension and you'll be OK. I believe you'll find this spec right under the spec that gives the amount of magic pixie dust sprinkled on the circuit boards expressed in milligrams.

hahahahaha.....there is no manufacturer who will tell you this. In the better shops were the sell good highend they know. It is something you have to find out yourself. Compare it and you will learn and understand what depth means. And wenn everything plays loose from eachother how much more fun listening will be. Take your time.