Yes, but it will impress my friends and look cool!
(I'm seriously only joking). I suspect you are right. And replacing the receiver sometime down the road as the tech continues to evolve and mature will be less of a concern if I paid less for the the AVR to start. Do you think there is any particular advantage to going with a 4500H, 4700H or 7013? Aside from s few added features, would the little bit of extra power be noticeable?
Not really, while those would give you about 0.5 to 1 dB more juice, you can offset the effects by simply setting your volume 1 dB lower. That is, if your highest volume setting when using the 3600, 6014 is -10, then if you go with the 4500 or 7013, you could go up to -9 without degradation in distortions, and vice versa. For the extra juice to be meaningful, you need to use them with an external power amp rated at least 200 WPC, such as the Monolith, Outlaw, and Anthem's >200 W power amps. Even then, you will only gain about 3 dB more spl at the same distortions level at the most, and if you don't need the extra juice then there will be no audible effects if you go by ears only (okay, I am joking, but am somewhat serious too..)
Below are just my thoughts on the "whys", please feel free to ignore if not interested:
It is true that "all amps
don't sound the same" if expressed as a general statement, but they
do practically speaking once you get pass the point of diminishing return. Thanks to bench test sites such as ASR, we finally get to see while mid range AVRs are " higher compromised in terms of build quality", mostly due to having too many things jammed in one box and incurring higher costs in implementing many features, paying for the associated licensing fees etc., their amp sections are actually very comparable to separates with similar output ratings. Measurements don't lie, die hard audiophiles just refused to believe in certain facts such as:
- Extra power (I prefer "juice, or current, but okay say power..) not used cannot affect "sound quality", it just sits there and ready to help if and when called for.
- Distortions, harmonic, intermodulation etc., noise affects "sound quality" but only if above the threshold of audibility. Example, if your room's noise floor is 35 dB, and the max spl you listen to is 100 dB from you seating positions, then whether the THD+N is -80 dB or -100 dB will no matter to you, that's math, science.. 100 dB - 80 dB is 20 dB, THD would be at least 15 dB below your noise level, how can it have any effect??
Yes there are things that are not measured on those test benches, but that's because there is no point to measure things that don't matter, not that they can' be measured. Amps are designed by people who know the science, including how to take the necessary measurements to confirm the design goals are met, power amps are not that complicated, and have been build for too many years to have any available magic left, aside from the ways to have better efficiencies in terms of heat, weight, and energy consumption, without sacrificing accuracy.
