Youve got yourself a nice Receiver - congratulations!!
Just a few bits from the top of my head....
The key here is to experiment, and have a ball doing so!!
A camera tripod is a great tool to have for the YPAO. You can get one with retractable legs pretty cheap. Retractable legs are handy as you can adjust the legs to be at different heights when setting the mic up on YOUR chair.
When you run the YPAO....
Prior -
Set "Speaker Size" to SKIP. Go into Manual Setup and adjust these settings prior to running YPAO.
Ultimately (IMO) you want to have all your speakers to small, and set BASS OUTPUT to SUB.
However as your Subs capabilities are a little questionable at the moment, you may want to experiment with fronts set to LARGE and Bass Output to BOTH until it's upgraded.
Manually set crossover to the freq you desire - this is really going to be dependant on your rears at this stage. 80Hz (THX) MAYBE a safe place to start depending on your speakers abilities. You may have to experiment with this. If you run YPAO in this area, it may be set a little highish. I'd say YPAO will also set your front speakers to LARGE if you run the test.
IMO and situation, the 1500 benefits from the extra headroom obtained from having all <60Hz material delegated to the sub.
Nemo's Whale sceen and the Rocket exiting the cave in the Incredibles were two handy pieces of media for experimenting with this.
Play with the EQ settings. I'd say with the combination youve described and your specs for your fronts (???) being 35Hz - 20kHz @91dB, set the EQ to front till you get the rears updated... Post speaker update, try FLAT (worked for me).
Excluding speaker size and crossover, my Sub distance was the only thing I had to adjust manually - it was +2-3 metres out.
Experiment with different settings, perhaps leave the EQ settings at FRONT while you establish the crossover point for your sub (remember this HAS to be based on the speakers that have the least amount of ability to reproduce BASS on your system). Depending on the material you listen to, and your personal tastes, do whats right for YOUR ears!!
There are a few threads about with setting up the 1500 - I know I bent some peoples ears a few moths ago with a zillion questions.
Enjoy your purchase, Oh - and setting it up!!
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