My only caveat is that if funds are limited then build just one good system at least to start with.
Agreed. Although relative, I think "funds are limited" to 99% of us.
I think most of us agree the hands-down most important part of any system is the front L/R speaker pair. Also key are the sub(s), and Center speaker, but the L/R are critical. That means we stretch our budgets to get the best L/R we can.
Now we have a system w/ the best L/R we could find/afford... and want to add a turntable. What will be the key components for the turntable? Right... the L/R speakers. If we go to another room, we either buy another pair of "the best" speakers or we settle for something else, (less expensive), we know and can hear are inferior to our main system.
For most of us, I suspect the choice is really between privacy and quality. (Except for those 1%ers, who we all know are the root of every evil in this country.
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)