Here's how I see this, as I used to sell home stereos a few years back
when I was in college (at best buy, no less)...
Information gathered from observation and talking to every tom, dick
and harry who visited best buy to piss on our equipment...
Look at the THD number on a new reciever... the less the better, this
is the real bottom line spec as I understand it. THD = Total Harmonic
Distortion. This number increases exponentially as the volume is
raised...both numbers will be in the "specs sheet" for the new
reciever. You can ask at best buy for these documents because they
have one for each piece of equipment they sell...be polite but
assertive, you can get anything done.
Also, when you go to buy a reciever, feel how heavy it is. You WANT
heavy receivers. The advent of 'switching power supplies' (the things
they run computers off of, and almost everything else now) have kinda
taken over most consumer electronics, but you can find some receivers
that still use the big, heavy 'transformer' that it replaced... you can
tell if it has a transformer by how heavy the unit is near the power
cord. Onkyo, Yamaha, and Technics until they got bought out by
Matsushita/Panasonic around the millinium all had the transformers.
Don't worry about a phono input if you have a record player...you'll
never find a set of pre-amped inputs anymore... just buy a $30 pre-amp
if you have a turntable, it will degrade the sound quality, but IT'S A
PIECE OF VINYL, with little pits in it that creates sound... it's got
horrible quality anyhow.
Now, a few notes... a decent 2-channel (handles 2 speakers at once,
call it stereo for you old timers) is gonna run you almost the same as
a decent Dolby 5.1 which has the ability to not only run your basic two
speakers with the same power, but hook up another 3 and a subwoofer for
a real home theater experience. You can switch between 2 channel and
5.1 on every reciever I've seen...but you'll actually have to read the
manual with a 5.1 reciever, they get kinda complex compared to the plug
and they work 2-channel deals.
Technics ain't technics any more...don't buy anything made after the
late 90's with the technics brand expecting the same quality at your
older models...same for Pioneer, I have a pioneer that is really nice,
but it's definitely cheaply made. Their car equipment is still good,
but home stereos are...cheap seeming. sound is good though.
good luck... let me know if you've got any more questions or need info
on how to hook something up, that stuff gets complicated quickly.