Just chiming in on the goodness above - I *finally* did manage to get my hands on a pair of PS500's for the evening.
So here's a really short and sweet comparo' with the RS1i :-
Bass :-
More mid bass impact on the PS500, definitely agree with Martin that this new-ish Grado is the first one to break out
on the dance floor, I'm more of a jazz man these days but this trait did jump out on a few electronic ambient tracks.
Bass timbre is the difference between the two, the PS500 has a small sub like quality to it whilst the RS1i has
a deeper, less impactful type of wooden Hi-Fi bass - which is better? You decide
Mids :-
You don't realise how forward the RS1i sounds until you have a PS500 on hand, there is nothing distant about
vocals or other middle frequencies on the PS500 but everything sounds a good row or two more forward on the
Reference Series 1 - this in itself might the single deciding trait that makes the PS500 appealing to folks who
at heart are not total Grado aficionados. I find the RS1i more intimate but that's my subjective preference,
I can recommend and could certainly live with the PS500 presentation here.
Highs and sizzly treble :-
This is perhaps where I really do prefer the RS1i - it extends into those saxophone highs with aplomb and
control, the PS500 rolls off a tad and in some cases can exhibit a little smidge of glare by comparison - again,
nitpicking here and you would really only notice with a headphone such as the RS1i or Shure 1840 that by
comparison do a slightly better job.
Imaging :-
RS1i again for me - it surely must come down to the cup size and venting - there is certainly more
volume in the all-wooden cup, my reference for an imaging test is The Doors - The End (Heart of Darkness edition)
at the beginning a sweeping tone images from left to right and then back again - the PS500 does a great job
but to my ears it does not manage to make too many gains from the 325i in this respect - there is more air
and spatial sense with the RS1i.
Overall? There is no winner - RS1i would be a recommendation for someone who really wants the most forward
mids in the business, fancies jazz, female/male vocals - no electronic or dance or anything top #40 really.
The PS500 is perhaps the more complete listen, its not as bright overall - has a more relaxed presentation
and is ultimately more conducive to modern releases.
Focker mate, if you're reading this - I know you still have your eye on the RS1i - my advice? It's not going
to be a $695 leap, I know you're a progressive bloke who is happy to take the small differences but my advice
is that for exactly the same cash - live large, carpe diem - seize the day and just offer up that some money
for a barely used GS1000i - reasoning? SR80i, SR325i, PS500, T1 - are excellent cans in their own right
but where is the sonorous soundstage and dramatic big bass? GS1000i