[EdT]

Now I am wondering has anyone done a comparision of the 325, 325i, MS2 vs HP1, both are aluminium chambers, how much difference can just the driver make ?

 

[Rhydon]

Only the HP-2 and PS-1 have complete aluminum chambers. SR325i/MS2i have outer aluminum cups, but the inner is all plastic- think extended sr225.

There are also differences in dimensions and materials- i would rule out the HP-1000 series because of their unique larger drivers (also their drivers being a completely different construction)- that headphone and its chamber was tuned to its specific transducer. If you had an SR200 with HP1000 drivers- then you could play an even field for comparison- from what i know, even then there is a huge difference.

I would ask the question more so as to how does the PS-1 compare with the SR325i/MS2i- im sure many people would agree- theres a substantial difference as well.

I think the response would be yes, aluminum (all aluminum) does make a significant improvement on sound quality- since all the Grado drivers are 'relatively' similar (save for different substances painted on the surface and other small enhancements) in this case chamber material and construction plays a huge role on the headphone's sound.

 

[EdT]

Why doesn't Grado produce all AL chambers now ? it not that hard with CNC lathes today. Do we know if Grado even turns the AL cups now in house ? I doubt it, I think they are contracted to an external machine shop.