Been done to death but.......

What is your budget and do you want the headphones to be small enough to be used on the move, or will they live at the office?

Good questions.

 The originals stayed in the briefcase for travelling emergencies, my Sennheiser PX100s live at the office and my Grados at home.

If I can get something to match or beat the PX100s then they will be relegated to back-ups and/or sweaty gym use.

Pricewise? Circa £60 but my arm is easily twisted  

I can recommend AKG 430's. 

I can recommend the Goldring NS1000, which I have as well as the PX200s and the Goldrings will sound much bigger with excellent clarity. But, they do leak a bit of noise, an issue if the office works in silence and you sit right next to a work mate.

i have the goldrings as well and they are brilliant for travelling. best thing you can get for less than £60 and trust me i have tried so many. 

use PX100s for the gym and for the office i have Audio Technica ATH-A500 which i can honestly say are the best i've ever had. tried AKGs but did not find them comfortable over long periods of listening.  

http://www.amazon.co.uk/AKG-K450BLU-K450-Headphones-Navy/dp/B001F6M5DI/ref=sr_1_1?ie=UTF8&qid=1291582436&sr=8-1

Owned the older version, you will love them for portable use. A very dynamic sound 

Thanks for the pointers.

The Goldrings and Audio Technicas look a bit on the large size for chucking in a briefcase. The AKGs look a bit smaller or do the pictures not give a true representation of the actual sizes?

Another point. My phone could not properly drive my Grados. Are the suggested earphones responsive enough for phone use?

Interesting thread. I'm in the market for new 'phones too. I was looking up to £250 and a few people recommended the Goldrings even though they are well below what I was prepared to spend. I'm yet to get in anywhere and listen to them though. Had a listen to the B&W P5s though at the weekend. Didn't think the soundstage was all the big TBH.

NS1000 seconded but these are still worth a proper demo to select which you prefer for your ears.

audioaffair:

NS1000 seconded but these are still worth a proper demo to select which you prefer for your ears.

Good point but it is nice to narrow down the field of potentials prior to demo. Thanks. 

The Akg's are very efficient and very compact, you should have no trouble transporting them

So. for audition the concensus appears to be:-

AKG 430 or 450, Goldring NS1000 or Audio Tecnica ATH-A500 v existing Sennheiser PX-200s. Got to be a noticable upgrade

Any others? Although 3 or 4 seems a nice amount for comparing.

Edit:- New theory. Use the Sennheiser PX-200s for travelling and dock the new ones at the office where they will be used most.

DavieCee:

Another point. My phone could not properly drive my Grados. Are the suggested earphones responsive enough for phone use?

I am surprised as the Grados are sensitive and easy to drive. However, many do feel that you do not get the best out of a headphone without an amp. For your iphone I would recommend you get a FiiO E5 and line out dock (LOD) cable which goes from the iphones docking port to the amp, so bypassing the iphones puny little amp. Both are on Amazon and ebay and you should be able to both for about £20 - 25. The FiiO is the best bargain in hifi IMO.

Thanks for the comments.

My Grados sound great at home driven by the Roksan or Caiman but the new headphones will mostly (95%) be at work where I am limited to PC headphone output or iPhone. Health & Safety  dictate that I can't plug anything else in. Given that restriction, the Grados don't perform to their best but the main problem is sound leakage. I may love my music but others don't  

I know this is a major compromise but I want to get the best I can. 

EASY

px200 

no brainer,.

small, closed and sounds great and you can get in white