[James Myers]

So I've decided to buy a new set of gym/travel headphones. Currently considering the Oppo PM-3, but I would prefer something with removable pads.  Id like something that I can replace the pads on down the road when the pads inevitably wear out.
 
What I'm looking for:
 
Closed back, more portable plane/gym friendly than the K553
Budget: 300-400$ (not firm)
Easy(ish) to drive
good noise isolation
Signature: Neutral, with a tilt towards the dark side of things.  I'm very treble sensitive, especially sibilance.

 

[jodgey4]

You should consider IEMs for your use. Not many full headphones do well with the gym IMHO. But I would suggest the B&O H6 and B&W P7 regardless, though they may not have enough clamp.

 

[James Myers]

  You should consider IEMs for your use. Not many full headphones do well with the gym IMHO. But I would suggest the B&O H6 and B&W P7 regardless, though they may not have enough clamp.

I'm hesitant to spend much money on IEMs, as a few pairs have found their way into the washing machine in the past.  They seem to get lost in the folds of gym shorts.  Maybe there are IEMs that aren't so small?  .

 

[jodgey4]

That happened to me until I got some from HA that come with a hard case... much harder to forget!

 

[Beyakusenn]

  I'm hesitant to spend much money on IEMs, as a few pairs have found their way into the washing machine in the past.  They seem to get lost in the folds of gym shorts.  Maybe there are IEMs that aren't so small?  .

How about Custom IEMs? If you get the moulds done properly you'll get: perfect fit, great comfort, large IEMs that are not easy to forget, great passive isolation and most likely great sound quality. I got mine with removable cables so even if I make repetitive movements that might damage the cable over time (like running or cycling), that won't be much of a problem.

 

[James Myers]

  How about Custom IEMs? If you get the moulds done properly you'll get: perfect fit, great comfort, large IEMs that are not easy to forget, great passive isolation and most likely great sound quality. I got mine with removable cables so even if I make repetitive movements that might damage the cable over time (like running or cycling), that won't be much of a problem.

Where would I buy something like that?
 
And How would a 300$ pair of IEMs compare to a 300$ pair of over-ear HPs?

 

[jodgey4]

IEMs usually have more balance and detail IMHO, at the cost of soundstage. Just IME.

 

[Beyakusenn]

  Where would I buy something like that?

There are various producers of custom IEMs. To get them made, you first need to have the moulds done. These usually cost less than $15 each (so less than $30 for the pair).
After getting the impressions done, you send them to the manufacturer with the printed receipt and if you already paid the costs, they will start making the CIEMs. It might take a while before they arrive, but the result is satisfactory. At least it was for me.

Spoiler: Things to take into account for the moulds

Make sure to ask which brand of silicone they use. Producers often specify on their website which brands they prefer for the material of the moulds.
The mould should be up to the second bend of the ear canal and if you want removable cables, they prefer for the mould to have some excess material on the outside.
Your mouth needs to be open for the best possible fit. You should get a bite block, but don't bite hard on it. Try to hold it as softly as possible between your yaws till the silicone dries.

 

 
And How would a 300$ pair of IEMs compare to a 300$ pair of over-ear HPs?

I have the Custom Art Music One CIEMs with removable cables (including moulds €250) and the Beyerdynamic t51p (€269 new). They are both great performers in their own fields imo. The t51p is the best portable on-ear headphone I have tried (and I tried many) and the Music One is considered to be one of the best single driver balanced armature IEMs.
 
The t51p does have a larger soundstage than the Music One, but it's not very large either so the soundstage is not the most significant difference for me. The balance and detail of the t51p are very good to my ears. I think the Tesla drivers are responsable for that. Still, I prefer my Music One for portable use in general because they are much more practical and for long listening sessions more comfortable as well. The sound is different to the t51p, but not significantly better or worse.