[Pradeep]

I have recently purchased the Sennheiser HD650 headphones. I am using them directly on with my macbook pro. I am yet to decide on the amp/dac combo. Even with the macbook pro output the volume seems be fairly decent (when used with itunes).
 
With VLC running FLACs i can up the volume to 200% or more and get higher outputs.
 
My question is, as mentioned in the title of the thread, if the 6.3 mm jack is any better than a 3.5 mm ?
 
esp. in the case of high impedance headphones like the Senn 650s, does it make a difference?
 
Or is it because of the source or other components in between which causes this perceived difference, if any.
 
Like for example, most of the DACs and amps, the high end ones, have a 6.3 mm out which can also be used for a headphone which only has a 3.5 mm jack (with the help of an adapter).
 
Do they give a 6.3 mm out because it gives better quality or because the high end headphones have 6.3 mm mostly ?
 
I know 3.5 mm is better than 2.5 mm.
 
Is it similar with the case of 6.3 and 3.5 as well ?
 
Experts and critics please tell me if you have noticed anything perceptible  when switching between both. Also if possible, you can explain the science behind this.
 
thanks.

 

[ClieOS]

TRS jacks are all the same, regardless of which size it is in. No such thing as a 6.3mm jack sounding better than a 3.5mm jack or a 3.5mm jack sounding better than a 2.5mm jack as long as they all function mechanically perfect.

 

[violinvirtuoso]

The only reason a 6.3 mm might sound better than a 3.5 mm connector is if you use a bad adaptor.

 

[badmonkey]

No difference between any of them, but the chunkier connectors allow relatively finer mechanical connections and larger surface areas which would presumably tolerate corrosion for longer before problems became audible.

 

[Krav]

The 6.3 mm connector is also roughly 4x stronger (as cross-section area is proportional to the square of diameter). It is virtually impossible to bend it by hand and it is quite resilient to forces arising due to an accidental stomping on a cable - a very valuable property for gear which is subject to physical abuse in professional, especially live music, applications. 
 
Quote:

No difference between any of them, but the chunkier connectors allow relatively finer mechanical connections and larger surface areas which would presumably tolerate corrosion for longer before problems became audible.