[Lord Voldemort]

Everyone knows 6.5 mm is better if one were to use headphones strictly for home use. However, is there a noticeable difference in sound quality between the two? 
 
Would the difference survive a blind test? 

 

[stv014]

1/8" jacks are more prone to contact problems. However, in the absence of those, I do not think they would sound different in a blind test.

 

[proton007]

Its just a form factor.
Just like a micro usb won't perform worse than the usual usb.

 

[maxmays1]

It depends. The purpose for the 6.5mm originally was the fact more current was passed through the lines(larger gauge wire), the jack sizes continued to become smaller as the purity of wires became higher as well as certain design flaws were fixed(not twisted, bent or stripped lines) and your were able to pass more current through a smaller wire configurations. now a days jack sizes mean little because the wire gauge size are unchanged from one cable to another. Most people only use a 6.5mm(1/4) plug as an adapter to certain devices that don't have 1/8 jacks.
 
BUT, in cases when you have fairly large wires for transferring high currents you would want to use a larger jack connection so you are not limiting heat and current transfer. Using a standard 1/8 connector on a line that has a very large load can cause some problems as you don't have a big enough contact area,even if you are using silver/gold plated plugs with large 24awg wired it would be a waste of wires if you are trying to transfer that power through that 1/8 pad. That would just be impeding the flow of current,and that current would be lost as heat dissipation.

 

[Blaz]

If you immagine components (transistors, opamps, ics, etc) at the (sometimes) almost-atom level, the size of the jack is practically irrelevant.

 

[Eisenhower]

The 6.5mm jack will sound much "bigger" than the 3.5mm jack

 

[Maverickmonk]

The 6.5mm jack will sound much "bigger" than the 3.5mm jack

When inserted into the ear canal , I personally find 3.5mm less fatiguing in such situations...


Seriously though, there shouldn't be an audible difference, although I prefer 1/4 inch just because it doesn't pull out as easily and feels more secure in general.