As much as someone may want to doubt or have disbelief or be frustrated that they just bought the W4R, or that Westone has NOT "publicly" talked about sound changes......the W40 DOES sound undeniably different than W4R. Almost enough, to me, that I would almost consider it would have been worth calling it another IEM model # (well, I guess they did but didn't acknowledge sound changes).
Earphone Solutions, Westone rep Cody and 4-5 Head-Fiers that have picked up W40 all acknowledge definitive differences between W4R and W40.
Cutting to the chase there is definitely more bass and I find the presentation a little more closer and intimate. That's it. Some of the others have reported better clarity and wider soundstage but my memory has those traits equally good with the former W4R and without having side by side I just can't say. The added bass could be something as simple as adding 3-6dB to one of the bass drivers as a "boost" and, of course, the housing and cable are completely different which could also add to SQ changes.
IEM's that have amazing detail speed and transparency tend to be cold, analytical and lean on bass. That's the trade off. The other side of the spectrum has big full sounding and warm IEM's that lack speed precision and detail.
W40 really nails it right in the middle. Much moreso than UM3X/Pro30, W3, SE535. The overall signature is warm and lush and very non-fatiguing. The clarity and treble is among best in class at that pricepoint while the bass is more than adequate except for extreme bassheads. Nothing sounds out of place, no spikes, no boosts, etc. Imagine a very well balanced and neutral IEM with a large soundstage....now give it a very subtle and mild subwoofer effect to fill the sound out and you have W40. Unless you are a treble head and Ety fanatic, the W40 should please virtually everyone. It basically fixed the only real issue I had with W4R which was a bass effect that was a little on the lean side. With W4R the bass was okay and would not distort but it seemed I was squeezing every ounce of bass out of the earpiece. With W40, the bass comes across much more effortlessly.
Until I can plunk down $1000 for an IE800 or SE846 (the two I would have in mind) I am set with W40 and done! It's awesome and I have no faults to point out with it...it doesn't do anything wrong and doesn't really lack anything.
I'm also done with customs as the risk is too high that they don't fit right. There are no guarantees and high end universals are just getting too close in SQ to customs.
Edited by Spyro - 3/8/14 at 6:31pm