UE 700 vs Klipsch Reference S4i (which to buy?)

I can't comment on the Klipsh IEMs as I've never owned any but I currently own a set of UE700's. The bass is alright, nothing spectacular. If you want a bit more bass I've heard Shure is a good IEM to look at. I think the equivalent is the 315? Something like that.

Also, if I'm honest, while I do like how my UE700's sound I'm not overly impressed with the build quality. I've had to send them in twice due to cables becoming loose. I don't know if this is related to their being bought by Logitech and the quality dipping or if there's a flaw in the design. One of the reasons I'd say look at Shure is the cables are user-replaceable.

I should mention that UE replaced my headphones both times for free since they were less than a year old.

To me there is no question that the UE700 is going to sound better.  For one it has a much flatter frequency response making it produce exactly what you are listening to more accurately.  The S4i has a +15dB bump from bass to sub-bass ( 90hz ) which is simply terrible.  This is going to add bloat, sluggishness, and boom to the low end.  There is no doubt that the S4i is a bass heavy boomer.

http://graphs.headphone.com/graphCompare.php?graphType=0&graphID[]=3481&graphID[]=2261

The UE700 have their issues.  The first and most important is the build quality.  I avoid the UE700 because they are known for falling apart at the slightest tug of the cable.  I would not risk purchasing an IEM over $100 unless it was built like a tank.  We carry them around, toss them into a book bag, or snag them on a random piece of equipment.  We should not have to worry about the sudden destruction of a an expensive IEM from normal day to day use.

Take a look at the impedance curve for the UE700 vs the S4i.  See how the UE700 starts to wave around and show some dependence upon frequency after 1kHz?  This can be an indicator that the drivers are going to be hard to control.  They may still sound nice, but if the impedance is moving around on you your amp / iPod is going to have to work that much harder to control the drivers.

http://graphs.headphone.com/graphCompare.php?graphType=7&graphID[]=3481&graphID[]=2261

The UE700 do isolate better than the S4i which is a plus.

http://graphs.headphone.com/graphCompare.php?graphType=6&graphID[]=3481&graphID[]=2261

For the 500Hz square wave response you see that the S4i dips below 0 dB indicating some control issues.

http://graphs.headphone.com/graphCompare.php?graphType=4&graphID[]=3481&graphID[]=2261

Finally the 50Hz ( bass frequencies ) test show that the UE700 reproduce the 50Hz square wave much more accurately than the S4i.  See how the curve for the UE700 remains very straight and not curved?  This is a good sign of control in the bass region.  The S4i curves up showing it is going to have some issues at low frequencies say sub 40Hz.

If you are looking for a compromise as well as a well made IEM I would go for something like the Brainwavz M2.

Charts:

http://www.innerfidelity.com/images/BrainwavzM2.pdf

They do not have the build issues of the UE700 nor the sound issues of the S4i.  I highly recommend them especially if you want clear bass and really clear and up-front mids.  As with most IEM the treble rolls off, but not as much for the M2 as many other IEM like the Monster TurbinePro Copper seen below.

http://www.innerfidelity.com/images/MonsterTurbineProCopper.pdf

UE700s in this comparison, you picked very different IEMs to compare.

One other question is what will you be using as your source? I run mine direct out of my laptop and iPhone and it sounds quite good all considered. The big flaw is the build quality. It's countered very well by just how good they sound but if you beat your gear then this is not the IEM for you.

However, if you want something reference-grade then the alternative you mentioned might not be good, either. In that case I'd look at going Shure or, better yet, look for a used pair of UE Triple.fi IEMs for sale. You can usually find them for around $200. Yes, it's $50 than you planned but they are well worth the price. Plus, the build quality is outstanding and they have a removable cable. Bonus points, it's very common for people to convert them into CIEMs so you will have that option open to you should you ever wish to go that route.

I don't understand why you would come to a specialized headphone forum to ask about headphones if you're going to go by amazon reviewers... if that's your metric you might as well get some Beats and be done with it.

You didn't offend me, it just seemed silly to me to go to a site where you will find knowledgeable people in the subject you're researching, and then quote them opinions of regular people from another site... it kinda doesn't help you make a decision. Also, if you take the time to research, you will find that these kinds of threads are not "allowed" since there is already a lot of information for new people. You could, for instance, find comparisons between the UE700 and other IEMs that are not necessarily the Klipsch. For the same money as the Klipsch set you're looking at, you could buy this http://www.head-fi.org/t/595244/re262-for-sale which is regarded as one of the best IEMs you can get for the price. 

EDIT: I found you another very worthy set. If it were me I would get these instead of the 262s http://www.head-fi.org/t/593224/fs-sony-mdr-ex600

In terms of balance, the UE700 will leave the S4i in the dust...

As I posted in a thread I made, I emailed Klipsch and asked the difference between the regular S4is and the Reference ones. Klipsch said its only the new color and wiring.

UE 700 is superior by a wide margin.

Those who exaggerate UE 700's lack of build quality obviously have not owned the new revision and need to get their fact straight. I have both the old plug design and the new. While the old only lasted me 4 month (got replaced with a brand new pair no question asked thanks to Logitech, since sold it but then bought another pair). The new one is holding strong. I sleep with them in, I run/walk with them. I cannot tell you how many times I wake up in the morning with the UE700s under my body, being pulled/tugged/crushed all night, with the source - my iPhone 4, on the other side of the bed by the night stand. "Falling apart at the slightest tug of the cable" ??? Could not be further away from the truth. 

And I believe UE700's sound doesn't require any more praises. Just do a search. 

Sounds good, hope you like them