Disclaimer
Those of us sitting at the back of the bus who love our music reserve the right to practice a healthy dose of skepticism involving audio gear as we ride along the long winding road that is life.  Until said gear has passed our personal expectations thus meriting the mantra of GOOD GEAR any and all reviewers/reviews will be taken with a grain of salt. As natural born cynics we also expect those around us to practice a healthy level of free thought and approach our reviews with a healthy dose of skepticism. In the event there's violent disagreement concerning gear reviewed then please grab said gear throw it out the bus window grab your own much loved gear and by all means please join us fellow cynics at the back of the bus. Please be sure said gear being thrown out the window isn't mine.

                                                                        Intro
Before I begin this review I would like to make it perfectly clear that although I have IEM's that can be classed as bassy I'm NOT a basshead and the PoPo is far from my sound signature of choice. The PoPo is your standard colored warm sounding IEM with an overly emphasized low end and roll off in it's highs. Note presentation is thick and note decay is rather slow. The end result the general sound signature is laid back and non fatiguing. It's a pleasant enough sound but because of how it's been tuned this little IEM for me is quite limited in what type of music it shines with. The PoPo is the type of IEM that lives and breaths souley in basshead territory. To my ears although it does slam pretty good and could be called a bass cannon I prefer to call it a rumble monster, more on that in a bit.
 
                                                                                                                                       
Specs
Type: Dynamic, In-Ear
Size of driver: 9mm
Impedance: 16 Ohm
Sensitivity: 110db
Maximum SPL (Sound pressure level): 127db(1khz, 1 Vrms)
Frequency response: 20-21khz
Earphone jack: 3.5mm
Cable length: 126cm

                            Accessories Formfactor  and Comfort
The PoPo comes packaged in a small minimalist box, very Apple like I may add. Inside you get the PoPo, a shirt clip, a large assortment of tips, 3 sets of different tips in (S,M,L) of regular ear tips bi-flange tips, and triple-flange tips, and NO pouch. The plethora of extra tips ensuring a proper ear fit for the vast majority of users is a very nice touch by HiSound but the lack of a cheap one dollar poach is a bad omission for an IEM in this price range.

Form factor wise this little IEM is quite well put together. The cables are sturdy and non microphonic and the strain reliefs seem quite solid. The wood housing made of African Rosewood is quite nice and makes the IEM look quite beautiful. The PoPo plug is a 3.5 mm straight plug which I'm really not fond of, I prefer a 90 degree angle plug on an IEM, but that's just me and it's far from a deal breaker. One thing that I really didn't like about the PoPo formfactor was the omission of a neck slide adjuster on the IEM. A neck slide adjuster in this IEM's price range should be a no brainer and I was rather surprised at this omission.

Comfort and fit wise these IEM's are up there amongst my other stable of easy pop in forget about them and go IEM's. The large selection of tips guarantees a good fit for the wide majority of users out there. Isolation, although vented they isolate well enough that you'll have to keep your eyes open or wind up under a car. My Sony MDR EX600 is vented and I'm rather impressed how much better the vented PoPo can isolate out noise next to my EX600. Overall I'd have to say the PoPo is a well built comfortable IEM and HiSound did an acceptably good job with it. If they had included a poach and a neck slide adjuster with the PoPo I would have said an excellent job and not just a good job.
 
                                               Soundstage             
Usually when I review an IEM I only quickly touch on soundstage near the end of a review but with the PoPo I have to make an exception because soundstage for this 60 to 70 dollar IEM is done exceptionally well. It's not the most expansive or detailed soundstage I've ever heard but it still easily dwarfs the soundstages of other similarly priced IEM's. Although the PoPo is thick lush bass heavy sound signature overall instrument positioning is excellent and overall imaging is also excellent. Left right front and back instrument separation and positioning is very very good on this IEM. The result sound layering becomes very good and I'm hearing a very good 3D like presentation that I would class as above par for this tier of IEM. I have to say it's very nicely done and I'm impressed with the PoPo's soundstage capabilities.

                                                                          Highs
The highs on the PoPo aren't to bad for this tier of IEM. They're generally smooth and non fatiguing and I'm noticing some roll off in the upper treble region. There is a bit of sparkle up top I'm glad to say and it can smash and crash when the music demands it. It's a pretty traditional approach as far as highs are concerned for a bass head IEM with deep bass extension and it's what I expected from this tier of IEM. Detail retrieval is generally good although not great. In all fairness to Hisound the PoPo wasn't created for the neutral detail obsessed audiophile market. It was created for the young fun loving mainstream pop rock and electronica market.  

                                                                           Mids
In a nutshell the PoPo mids are rather unassuming. They don't necessarily do anything wrong per say but they don't do anything to really make them stand out either. Guitars on the PoPo come across as thick and crunchy and detail retrieval can sound a little smeared at times due to it's warm bass dominant tuning. Vocal presentation is presented slightly forward and sound rather nice and I'm especially liking how female vocals are presented. Upper mid range to lower high range transition seems good and sibilance control is very good. Lower mid to upper low frequency transition though I'm not to fond of and I'm noticing some heavy leaching of bass into the PoPo's lower mids. End result part of the mids feel veiled and for a lack of a better word masked.
 
                                                                          Bass
What makes the PoPo stand out amongst other Bassy IEM's is the incredible amount of mid/sub bass which really reaches down deep. I've never heard an IEM with so much rumble before in my life. My Turbines, X10 and S4 don't even come close to the amount of rumble the PoPo can generate. You listen to a bass centric song with deep bass on the PoPo and it feels like the bass completely envelopes the listener. The only way I can describe the PoPo bass is it's an incredibly deep shaking enveloping rumble monster. Although interesting and rather fun at times there's way to much of it and because of this the PoPo for me becomes quite limited in the kind of music it can play. I'll say it, on a lot of my electronica, trance, and some pop rock the PoPo's overly enveloping bass can be fun but my God it's not something I'd want all the time and I definitely don't want it with my rock metal or jazz.

                                                        Final Conclusions
I'll be straight up and honest about it, as stated at the beginning of this review the PoPo is not my kind of sound signature. This little IEM is a bassheads delight come true though and for them it'll work very well. For what it brings to the table sonically it's a well priced IEM. My only point of contention with it formfactor wise is for it's pricing it should have a neck slide adjuster on it's Y split or at the very least a cheap pouch. For the basshead looking for a good entry level IEM the PoPo I would say is worth looking into. For everyone else though I can only say move along folks there's nothing to see here.
 
                                                                 

                                                                        
                                                                     Disclaimer
Those of us sitting at the back of the bus who love our music reserve the right to practice a healthy dose of skepticism involving audio gear as we ride along the long winding road that is life.  Until said gear has passed our personal expectations thus meriting the mantra of GOOD GEAR any and all reviewers/reviews will be taken with a grain of salt. As natural born cynics we also expect those around us to practice a healthy level of free thought and approach our reviews with a healthy dose of skepticism. In the event there's violent disagreement concerning gear reviewed then please grab said gear throw it out the bus window grab your own much loved gear and by all means please join us fellow cynics at the back of the bus. Please be sure said gear being thrown out the window isn't mine.
 
                                                              INTRODUCTION
The Westone 4 is a nice little piece of gear whose voicing is wonderfully realistic. In a nutshell it's sound signature is warm slightly south of neutral with polite highs fluid mids and quality sounding full bodied controlled punchy bass. It's an IEM that some audio puritans, read audiophiles, may choose to forgo for more capable offerings but many IEM collectors music enthusiasts and especially newer main stream music lovers will find a fun delightful listen. The Westone 4 isn't what I would call a true neutral IEM by any stretch of the imagination and in my eyes lies firmly in the warm south of neutral realm. It has it's own very distinct sound signature and although I would class it as slightly colored sound it's far from the pricey bloated and unengaging sounding IEM's found on the shelves of box stores. If thus far this introduction has peaked your curiosity then please read on.
 
                                                      FORM FACTOR FIT AND FINISH
Form factor and build quality on the Westone 4 is excellent and rates easily as one of the best I've ever owned for an IEM. Isolation is also the best I've ever encountered and rates far ahead of my other IEM's. I can easily wear these walking down the street during rush hour or on a bus and not be disturbed by outside noise. When I first bought these IEM's I was shocked how light they were in my hands. Their lack of weight ensures a great fit and I'm finding attaining a seal is easy and once they're in I can forget about them. A word of caution, these IEM's are designed to only be worn over ear. Not a concern for me considering I wear all except one of my IEM's over ear but I thought I'd mention it for the users out there who prefer wearing their IEM's cable down. Strain reliefs on the right angle jack and the IEM housing is sturdy and appears at first glance strong enough to last the test of time if the IEM is taken care of. The braided cable adds a nice touch of class to the general appearance of the product and although it appears thin at first glance I'm happy to say upon further inspection it appears quite sturdy and quite pleasent to the touch. Microphonics are thankfully practically none existent and tangling seems minimal. I know enough people on here consider Klipsch IEM's the most comfortable on the market but personally I think the Westone 4 is easily on par with the Klipish product line as far as comfort is concerned. With form factor and fit now officially out of the way lets now move along to the most important part of this review, sound.
 
                                                                           HIGHS
The Westone 4 highs I would describe as inoffensive and polite. There's little to rave about these highs and I can only describe them as doing their job well enough. Detail on the top end is generally decent nothing to write home about but decent none the less. At times while listening to some jazz hard rock and metal songs I've found myself left wanting due to cymbals sounding buried and distant compared to the rest of the music. The listener whose ears have an aversion to energetic highs will love the Westone 4 highs but those who like an edgy more energetic treble region will be left wanting. The good news for the edgy treble lover is the highs can be coaxed to come out and play for those with the patience to do a little tip experimentation. They won't shine like an IEM with nicely extended highs of coarse but they can be made quite tolerable. My guess is Westone decided to play it safe and tuned the highs to sound smooth. In some ways it's not a bad idea but in other ways the trebles short comings can become painfully obvious.
 
                                                                               MIDS
The mids of the Westone 4 for me is a completely different matter altogether, they're beautiful. Although not the most detailed I've ever heard they're overall tonality and fluid like transition between the low and mid frequencies cause these IEM's to excel past many other more technically capable gear. The warm lush slightly laid back presentation of the Westone 4 coupled with the very slight mid bass rumble of it's lows serves to further accentuate the mids into a well rounded mid and low frequency tag team package. Vocal driven music will especially shine on the Westone 4 and I found myself full of goosebumps listening to the very beautiful voice of Melody Gardot's My One And Only Thrill and Worrisome Heart albums. Guitars have a nice resounding crunch in these type of mids and sound lively pulling the listener into the heart of the music. Note definition overall is good and I'm finding horns and string instruments also sound quite lively and above all very natural.
 
                                                                             LOWS
The low frequencies is where the Westone 4's second one two punch lies and is eclipsed only by it's mids. Percussion is excellent on this IEM and it can punch with the best of them. I'd like to take this time to point out in no uncertain terms that the Westone 4 IS NOT what can be classed as a bass head IEM. Although Westone chose to use two of the Westone 4's four balanced armatures to render the low frequencies they thankfully chose to emphasize quality over quantity. The bass is well extended and detailed, meaning mid bass rumble is present, and note decay is acceptably quick meaning it's tight and well controlled. Add in a nice slightly lush warm bodied sound and you have bass response that meshes in beautifully and unobtrusively with the Westone 4 mids. Overall in my humble opinion a very nice coherent presentation. Alain Caron's Le Band album especially shines on the Westone 4 lows and I'm finding myself tapping my toes and smiling as I follow along to the beat of the energetic bass.
 
                                                                   OTHER SOUND BITES
Other attributes that bear mentioning, soundstage on the Westone 4 is very good. In my experience to much air between instruments will make the general sound presentation feel disjointed while to little and it feels like the band is tripping over one another. Thankfully neither is the case for the Westone 4 and I'm quite happy with it's soundstage. Instrument placement is also very good and I'm finding it quite easy to zero in and pinpoint different instrument placement even in very busy sounding passages. General layering of sound is good and the feel of a 3D like sound effect is pretty good although not perfect. The Westone 4 will respond not to badly to amping but it's not a must in my book. My personal experience as far as amping is concerned is the Westone 4's sub bass can be be brought out just a tad more and it's mids tend to sound just a touch more refined. Mind you this isn't a night and day difference so your mileage may vary depending on the mobile gear you're using.
                      
                                                                    TIPS ON TIPS
This next section isn't meant as a review and is only meant as a general guide to try and help manipulate the sound signature to the users own preference. I find the Westone 4 fits nicely as a all arounder but it can be further tailored and refined with proper tweeking using different tips. This is just my personal experience of coarse and as such your mileage may vary. As a general rule right now I've gravitated towards two different tips the supplied Westone white tri flange and the large Comply foam tip. I'm finding when I want to enjoy bass centric music a deeper seal brings in far more bass and as such the tri flange is my tip of choice. It seems to bring out a little more of that sub bass and adds just a touch more rumble to the general sound. The drawback is it kills the highs and recesses them more but on the plus side it also kills the sibilance in overly harsh recordings. When enjoying music such as metal/rock/jazz I'm using the Comply tip to open up the treble a little bit more. I'm finding the Comply brings forward a little more energy in the top end and the upper mids become a little more lively. The drawback, that touch of rumble dissapears and the mid centric nature of the IEM becomes a touch less pronounced all the while more sibilance will creep in with harsher recordings. As stated before your mileage may vary though so don't be afraid to experiment.
 
                                                                          IN CLOSING
My final thoughts as far as the Westone 4 is concerned is it's a very good IEM. It didn't knock me on my butt per say but it did surprise me and took some of my music to a higher level. As of now the Westone 4 will be taking up permanent residence in my back pack supplanting my UE700 as my always on the go IEM. It's excellent isolation excellent comfort and ability to handle different genres of music well enough make it a no brainer as far as I'm concerned. I have no problem recommending this IEM to others but I have to point out my recommendation is a guarded recommendation. As stated above the treble region of this IEM is not the type of treble a treble head detail fanatic craves. As such choose wisely when deciding if the Westone 4 is a good investment. For me personally I see the Westone 4 as the jack of all trades and master of none sort of IEM. It's not the most technically capable IEM for it's price range but it's so much fun I can't help but listen to it.
 
This is DigitalFreak now closing this review. I hope you found it informative and a fun read. I now step aside and look forward to reading any questions or comments anyone may have.
 
Regards
D.F.

OK I just bought myself a pair of MDR XB 700's 3 days ago to see for myself what all the fuss was about.
 
Positives:
Overall so far I'm pleased with my purchase. Although I find these cans generally speaking a fail with metal/rock/grunge they completely own when they're used on the electronica/rap genres. These cans have some very nice deep bass slam and I found the bass to be generally well controlled and acceptably defined for my tastes. The highs have passable detail without being shrill and the mids are generally also good. I'm surprised how good the bass slam on this thing is. You get some very nice low frequency slam without it being bloated, muddy, and most importantly the bass doesn't bleed and overpower the mids and highs. The form factor is generally nice and I was glad to find out that a nice leather poach for storage is included when you buy the headset. Although these cans are mostly plastic they don't feel flimsy in my hands and feel like they will last a long time with proper care. The fit is excellent and the clamping force for my head is just right. There may be better headphones out there that can do the bass head thing better but considering most of the competition is pricier the XB 700's are a steal for the kind of sound signature your getting. These cans sound signature may not be prim proper snooty audiophile grade sound but they are a incredibly fun sound signature to groove to and play around with different electronica songs with.
 
For those who already have the XB 700 get the album Tweekend by The Crystal Method. This album sounds so freaking neat on these headphones. I couldn't help but smile while I listened to it on these cans for the first time.
 
Drawbacks:
I wish Sony had included an alternate product package with this model. I would gladly have thrown an extra 10 or 20 bucks down if I could get a decent protective box for this headset instead of the standard issue leather pouch. These cans also lack a 1/4 inch plug so if you want to hook up (depending on your gear) you'll need to have your own 1/4 inch jack on hand. Although these cans are being marketed as mobile headphones they are far from ideal as on the go cans.They're rather big and don't fold up so you'll need room in your bag for them and because they only come with a soft poach you'll have to be careful of hard knocks etc if you don't want to ruin them. These are not a good choice if you're seeking an all purpose do it all set of cans. If you like your industrial/metal/rock/grunge overly bass heavy then OK whatever floats your boat but for most people these headphones won't work for certain genres. Put simply these can's aren't a headbanging headphone they're cans meant for the bass head not the rocker. They're also not audiophile headphones so if you want to dissect music get a pair of mid/higher end AKG's, Sennheisers or Grado's. As said above in the Positives section if you just want a fun sound signature to groove to then these are the cans for you.
 
The LoL section:
 
When I first bought these cans I couldn't wait to get home and listen so I ripped open the packaging and plugged them into my iPod and wore them while doing my errands for the evening. In a span of two hours I had 1 guy say "nice headphones, must be nice to have headphones that double as pillows" and 2 friends who I ran across commented "hey princess Leia when did you get a sex change and become a man". Be prepared for a little light ribbing when wearing these in public especially if you have friends who are Star Wars geeks.

When I first heard that Bowers & Wilkins had entered the mobile headphone market I was very excited. Anyone who knows anything about high end audio has heard the name Bowers & Wilkins. The company has a long distinguished history amongst the audiophile community with their excellent product line of stereo speakers. I've never owned a pair of B&W speakers but I have been lucky enough to hear a set and I was blown away at the sonic signature of their stereo speakers.
 
PROS:
First lets get the pros out of the way. The build quality on these cans is excellent. They have a very firm very solid feel in your hands and if properly taken care of they will last for many years to come. B&W also provides a sturdy display box and a nice travel pouch to help protect your 300 dollar investment. Included in the pouch is a spare cable and a standard 3.5 mm head jack. The fit of the P5 is incredibly comfortable on the ears and have got to be the most comfortable set of cans I have ever owned. I have been able to wear them for 3 to 4 hours on end and have felt no discomfort whatsoever.
 
The passive noise canceling capabilities of the P5 is very impressive. The headphone cuffs and the fitted leather over the cuffs act like a sort of tight sealing suction cup over the ears allowing no noise leakage in or out. I've sat on a packed bus with these cans blasting away and have not disturbed anyone around me. I've even worn these cans blaring away in a library where I was in close proximity to the working librarian and have had no requests to turn the volume down due to the noise leaking out into the surrounding environment. I've walked down a busy sidewalk with rush hour traffic zooming by barely 3 feet away from me and have been able to enjoy my music undisturbed by blaring horns and rumbling buses and trucks.
 
Cons:
The con is unfortunately where it matters the most which is the sound. Before I begin I want to make it absolutely clear that the P5's are good sounding headphones. The problem is when I think Bowers & Wilkins I expect great sound not just good sound. When I first tried my P5's out I was left for a lack of a better word disappointed. I did try to give them a chance though and proceeded to loosen the drivers up (burn) by playing music nonstop through them for a good 50 to 60 hours. I also chose a wide selection of different genres to see how they would perform. Although I did notice some improvement the overall sound was still lacking.
 
Depending on the music the bass seemed hollowed out and not properly balanced with the treble. In certain spots the mids and highs sounded grainy and other times almost nonexistent due to the bass drowning everything around it out. Vocals on other headsets that sounded like the singer was standing 3 feet from me on the P5's sounded distant and even at times tinny. Transparency was lacking on so many of my song selections. One band I've always loved is Epica (Symphonic Metal) and on the P5's I found many Epica songs so lacking in transparency it was almost painful to listen to.
 
It's not to say the listening experience was all bad. For whatever reason when I played various songs from Disturbed (alt Rock/Nu Metal) I was pleasantly surprised. For whatever reason that bands sound or maybe just how the music was mixed paired with the P5 very nicely. Vocals were clear in your face and mids and highs seemed acceptably clear with the bass seeming less hollowed out. I also took the liberty of running various different mixes of Darude's (Electronica) Sandstorm through the P5's and was again pleasantly surprised with good mids, highs, and less hollowed out bass. Matter of fact the P5's seemed to mesh well with most of the electronica and dance songs I threw at it.
 
Final Thoughts:
I don't hate the P5's but I'm not exactly in love with them either. As a mobile headphone they offer a extremely comfortable fit, excellent passive noise canceling, and have a very solid form factor that will last for years to come if the consumer takes care of them. What bothers me the most about the P5's is for 300 dollars there are far better sounding headphones on the market. I'm not a huge fan of Dr Dre Beats headphones but given the 300 price tag a future consumer might consider Beats headphones as a slightly cheaper alternative. Sonicly the P5's aren't that much better sounding then the entry level Dr Dre headphone. Klipish also just recently put out what I'm told is a good sounding mobile headphone at a good price point.
 
Does this mean I'm going to dump my P5's? Probably not. I think they're generally good headphones. My main problem with the P5 is I think they're overpriced for the sound quality they offer. I also can't help but think that if Bowers & Wilkins were going to put out a headphone they should have taken more time and done better sound benchmarking. Considering this is a product with the Bowers & Wilkins logo on it I expected far more from a company whose name has become respected for putting out  great products with great sound.