"The TDK BA100: Like Beige Wallpaper, But..."
 
...I Like Them!  I have all of about 4 hours of listening time with these headphones, but I don't think I need more to justify my thoughts.  They are BA (balance armature) drivers so burn-in is not a factor.  For this test I used my iPod Classic (no external amp and no EQ adjustments).  Many, many different tips were used to tweak the sound signature, but you may be surprised at what I used in the end.  
 

1. I started with the Shure Olives (they muffled the sound too much and didn't do much in the way of increased bass response).
2. The Etymotic foams were next (they sounded distant and veiled).
3. Followed by the factory silicone tips (not bad, but the seal was not quite right).
4. Next were the Shure yellow foams (terrible!).
5. Followed by the EarSonics bi-flanges (like Goldilocks, close, but not quite right).
6. Followed next by the Compy-like tips (they were similar to the Shure Olives).
7. Last were the Shure Grey Soft Flex Sleeves (perfection!).  The Shure grey silicone tips were almost identical to the TDK OEM tips supplied in the box, but the size large Shure tips just seemed to be a slightly better fit than the large TDK tips for my ears.  Go figure, TDK nailed it with the factory tips.  If they create a good seal in your ear, don't bother with anything else.  I only went with the Shure tips because of the slightly better fit/seal.

 
 
The Review:
 
My normal multi-genre mix of testing music was used to evaluate their performance (Radiohead, Bach, People Under The Stairs, The Shins, AFI, Royksopp and more).  This mix has been my go-to performance benchmark for about a year.  I'm going to draw comparisons between the BA100 and the Shure SE535 and Westone UM3X for this review.  (Disclaimer: I no longer own the UM3X, but the sound signature of that headphone is more "burned into my head" than any other headphone I have ever tried/owned so I can still use them as a basis of comparison.)
 
Let's start with the UM3X.  Since returning my UM3X due to a defect I have been trying to find another headphone for cheap that could remotely mimic their sound signature - warm lush lows, pleasing silky smooth mids, an intimate sound stage and non-threatening highs.  Of many recent low-end IEM purchases I have made I think that the BA100s come the closest with a few exceptions.  The UM3X has the best instrument separation I have ever heard in an IEM.  The Shure SE535s are a close second and the EarSonics SM3s are an even closer third.  As for instrument separation I find the BA100s to come in 4th, a distant 4th, but still in the same realm as the other three mentioned.  Now, more on that search for the ideal low-end UM3X clone I have been looking for.  I think I have found it in the BA100!  OK, you're not going to get the same lush, super-intimate vocal sound signature of the almost $400 UM3X, but you will about as close as you can get for 1/8 of the price (Yes, I got these for $50 on Newegg.com).  Like the UM3X, the highs are rolled off on the BA100 which makes for a very non-fatiguing listening experience.  The mids are not "in your face" like the UM3X but rather nicely placed.  The UM3X is like you are about 2 feet from the artist and the BA100 places you about 10 feet away.  The only part of the UM3X sound signature not represented well with the BA100 is the low bass response.  The UM3X are known for being warm and deep for a BA IEM, the BA100s just can't hang in that area.  For single driver BAs I am surpised at how well they do.  If you can get a good seal with them they will amaze you.
 
I would like to draw a quick comparison of the BA100 to the SE535.  Like the UM3X, the instrument separation isn't quite there, but it's still far better than any dynamic driver-based IEM I have tried.  The SE535 does a great job in the high end range, the BA100 can't quite keep up though - as expected due to them being a single BA driver.  In the bass department, things are much different.  I can't believe how good the BA100 is in the low-end compared to the SE535.  The SE535 have a little more authority, and more extension, but to the untrained ear they are fairly close.  I did find the BA100 slightly more lush and forward in the mid-range than the SE535.  
 
The construction - kind of a mid-range plastic feel.  Somewhere between a high end IEM and a cheap chinese varient.  The cable is flat and is similar to what you would see on a pair of Monster/Beats.  They're descent at staying tangle free, but not as good as the Shure or Sennheiser cables in that regard.  They're totally sealed, no venting.  As such, with the right tips they isolate extremely well.
 
What's included - a nice pouch with a squeeze-close opening, similar to the Klipsch pouches.  3 sizes of silicone tips and Complys (or Comply knock-offs) are also included.  Lastly, you get a shirt clip, a cleaning tool and some spare filters.  Nothing too exciting here.
 
Conclusion:
 
As a reference monitor the SE535 is still my #1 pick in the world and I would absolutely recommend them for that purpose.  The UM3X is the best IEM I can recommend for vocal & mid-range enthusiasts, and also for those with an extreme desire to focus on instrument separation and placement.  That being said, the BA100 is my new #1 pick for a sub $100 BA IEM that does everything well and excels at nothing.  
 
Like beige wallpaper, they are boring, bland, non-offensive.  You never get sick of them, they don't offend you.  You might almost forget that they are there.  The SE535s are like the Sistine Chapel.  You can't help but focus on the details.  There is so much detail from high to low that it can almost get tiresome trying to see everything in its right place.  The UM3X is like gorgeous black & white Ansel Adams print.  What it does, it does exceptionally well, but it's rolled off highs give it less character than a color print.  But, there are times were beige is the right choice.  When I want my music to take a back seat to (let's say) writing a headphone review like right now, they are the perfect choice.  They are so laid back and non-fatiguing that you can listen to them for hours and hours.  I recommend them for anyone looking to upgrade from cheap dynamic drivers, if you are looking for better instrument separation than you currently have, if you value the mid-vocal range and don't mind a little roll-off on both ends of the frequency spectrum.
 
TDK is out of line with a retail price of $199, they're good but not that good.  If you can pick these up for <$100 they are a good bargain.  If you can still get them for about $50 as I did, they are a no-brainer.

I originally purchased this unit with the intent on it being part of my home entertainment system.  It was eventually replaced by a Sony Blu-Ray player.  After remembering it had the ability to play SACDs I decided to purchase a few and test out the sound quality of this device.  I have to say that I am very pleased. 
 
I may eventually upgrade my DAC to allow the 980H to send a digital optical signal to the DAC and then to my desktop amp, but I am running the 980H directly to my Schiit Audio Asgard and am very happy.
 
If you can pick up one of these gems in good condition for cheap I think you will be pleased with its SACD performance.

 
Flat out, it's the best piece of audio gear I have purchased in my 2 1/2 year long audiophile career.

 

My previous DAC was an M-Audio Fast Track Pro run to an external amp, so that will be the standard by which I judge the HDP.  There frankly is no comparison between the two.  The HDP's internal DAC is world class compared to the Fast Track Pro.  It is extremely accurate without any coloring of the sound.  Separation and sound stage/placement is very well produced.  I get the impression that I am listening to exactly what the mastering engineer intended me to.  I am starting to notice how awful some of my recordings are, this DAC will show flaws in music like nothing I have listened to before.  On the flip side, I'm picking up sounds from recordings that I have never noticed before.

 

The amplifier was what surprised me the most about this device.  The HDP has a pretty small footprint on my desk, especially when propped up with the supplied hard rubber stand.  Because of its demure stature I wasn't expecting the amp to be great, but it is!  In fact I have just come to notice that Jan (from Meier Audio) actually re-sells the HDP on his website - I am imagining because he's currently missing a small desktop Amp/DAC from his product line (not to mention it's a great Amp/DAC).  This amp pushes my Senn. HD600s with absolute ease and I am no where near 50% of the max volume level for average listening (maybe 60-65% if I'm getting carried away).  This amp has great attack and great punch and is very analytical compared to other amps I have listened to.

 

I think that long-term I may acquire a tube amplifier to connect to this world class DAC for when I want a warmer, more laid back sound signature, but in the meantime the HDP has found a very happy home on my desk.  For $450, if you are just starting out in the Desktop world I highly recommend this device.

 

Equipment used for my review:

 

PC & MediaMonkey (FLAC and 320 MP3)  ::  Nuforce Icon HDP  ::  Sennheiser HD 600

 
The GOOD:

-- Size: very small and pairs well with a J3, iTouch, Sony X-Series, iPod Classic or similar device.

-- Battery life: as said before, simply amazing!

-- Construction: very solid and well built.  Great switches, with a firm feel and nice "click" to them

-- Form Factor: Second to NONE!  All of the inputs, outputs and switches are perfectly placed.

-- Weight: surprisingly very light.  This kind of caught me off guard.

-- Sound: The good stuff...

   1.  Bass: Great (setting "2" can be a little bloated on bass-heavy tracks)

   2.  Mids: Realistic and clear

   3.  Highs:  Also realistic without a hint of shrill or sibilance

   4.  Gain: I primarily use setting "1" for just about everything and setting "2" for my HD600s.  I have no need for setting "3" (which is probably designed for 600 Ohm headphones).  This thing has plenty of oomph.

   5.  Impedance: Aside from when I'm wearing my Grados I keep this setting on "0".  It tends to veil the highs too much for my taste.  I only occasionally put it on setting "1" when wearing my SR225i's.

   6.  Crossfeed: The best implementation of Crossfeed that I have heard so far.  Setting "1" is perfect for long listening sessions when you want to minimize fatigue.  Setting "2" is great for hard-panned music.  Both settings do a great job without significantly altering the sound quality.

 

The BAD:

-- The volume pot: there is a slight imbalance in the first 10% of the range, but this is common on almost all non-digital volume controls.  Heck, even my NuForce Icon HDP suffers from this.

-- Impedance: this setting is effectively useless because it veils all frequencies above 4,000Hz so much that it isn't worth using (sans Grados).

-- Hiss: With about 10 different headphones in my collection only 3 of them experienced hiss (and subtle at that, so I am being very nitpicky here).  The three that showed a subtle amount of hiss were the UE SuperFi 4, Denon AH-C710 and Sennheiser MXL-570; three headphones that really shouldn't be amped anyway so it's a moot point.  The others have enough resistance to negate any hiss.  

 

Overall, this amp is a 9 out of 10.  Right now, I can't think of a better portable amp on the market.