[Sonic Defender]

  The Fiio Q5 seems interesting but the size is too large, kind of defeats the "ultra mobile" purpose of bluetooth....
 
I gave in to "the urge to know" and ordered an AT-PHA50BT to try it out (reads: to take apart). Lets see if the DAC is as good as the one in the E3.

Curious to learn about how you like the AT unit. Will you update this thread? I don't know about the Q5 being to big, I think it is designed for transportable more than on-the-go mobile. I really want a small footprint unit with Bluetooth that I can move around the house easily. The E5 was almost perfect, but the sound was just a little edgy for me, not very much so, but enough so that I noticed. Still, for the money the E5 was a smoking nice little piece of kit. The Q5 has solid potential as I think the DAC section is going to be quite good. FiiO has been working at affordable gear for a while now and they are starting to use the AKM family more which many feel has a softer sonic approach than the typical Saber suspects.

 

[AudioCats]

Got the AT-phA50bt, and did a little comparison with the Hesh's internal electronics ( using a L-3-770):
* A50 has a smoother and fuller sound,
* A50 has more power; the bass is stronger but can be boomy at times (not very clean bass). The Hesh's bass is drier but cleaner.
* A50 sound is very layback, almost as if it is intended to be used as background-music-player.
* Detail retrieval level is similar between A50 and the SkullCandy.
 
More phA50bt info is in the SoundBlaster E3 mod thread
http://www.head-fi.org/t/838371/creative-sound-blaster-e3-mod-adaptation#post_13391297
 
*** update: after about a week of daily use (at work, 3~5 hours per day), the A50 sound has opened up a bit and is now much better sounding than the internal electronics of the Hesh-2 (L-3-770), to the point that I am pretty much only using the A50 to drive the phones. Maybe I can move the larger battery from the SkullCandy and mount it to the A50 for longer playtime.

 

[AudioCats]

SkullCandy Hesh-3 wireless

I saw a pair of black SkullCandy in goodwill, in pretty good condition. I was curious of what it was, and it showed up as "Hesh 3" during the pairing process.

The sound is somewhat muffled and distant, not very "live". Bass is strong and numbing.
Maybe more clear than the stock Hesh-2 (from memory though).

bluetooth chip is CSR8635,
no dedicated DAC chip.

headphone amplifier chip is marked "4917AQ", looks to be a SGM4917.
-- C16 is charge pump reservoir
-- C20/21/22/23 are input caps
-- direct output, no output capacitors needed

The driver is glued into a hole in the baffle; the diameter, measured from the outside, is a little over 40mm, maybe a 40mm Grado driver can fit.

All electronics are in the right cup, the silver-bag battery is under the PCB.
The left cup is empty.

 

[AudioCats]

titanium Koss drivers into Hesh-3

stock driver removal:
--picked out as much of the old clear glue as possible
--added some isopropyl alcohol to the glue seam
-- pry the driver out using a small flat blade screw driver

Koss drivers: 40mm main body diameter with a 46mm dia rim. The 40mm portion (mostly) fits into the hole in the baffle. some cutting of the baffle material was needed to make it fit.

Then add hot glue to hold it in place.

The sound is pretty ok, clear highs with powerful bass, border-line bass-heavy. More clean sounding than the stock drivers.

One minor problem: left and right side don't sound exactly the same, the bass from the left side is a little more powerful yet loose, while the right side is tighter. Sound image shifts to the left. This probably have something to do with the different amount of free space in the cups: the right cup is stuffed with the circuit board and battery, while the left cup is mostly empty.