Good volume booster...didn't see a great improvement in sound quality
933243
I got this at a marked down price and used it right away on a long flight from Miami to Vancouver.

While it did a great job of boosting volume, as for music quality, I didn't really see much difference.  I used it on a Sony Walkman for music, and on my Kindle HD 8.9" device for movies.

It will definitely give you twice the volume (or thereabouts) than you would normally get, depending on what device you have it attached to.  For me, however, some songs I listened to actually sounded better without it, particularly older songs.  (e.g. with "California Dreamin'" I could barely hear the vocals at all with it, but could hear them fine without it)

Battery life lasted a long time for me (about ten hours), it is well-built, and I like the on/off switch and volume control (same knob).  I also like the fact that the battery is easily replaceable and can be found for a very low price here on Amazon.

If you need a volume booster, it works great....other than that, I'd think twice. I'll be using it more in the days ahead and if anything changes, I'll update the review.
844212
Podcasts and music worked fine, but when I answered a call, I could barely hear the caller (yes, my volume was all the way up).

I will be getting a different one.
2071013
Excellent volume boost because most portables just don't have the amp power.....  Especially if you like a standard foam cup over the ear headphones vs. in the ear.....  I am going to be doing a lot of treadmill for the new year to lose weight....  I need to rock it baby!  Hightly recommened....
1369182
Sound quality for me is great, actually increases my ability to hear those on the phone. However I get mixed results from those hearing me. Some seem to hear me fine while others have a difficult time. Ok for the price.
4903754
I am upgrading my review to respond to some helpful hints sent to me by the Underwater Audio people. They were right, I was locking the buttons so they didn't work (by holding the play button too long). Once I figured that out, everything worked. The reason I didn't give it five star are the earbuds are lacking in volume. I found that using a swim cap over my ears helps tremendously with volume and clarity, but it still wasn't enough, so I dragged out an old pair of waterproof earbuds from Swim Audio that are better. Upgrade the earbuds and I would go five stars.
1247160
had hoped for better clarity in sound when turning up the volume- but, it's fine if you're using it in a small space - e.g., your office
1168108
IT does the job, but seems to lose volume over blue-tooth.
4390960
Very little appreciable improvement in sound quality or volume over the stock Sena SMH-5 speakers. And because they have 3 wires with anodized insulation, it was extremely difficult to splice them onto the stock wires that have 2 simple red/white wires.
2765175
Received the unit in a nice package, installation was a breeze.  Just plug and play.  Installed on my Win 7 HP Laptop to increase the volume of the sound.  It did not amplify the audio.  Only main difference in sound is that the speakers are now directed towards me instead of the desk.  So in that aspect I will keep it until I can find a better unit that really amplifies the sound.
902566
Volume doesn't go as loud as I would like; other than that, the product does exactly what I need it to do with not too many frills.
4937387
It did not increase the volume to level I want since I am a 60 y.o. person I require higher level of voice during my daily workout.
2276173
It fits well under my TV and is far easier to install than a surround sound system.  The sound quality is good but I found the feature that is supposed to tone down background noise is not very effective.  Over time I have found that, for some reason, after the TV has been on for awhile, the sound volume decreases and I have to increase it.  Then I forget that I have done this and when I turn the TV back on I get blasted with sound.
593056
I can't hear much difference with or without this. No big discernible effect. Not sure what it should do. Anyway, maybe it can make the sound louder, but no richer sound that I can hear. I'm using this on a 2011 17" Macbook Pro, Grado SR325 headphone.  (The headphone is not great BTW, my old Sennheiser was better but unfortunately it broke apart because it's extreme light weight and fragile).

I compare the sound between the laptop output vs. from this Fubar with the same headphone. Must I buy new Opamp and power supply to hear better sound? If this is the case, why don't they just make this thing with those components to begin with?
2744712
This item indeed helps with cleaner playing,  but don't expect to achive complete muring with it.
With high gain,  this does little with preventing mistakes and unwanted noise
3927429
Got a low level source, like an iPad? Forget about boosting it, there's no volume control. Watching movies? Bluetooth delays the audio stream a whole bunch. Lose the Bluetooth and use the aux input instead if you care about lip synch. All that said, the sound isn't bad at all.
2251616
Reception has greatly improved compared to earlier models and signal fade is nearly not an issue. Voice tuning is a nice addition and helpful. My main issue with these headphones is the extremely low volume. Even when turned to their loudest, they are still fairly low in volume. I am assuming the manufacturer limits the volume for various safety reasons, but it is annoying. Let the consumer decide how loud they want to play their headphones!! Increase the volume level and you would have a great product.
1640332
I've noticed that this headphone splitter will decrease the volume a little bit when you use it.  You can compensate for it by increasing your source's volume, but remember to dial it back when you're done using the splitter.  Otherwise you might blast your ears if you hook up a single headphone to your source.