This is better than I thought it would be. Worst case is the T51p won’t have the excitement of the more “V”-shaped headphone sounds, but you’ll hear more of what’s actually in the recording. The more neutral headphones are most often a little bright (that’s what most users say), and can irritate on electronic and improvised music, but the T51p didn’t show any of that with these 3 tracks.
As the name gives away, these have an on-ear design instead of the over-ear design of most of Bose’s other offerings. The trade-off is that the On-Ear Wireless Headphones won’t be able to block out ambient noises as well, but some people might find them more comfortable. Plus they’re well cheaper than most other Bose wireless headphones. It should be noted that many reviewers, including Sound Guys, have praised the sound quality of these headphones.
Headphones can prevent other people from hearing the sound, either for privacy or to prevent disturbing others, as in listening in a public library. They can also provide a level of sound fidelity greater than loudspeakers of similar cost. Part of their ability to do so comes from the lack of any need to perform room correction treatments with headphones. High-quality headphones can have an extremely flat low-frequency response down to 20 Hz within 3 dB. While a loudspeaker must use a relatively large (often 15" or 18") speaker driver to reproduce low frequencies, headphones can accurately reproduce bass and sub-bass frequencies with speaker drivers only 40-50 millimeters wide (or much smaller, as is the case with in-ear monitor headphones). Headphones' impressive low-frequency performance is possible because they are so much closer to the ear that they only need to move relatively small volumes of air.
Total harmonic distortion: True, headphones with lower actual total harmonic distortion (THD) will sound better than those with higher THD. But the quoted THD numbers -- "less than 1 percent" -- aren't helpful in predicting sound quality. Listen to recordings of simply recorded acoustic guitar to assess the distortion of one set of headphones versus another. Some will sound appreciably cleaner than others.
Once you’ve got that all order, to put a cherry on top it would be ideal for the amp to play nice with my laptops (PC at work, Mac at home) *and* my *iPhone* 4S.  I haven’t found a headunit that works with PCs and iDevices.  If one doesn’t exist it would be a big plus for the amp to include inputs so I can get digital sound out of my iPhone (with the Pure i20 or its ilk) and into my headphones.
I will post some comments. If I forget let me know here. My main reason for ordering was the old pads on the 1350 wouldn’t make a good bass seal in colder weather, and Beyer has upgraded the pads on both the 1350 and the T51p, so I’m hoping for a better seal this time. I don’t know of any headphone that size that ‘s as accurate and detailed as those little Tesla models, and the carrycase is icing on the cake.
In-ear headphones are like earbuds but are an upgrade to them. These headphones fit into the wearer's ear canal and stay in place with the use of foam or rubber tips. These tips are available in custom sizes so they can fit each individual wearer. When a proper fit's achieved, in-ear headphones reduce outside noise and deliver sound quality at about the same level as over-ear and on-ear headphones.
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