When you turn off the headphones and plug in the audio cable, MOOH is capable of a little nicer sound. Just barely. I was surprised how little a difference it made. The B&O H9 sounds quite different when wired into a decent DAP. But with MOOH, you get only a small improvement. However, when you are tethered to a device, the inherent tuning of said device comes into play. I suggest brighter sounding sources to combat the overly warm nature of MOOH. The Shanling M3s, Cayin N5II, and iBasso DX200 are phenomenal options that span most price brackets. The M3s and N5II aren’t exactly “bright”, but they’re close enough to neutral and have more than enough treble to help things out. The DX200 is of course the optimal choice, but is laughably overkill for the likes of MOOH.
In spite of its limitations, the M&O Beryllium Acoustic Bluetooth Headphone is a joy to listen to. It is easy on the ears, and has such qualities as to sweep you up into its rich, warm tonality. While it is not a technical marvel, I find it impossible not to like what I hear. If you love your music dark-sounding, and seek an inexpensive set of Bluetooth cans, I gladly recommend the MOOH-BE00BT. They will envelope you, as you relax into their cozy depths.