The PSB M4U8 is an over-ear, noise cancelling Bluetooth headphone. It also represents one of the few occasions where I have been able to review the successor to a product I have already tested. When it appeared six years ago, the original M4U2 was a very significant headphone. It was the first such product from PSB and, unencumbered by any tradition or preconceived ideas, made a very clever noise cancelling headphone. It was a milestone product for me as it was one of the first to use a microphone inside and outside the enclosure to better judge the noise cancelling effect. This dramatically reduced the ‘confusion’ that the inner ear can experience and made for a much more comfortable experience. I liked it very much and awarded the M4U2 a Best Buy.
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