Noise reduction totally ineffective. Almost no difference noise reduction enabled or not. Tried by plane, train, in the subway: totally ineffective. I also have a BOSE noise-canceling (much bulkier and much more expensive unfortunately): this is the day and night with the SONY; the noise reducer acts perfectly. In addition, SONY do not call it a noise reduction (noise reduction) but a 'anulateur' noise (noise canceling): anything ... I totally recommend this.