As far as I am concerned HIFI magazines have a duty to be objective. Sometimes I doubt their sincerity. All sorts of claims are made about the reviewers' abilities to notice "night and day" differences between reproduction equipment and digital music file formats -24/96 and 16/44.1 etc.
With regard to equipment, amplifiers should sound very similar,all other things being equal, if they are of HIFI quality: this just stands to reason. When the magazines provide measurement data amplifiers show similar characteristics from a measurement point of view. When listening tests are made of amplifiers there is never any attempt to implement double blind testing. The reader is offered no form of evidence as to which is the better amplifier.
The same applies to all other forms of equipment CD players, Turntables, Cartridges, Cables, Mains filters etc. There is never any evidence. It is egregious that before and after measurements are not made in the case of cables or mains filters. The only evidence seems to be that expensive is good and the more expensive the better.
Similarly for digital file formats, the HIFI magazine reviewers always claim that in their listening tests 24/96, 24/192 or DSD files sound better than 16/44.1. There is no evidence that anyone can regularly tell the difference, all other things being equal, between such files. There is not much evidence that anyone can hear the difference between a 320 kbps MP3 digital file and a 24/96 digital file. Still the HIFI magazines persist in making claims that they can hear night and day differences. What makes their hearing so special? If their hearing is so special let them prove it by submitting themselves to scientific testing. I doubt that that they ever will.
HIFI forums have no such duty to be objective but most of them repeat the same errors. They will traduce equipment that they do not like and half the time I suspect that they have not heard the kit they are criticising. Most of the opinions on most of the forums are bunkum.
This one is a notable exception as it makes an attempt to be objective and scientific and I think it succeeds.
http://www.head-fi.org/t/486598/testing-audiophile-claims-and-myths
There must be others and it is worth finding them.
How about this?
http://www.harbeth.co.uk/usergroup/showthread.php?1663-Double-Blind-Testing-(DBT)-and-a-refutation-of-the-A-B-listening-experience&p=19876
What is Joe Public to do when buying HIFI? Trust his own ears - that is all but buyer beware.
