The best source of what makes for a helpful review would certainly not be reviewers, or even dealers, it would be consumers of audio gear and consumers of reviews. Maybe its happened and I missed it, but I haven't seen any of the publications solicit in a serious way from paid subscribers what would be helpful in a review.
Most reviews that I read follow a loose pattern. A few meaningless introductory paragraphs meant to be clever. Then a usually detailed description of the products, its features, some measurements if we are lucky, nice photos, price, etc. Most reviewers do a good job of this and the information is very useful. Next we get subjective impressions. Some reviewers, I'll again tout Tom Martin, do a pretty good job of this by attempting a description that has some meat on the bones in terms of tone, soundstage, etc. Then, with a lot of reviews, you get a list of the songs the reviewer used-usually high tone stuff that is well beyond my plebeian tastes- never seen one that said ole George Jones never sounded better. The same florid language can be found over and over and, speaking only for me, represents empty literary calories. Then the inevitable "If you are in the market for a $______ amp, consider this one".
What's missing? A full disclosure of conflicts of interest so I can decide for myself if they matter. The kind of information Mike mentioned-practical stuff, small but useful features or annoyances that wouldn't be obvious at first blush. And at least comparisons with competitive products. Doesn't have to be subjective judgements about which is "better" but a comparison of features, sound quality, etc, between competing products. Reviews could tell us how specific products differ from one another without assigning rank.
Not universal truths-some reviewers provide more useful material than others and I'll again point to Martin's series on dacs. I think Soundstage does a good job and of course there are others. Maybe the publications should be explicit about the purpose of their reviews-is it just entertainment, as some suggest, or is it intended as a serious effort to aid subscribers in understanding the products?
