The current discussion on headphone reviewing throws up and interesting question, do you think that you need knowledge to be classed as a good reviewer that someone will take seriously, or can you just be an keen hobbyist describing what he feels. I mean you could be a musician, years and years testing differing equipment and then describe the best you can what you hear, you may not fully understand why and how it all works but would this invalidate your review? Or do you need technical knowledge to explain what you hear and why it is doing what you hear?

I've read many a good review that is not technical, and I've read technical reviews that baffle, so which way is it?

In order to reliably report and review the technical performance of technical equipment a person needs to be at least technically competent and, preferably, a technical expert. This applies to all technical equipment and follows from the need to know what is going on in order to be independent of claims from both the manufacturer and, particularly for home audio, the industry as a whole.

Audiophile reviews and most discussions in audiophile forums are not about technical performance which many audiophiles find uninteresting but about "audiophile performance" which is something quite different. Unlike technical performance which is straightforward to independently quantify and verify audiophile performance is not. Unlike technical performance which is the same for everybody, audiophile performance clearly varies from audiophile to audiophile. Some of the things that add to or subtract from audiophile performance are a function of the equipment itself (looks, technical performance) but many, as is typical of luxury goods, are not and are shaped by marketing and the audiophile's environment and history.

clearly varies from audiophile to audiophile

If one bears that in my I don't see a problem, happily I think most know this apart from what hi-fi? readership.

I'm with Hg on this all the way.

As he said, you don't have to be an out-and-out expert, but you do have to have technicaly savvy, else you'll be influenced by catchphrases and manufacturer sales lobbies.

Lets twist it a little and ask, what percentage of reviewers have technical knowledge?

How can anyone answer that? Who knows all the reviewers? Especially now, in the days of Internet, when everybody think they can do reviews?

Pitifully few would be my answer.

Hg, walk a little softer here. But you can keep the stick.

"Magical" properties are the explanations of those who do not know technology. I can demonstrate a simple test - I'll use a given op amp, backed up by a driver and output stage in discrete technology, to eliminate even the question of the op amp's current delivery capabilities, which are an issue far more often than is suspected. Very plain, off-the-shelf components, for example, BC 546/556 B for drivers and say BD 139/140 for the output stage, as vanilla as it gets.

We can then listen to it and measure it all at will. Then, I'll swap the input and NFB circuit resistors from no name 0.6W 1% metal film to a well known company, reputed for their resistors. The sound WILL be a little different, not much, just at the threshold of audibility, but picked out right on blind test at least 8/10 times, more likely even 9/10, which I hope you'll agree is statistically very significant.

Do the standard static and dynamic tests and you'll find them to be identical to the previous set. So, you have exactly the same measurements, but a slightly different sound?

Would you agree that most audiophiles would attribute this to whatever magic they happen to believe in?

Back at the lab, we'd sit down and do some non-standard tests, which anybody can do, but are never done, to the best of my knolwedge, and sure enough, in the end, we'd find some differences in those resistors which caused the difference in sound. Lower inductance, better thermal behavior, whatever. In the end, it would all point out to manufacturing practices, tolerances and materials used.

But, who, and where, ever went that far in a publication, paper or electronic? Whoever bothered to explain to the people the root of these differences? Especially in the given environment, which as you so aptly pointed out, is hell bent on getting as many advertisers as possible? Who is even willing to do things like that these days? And for whom, a bunch of metrosexuals, pretending to hear the grass growing and the paint drying?

You see my point? When examined thoroughly enough, you will always track down the differences, it's merely a question of how deep are you allowed to dig. What seems like magic always has a rational explanation. A simple example: a friend and I made the same project, each as he wanted to. Mine ended sounding better and measuring significantly better than his for, basically, two reasons: 1) he used Motorola's MJE 340/350 in his cascode stages, while I used the far more sophisticated but harder to come by Siemens BF 720/721, and 2) he used Motorola's MJ 15024/25 output devices, while I used Motorola's MJ21193/94 devices. Same manufacturer, same power rating, on the surface, identical transistors, but look more carefully at their Data Sheets and you will begin to notice small differences, which will start to add up. So my compensation was gentler than his, and we both had exactly the same number and type of components, only of different value, I simply didn't need the values he had to use. But, looking at the printed circuit boards from the outside - exactly the same.

You would examine them closely and find the differences, then would sit back and reason it out. A layman would at best count them and visually compare them, and to him, they would BE the same. And the difference in sound would be "magic".

I don't get this term 'magic' I don't know many who think or speak like this, the only rime I see it is in 'cough'' cough' reviews.

I think most of us know it's just down to component changes or values etc, nothing magic or mystical about that, I think the term 'magic' is used very lightly.

Here is what my friend Peter from Germany has wrote regarding reviews:

Peter Steinfadt
The situation in Germany: Nobody believes in reviews as readers know, that 97,7% are paid for (with ads). The role of reviews in general is not important anymore. For me as a distributor reviews are just "nice to have" but not essential. Recommendations and own listening experiences are everything. The times are over, where a "good review" showed some results in sales figures. I guess, that some "big names" in our biz destroyed a lot: review on p.34-36, ad of the same product on p.38... I talk about print mags, the situation might be different with online publications. Good experiences and fair/competent partnership: 6moons. Srajan explained all weaknesses and strengths of my products that have been reviewed. And I could agree to all statements.

I agree with his finding that getting a good review wont guarantee a spike is sales, I've had a few reviews and noticed no changes, I find the best method is mouth to mouth, or even forum hype.

Adam, you may not have been in that situation, but I have, far too many times.

Somebody makes a claim that by changing some resistors for same value but another brand has "opened up" his system and "let the sunshine in". Even at surface value, this is a ridiculously overblown statement; I myself said in another post that this CAN bring about differences, but they are minor, at best at the very threshold of audibility.

Another guy told me that when he changed the internal van den Hul wiring of my filter with cable from Cardas, which costs around 6 or 7 times what my cable costs, he immediately perceived a "trenedous improvement in the sound of he entire system". At least in his case, I know for a fact that this is not true because we tried that cable ourselves and found that if it made any difference at all, it was below the threshold of our audiability.

All this "revealing", "magic" and so forth is wishful thinking and perception that something costing much more MUST be better by default. It's the placebo effect, pure and simple, but it's running rampant in the so called audiophile circles. People are making wildly exaggerated claims which have nothing to do with reality.

And sometimes, the fates can make cruel twists on such people. One locally highly respected audiophile contracted some bug or whatever and had to go and have his ears tested. It seems his doctor thought this serious enough for his overall hearing that he ordered a complete test of his hearing, including sensitivity and frequency response mapping. And it turned out that the man had some very serious issues with his hearing, because it was a wildly broken up line across the hearing bandwidth, dropping sharply after around 12 kHz, with deviations of +4, -5 dB relative to zero across the band. That sort of ruined his reputation.

You may not see much of it, but as a manufacturer, I sure do. So many people know much better than me how I should have made whatever, I sometimes wonder why I bother at all. But, my friend Milan Karan comes to rescue in such times of darkness - he has a great way of dealing with such armchair scientists. He tells them - look, I did it the way I thought was best, and when you come back and bring me something, anything, you designed and made with your two handsa, THEN we'll discuss design policies at any lengthe you care for.

Believe me, Adam, ever since I adopted his priciple, I do sleep much better.

I have to say I find hg's terminology highly offensive. It seems as though his mastery over measurement is supreme and all the answers are in his mesasurements alone. Any experiences which differ from his measurements appear to be figments of my imagination; I am therefore deluded, either by the magnificent marketing I haven't read or through the (similarly non-existent) voodoo mojo of the rep I didn't meetwhen he delivered the latest gadget.

Hg, I find your attitude utterly objectionable. I am so very glad that real scientists and engineers are nothing like you. In my experience they're thoroughly nice people and, oddly enough, they're far more accepting of others' experiences than you ever will be.

No, because your argument brooks no question.

What r u hg, if you are not an audiophile, what do you class ur self as?