Axiom Home Page Forums General Discussion Advice from Axiom Owners Hybrid amps with Axiom M60v2s

In a true double blind test there would be no information given to participants nor there would be any interaction between the experimenter and participants. The goal is to create an unbiased testing environment as possible to ensure accurate results/minimize error/bias or any other anomalies.

From Axiom's page About the Research:

Training is important, otherwise they could have classified good speakers "bad" and bad speakers "good"... Hm... how was first determined which of the speakers were supposed to be the good ones and which the bad ones?

I understand CV point now. Both are valid IMO . Say one study with 10 random joes/jills as participants vs 10 industry professionals in the other for example. What would the results show then?

I suppose, as with many audio tests, one needs a reference point of some kind. Some people prefer bass heavy music and therefore say a "fat" sounding speaker is "normal" or perhaps someone who prefers classical type music might prefer hearing a more "forward" or detailed sound ect. I guess if the test is done with enough participants, either way there should be an overall census on what sounds "right".
I tend to discount any review or opinion that is too over-the-top or one that is very underwhelming.

but most people measure straight up frequency response into a machine load and THD without any understanding of why this doesn't translate 100% into what we hear when it's driving a real speaker.

I can tell you that I preferred my brother-in-laws Jolida 302 tube amp with my Axiom M60s to my Denon 1804 solid state. I borrowed the tube amp for about three months. I rarely listen to music louder than about 85-90 decibels, so it is not a matter of pushing either amp to the point of clipping. The Jolida seemed to give the music more depth and fullness. I did not do any double blind tests so discredit my findings if you wish. Upon going back to the solid state amp, I found that preferred the tube sound. The only way that you will know whether you like the tube sound is to listen to one yourself.

Hi CV, Edmondwolfman, and all,

Interesting discussion, and I think a few comments are appropriate. Until recently, there has been very little controlled double-blind testing of trained versus untrained listeners in loudspeaker listening tests. As many regulars on the forums know, I participated for years doing double-blind listening tests of various speakers (for magazines I was editor of) at the National Research Council in Ottawa, Canada. Indeed there was a training period for all regular members of the listening panel so we could quickly zero in on such speaker colorations as "fat" bass and other anomalies.

In recent years, however, acoustical scientist Sean Olive (who was finishing his graduate work at the NRC under Floyd Toole when I was on various listening panels) conducted an elaborate study using 300 untrained and trained listeners at the Harman acoustical facility, which is a more elaborate setup than the NRC's listening room. What's fascinating about the results is that essentially the untrained listeners' ratings of good and bad (accurate and non-linear or inaccurate speakers) nicely tracked the ratings of the trained listeners. The major difference was that the trained listeners gave lower scores overall than the untrained listeners.

You can read the study in greater detail at Sean Olive's blogspot and download the study for free here:

http://www.aes.org/e-lib/download.cfm?ID=12206&name=harman

I'd also point out that tube amplifiers do not necessarily sound different from solid-state amplifiers (except when pushed beyond their output limits into distortion). Tube amplifiers can be well designed for linear smooth frequency response and low distortion. In one double-blind test of amplifiers at the NRC in which I participated, there was a large tube MacIntosh amplifier that measured flat and had low distortion. No-one on the panel was able to distinguish it from a number of other solid-state amplifiers during the tests.

Regards,

Alan

Thanks for that info Alan, that is a very interesting study.

Thanks, Alan! I'll have to read it later, but I look forward to it.