Blind test investigations...

[cortisolman]

After doing some reading on the Eliot Sound Products web page, and consequently visiting this, http://www.provide.net/~djcarlst/abx.htm, hideously old site I have realized that trusting results from a DBT/ABX test can be useless. While I remain "scientific" in my approach to audio, I think a lot of these tests are just as biased as "normal" testing.
They tend to simplify the testing process, down to a level where there doesn't seem to be enough time to "get to know" the products. And hey, if they think cables don't sound different, and test assuming that, how is that any different from people who do think they sound different testing. There is still a bias!

It's been six months since the last punch up in here, but that's not what I'm trying to get. I'm just hoping to get some calm, reasonable responses so that people can thrash out their ideas.

[cortisolman]

A good comparison I thought of was if you are comparing two similar road bikes, for roughly the same price.

If you go blind testing (ignore the difficulties...:p), switching back and forth on rollers, you never learn the feel of the bike. They will feel the same, because they are similar. BUT if you take them out on a 5 hour bike ride through the hills, then you can appreciate the subtle difference in speed, control, comfort etc.
If you did a five hour test blind, (uh... even more difficult) then you could remove bias that brands and looks can have on your opinion, and possibly get a better test outcome. However, in the audio world, week long blind tests are impractical and inconvenient. It would take a very dedicated team to do this.

So... each to their own, as long as it makes you happy, but I just thought I'd spin up some of my ideas.

[Ernie]

Jake, you've chosen a good topic to monologue. It's worthy of a blog. ;)

[Antipodes]

I have had to confront this problem in auditioning small changes in interconnect designs. Here is how I see it.

The sound that arrives at our ears, and what we think we hear, are not the same. Our brain works hard to make sense out of what arrives at the ear to make distinctions between the direct sound and first reflections, and many forms of time based distortion in the system or in the room. Playing music on one system and then changing one piece of gear in it to play the same music again, will have the subconscious of your brain trying to make them appear to sound the same, not different. In an ABX test where the listener is concentrating more, the brain will work even harder at this. Our brains work less hard when listening in a more relaxed mode and over a longer period as it is too fatiguing for the brain to work the way it does in a double blind test. You get a much greater sense of how the sound of two components differ if you listen to the music, not the system and over a longer period. The longer period adds problems with aural memory.

Therefore I find the best way to do tests is to spend long periods with the alternatives and over these periods I begin to identify the traits that distinguish them. I can then listen in shorter bursts to focus on identifying the tell-tale clues. Then I conduct double blind tests - once I know what I am listening for, to check that the clues I have identified are able to be reliably picked out.

Double blind tests are only useful after you have a lot of familiarity with the two things being compared and after you have identified the tell-tale traits of each. Double blind tests with unfamiliar components rarely shows differences that will emerge over a longer period.

[bellapl1]

Wow. That must be the most sensible info on ABX testing I have ever seen.

Especially the part about our brain trying to make differences sound the same. It just makes sense.

[T110]

DBT=double blind testing. Please enlighten me on ABX. Also a brief description of each. I think I know what DBT is but having lost interest in reading Hi-Fi mags since the encroachment of home cinema I cant be sure. Thanks.



OK I just googled the ABX website. That covers that. Would still appreciate a brief description of Double Blind Testing just to confirm my own understanding. Thanks.

[aarond]

. Would still appreciate a brief description of Double Blind Testing just to confirm my own understanding. Thanks.

Boring! > DBT/ABX

Quick cut and paste. :)

[T110]

Boring! > DBT/ABX

Quick cut and paste. :)
Very informative. Thanks cobber. By the way, how's that analogue set up treating you? I'm rediscovering old vinyl that I haven't played for years because it didn't sound so good. Now I'm saying to myself "shit, is that how it's supposed to sound?"

[aarond]

Hmmmm, sorry about that - no offence was intended, just my warped sense of humour.

I think that Antipodes has summed it up very well, it is the getting used to something then removing it that really points out the differences, IMHO.

As for the analogue set up, well I would have to say that it isn't being used much because it is trounced in every respect by the Marantz SA11 / Nordost cabling digital playback chain. In terms of value for money, the Rega is better than CD at its price point, but the SA11 is in another league being up at $6000 new.

Nothing to do with surface noise, which surprised me by not being an issue. the CD player just has much better dynamics, bass, soundstage, depth, detail, tone and overall 'rightness'.

On a good lp, female vocals get a bit closer, but piano quite frankly is quite unlistenable - it sounds 'slurry'.

I'm considering upgrades to the TT as in PSU / platter, but not sure whether it is worth throwing more $$ at.

At the end of the day, it is reassuring that the CD player is much better, considering the difference in investments!

[cortisolman]

Antipodes, that was a REALLY good take on it, I think I'll remember for future. Thanks.
Out of curiosity, have you done this DBT method using fresh cable and then ones you've burnt in? Was it easy to pick the difference?

[aarond]

Sorry for the thread crap, cortisolman. :o

I went back to cut and paste my off topic musings it into another thread, but I was too late to be able to edit it.

[cortisolman]

Forget about it, happens all the time here eh. Actually I was quite interested to read that, I've often thought about delving into vinyl but obviously its going to be way too expensive to get what I want, plus CDs are just so convenient.

T110 it's basically just testing where you don't know which component you're listening to, which you are probably aware of. It's supposed to remove bias of your sight on your hearing. For example, huge speakers might sound more powerful than they really are at first impression. Its a medicinal approach to audio. Works well for testing new medicine, but does it work well for audio?

[T110]

Forget about it, happens all the time here eh. Actually I was quite interested to read that, I've often thought about delving into vinyl but obviously its going to be way too expensive to get what I want, plus CDs are just so convenient.

T110 it's basically just testing where you don't know which component you're listening to, which you are probably aware of. It's supposed to remove bias of your sight on your hearing. For example, huge speakers might sound more powerful than they really are at first impression. Its a medicinal approach to audio. Works well for testing new medicine, but does it work well for audio?
Pretty much as I thought then. Thanks.:)

[Antipodes]

I forgot about this thread.

Yes I have done DBT tests with new and unburned versus burned in cables and the differences are pretty clear. The unburned cables sound less natural and smooth with an aggressive top end and a waffly low end. We even did some tests where I sent out an uncooked and a cooked cable to several Audioenzers. Noone failed to hear a difference and everyone preferred the cooked cable - and the cables were marked meaninglessly so that it wasn't possible to guess which was which. It wasn't at all scientific, but the consistency of the results was very notable.

Interestingly I haven't been able to measure any difference in LCR between raw and cooked cables. The current theory I am working on is that eddy currents are more severe in a raw cable than a cooked cable, which doesn't affect a gross measurement of LCR but which has subtle impacts on timing. In the cooked cable conductive patterning develops that reduces eddy currents. Therefore the raw cable will sound less natural to our ears. The two waveforms must be different, but I haven't yet figured how to measure that accurately enough to prove it.

[cortisolman]

That's really interesting. I've never been a fan of the statement saying cable burn in makes a difference, mainly due to the fact that there was no scientific basis (YET) and I feelthat most people listening a few hours a night, a few times a week, would have absolutely no memory of such subtle changes.
Please keep me informed, and I'd be more than happy to take part in any future tests!

[bazza hallward]

That's really interesting. I've never been a fan of the statement saying cable burn in makes a difference, mainly due to the fact that there was no scientific basis (YET) and I feelthat most people listening a few hours a night, a few times a week, would have absolutely no memory of such subtle changes.
Please keep me informed, and I'd be more than happy to take part in any future tests!


I have found a couple of articles about scientific tests on cable burn in and changes over time. Only via google scholar (so not very comprehensive), and they weren't about hi fi cables. Although that could give it more legitimacy. The experiments measured changes in electrical properties in cables due to burn in, and how that affected measurements in precision equipment in experiments.

[mycenius]

I have no idea what you are talking about Bazza, but I thought I'd do the honourable thing and take you off the heroic "last post" for this section! ;)

...after all, it's been almost 7 months! :eek:

[cloth_ears]

That's very noble of you John.

[cloth_ears]

Doh.. now I'm last:o

[mycenius]

That's okay buddy, since I've been gone awhile, I'll fall on my Sword... AGAIN!!! :eek: :p

:D