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Testing audiophile claims and myths - Page 14

post #196 of 3112

Can you describe your blind test protocol , since blind tests on IC cables are extremely rare this would be quite significant if it is verifiable, I still think it would be also very telling to objectively measure the cable differences, if there is a verifiable low pass effect on the cardas cable that is highly significant and suggests some serious mangling, what cardas cable is it by the way ?.

 

I have measured several cables of widely varying designs and never found any that significantly alter the FR, so your evidence could be very valuable !

 

Quote:
Originally Posted by DJGeorgeT View Post

yes, I have done a blind test and they sound different. The IC's sound different.

post #197 of 3112

sure, you thing.

 

I used my sansa fuze, the E5 FiiO amp, a pair of HD25 and ER4S and my colleage at work. Locked the volume on both sansa player and amp and sat a song on repeat.

 

Without looking, I had him swap the ICs and not tell me which one was swaped and record which one I thought sounded clearer and which one sounded darker. Then we compared our notes.

post #198 of 3112
Quote:
Originally Posted by DJGeorgeT View Post

sure, you thing.

 

I used my sansa fuze, the E5 FiiO amp, a pair of HD25 and ER4S and my colleage at work. Locked the volume on both sansa player and amp and sat a song on repeat.

 

Without looking, I had him swap the ICs and not tell me which one was swaped and record which one I thought sounded clearer and which one sounded darker. Then we compared our notes.



Thanks for the explanation. I'll be honest I am not sure I would regard that test as rigorous enough, how many trials did you do, were your comments consistent on each trial for each cable, also single blind tests are problematical as there are all sorts of unconscious cues you can pick up from the expeimenter, it does not mean that you cannot detect a difference but it is not terribly strong evidence either.

 

Seriously if you have the capability you could try recording samples of the analog outputs from both cables, then you could do a mathematical comparison of the FRs which would prove if the cardas did act as a filter.

post #199 of 3112

I can't remember exactly how many "rights" I got, but it was high up there in the 90% out of 30 to 40 tries and not all the tries flipping back and forth, but real tries like trying to trick me. Either I am a mind reader, extremely lucky or there are differences in the IC. Do the math on that probability...

post #200 of 3112

oh yeah, we used a  Y splitter as well. That one could have affected the sound, but I did not think so.

post #201 of 3112

and anyone who wants to try me out, here is the cardas cable:

http://www.headphone.com/accessories/cables/cardas-6-inch-mini-to-mini-cable.php

 

and the FiiO E5 comes with its cheap and free cable:

http://mp4nation.net/catalog/index.php?main_page=product_info&cPath=9_45&products_id=261

 

and you should have an HD25, ER4S, fuze, etc.

 

Do those "rigurous" tests for me nick_charles  since you are so interested.

post #202 of 3112
Quote:
Originally Posted by Shike View Post

I believed that by "as intended", you implied that the whole chain from the source to the auditor should be "wire with gain".

 

That's exactly what I'm saying - that is the only way to guarantee accurate reproduction of the signal.

 

That's what I mean too, the reproduction chain should be wire wire gain, especially considering that abrupt peak and dips are difficult to correct, except that I add digital room correction and EQ in the chain.

 

That's what I disagreed with, to me the ideal reproduction system would take into account room acoustics and equal loudness contour. Room acoustic correction is a given I think, but equalising for loudness is good IMHO, you don't want the lowest notes froom a piano or a double bass to disappear whan listening at low volumes, would you?

 

The problem with adjusting for loudness curves is they vary based on volume anyway, so calibrating for 80dB isn't the same as say 85dB.  Furthermore, your brain, as I said, is used to these contours day in and day out.  Trying to correct for them may change how your brain adds to the signal. 

 

I would hazard a guess and say that the tests that were used to create the equal loudness contours were subjective and thus already took into account "in-brain correction". From a more personal pov, I feel that the distribution between HF, LF and the mids change depending on the volume I listen to, hence why I think that the brain, or at last mine, doesn't correct enough. I would say that a proper signal correct is very time consuming.

 

Anyway, when listening at low volumes, I feel that adding a little bass and treble boost makes music sound more natural, maybe your ears require less compensation, or your brain compensates better than mine, but we are getting in a matter of preference, so unless there has been a serious study about it, we should let the matter drop.

 

"By the way, the AKG K601 which is a 'flat' pair of headphones according to you (I don't know, I didn't bother to check), is probably flat once the free field diffusion curve is applied, which means it's does not have a flat response.

 

Possibly, would have to check with headroom regarding which equalization methods they use.  I know they try to remove HRTF via equalization on their dummy heads - it was my understanding this would leave transducer response considering average head coupling (which is necessary).

 

My understanding is that "neutral" headphones are designed to sound flat with HRTF taken into account, thus the transducer basic FR is not flat, but the measured signal with a dummy head (which cancels the HRTF) should be flat. I have doubts about the headroom measures above 10k, it could be a limitation of their measuring equipment as a lot of headphones don't sound like they they have plus or minus 10 dB peaks or dips.

 

Responses in blue.

post #203 of 3112

@khaos974

 

Checked Tyll's thread about building a lab, and it seems he measured for headroom using DF, so pretty close guess on the measurements.  You'd be right then, the K601 isn't flat at transducer level . . . hrm, not sure what I think.  I'd like to get a flat headphone from every school of thought now to see how they compare . . .

 

As for their above 10Khz measurement - you're right, they aren't that accurate going up that high.  It's the same reason the DT48 only guarantees flat measurements on certain ranges.  It probably has to do with reflections and other issues thanks to the psuedo ear on the dummy.

post #204 of 3112
Thread Starter 

Khaos and Shike, with all due respect you are miles off topic, why not PM each other?

 

DJGeorgeT, would you do your test again, keep your score and follow Nick_Charles protocols as closely as possible so we can add you test to the thread. Thanks.

post #205 of 3112



 

Quote:
Originally Posted by DJGeorgeT View Post

I can't remember exactly how many "rights" I got, but it was high up there in the 90% out of 30 to 40 tries and not all the tries flipping back and forth, but real tries like trying to trick me. Either I am a mind reader, extremely lucky or there are differences in the IC. Do the math on that probability...





Quote:
Originally Posted by DJGeorgeT View Post

oh yeah, we used a  Y splitter as well. That one could have affected the sound, but I did not think so.





Quote:
Originally Posted by DJGeorgeT View Post

and anyone who wants to try me out, here is the cardas cable:

http://www.headphone.com/accessories/cables/cardas-6-inch-mini-to-mini-cable.php

 

and the FiiO E5 comes with its cheap and free cable:

http://mp4nation.net/catalog/index.php?main_page=product_info&cPath=9_45&products_id=261

 

and you should have an HD25, ER4S, fuze, etc.

 

Do those "rigurous" tests for me nick_charles  since you are so interested.


Please do not feel put-upon. Whenever a big claim such as yours is made it is rational to ask for strong evidence, you omitted much of the relevant details until after I questioned your protocol. The claim that ordinary analog cables are audibly different has never been supported by good evidence that is why when such claims perennially emerge it is important to investigate the evidence, it was not a personal attack.

 

As for the stats it is impossible to do them without real numbers and preferably the "lab" notes since there are order effects and a set of trials not properly randomized will show the bias that we have to hear different even when no difference is made.

 

However I can do something different and better. I can get the cardas cable and the FiiO with freebie and I have several other mini to mini cables ranging from very thin to 79 strand speaker cable gauge and measure them in circuit with a musical signal so as to show the FR of each, any low pass on the Cardas will be quite obvious.

 

 

EDIT: Cardas cable and E5 ordered - will update when received and tested.

 


 


Edited by nick_charles - 10/14/10 at 12:55pm
post #206 of 3112

Very interesting thread. I wonder if any of these A/B tests had included an extra random test element (like simply flipping a coin, heads = A & tails = B) and see if that was more accurate than the listening panel.

 

Also, I seem to recall a member here who has a registered blind girlfriend (can't find the trhead) and her hearing is so acute she could tell that the vocalist wasn't recorded at the same time as the rest of the band. Would she be able to discern differences in equipment?

post #207 of 3112
Thread Starter 
Quote:
Originally Posted by spookygonk View Post

Very interesting thread. I wonder if any of these A/B tests had included an extra random test element (like simply flipping a coin, heads = A & tails = B) and see if that was more accurate than the listening panel.

 

Also, I seem to recall a member here who has a registered blind girlfriend (can't find the trhead) and her hearing is so acute she could tell that the vocalist wasn't recorded at the same time as the rest of the band. Would she be able to discern differences in equipment?


All of them should involved flipping a coin, but if you get 6 heads in a row you may need to doctor things slightly. Perfectly random would be 50%, but since a difference is being claimed that is often night and day, then a 90% pass is reasonable. Less than 90% and you may still have a difference, but one that is very hard to detect. But, and the reason for putting this together, we need more tests, amny more to really conclude whether audiophile claims are really myths or not. So far though, it is not looking good for those who say cables do make a difference. Sadly, that is hampered by some who claim great success in blind tests, but are not forthcoming with their protocols and full results.

post #208 of 3112
Quote:
Originally Posted by nick_charles View Post

 

Cardas cable and E5 ordered - will update when received and tested.

 

So what do you think the reaction will be in "No Science Allowed" forum if nick_charles finds an IC that really does sound different?

post #209 of 3112

don't forget the er4s  or hd25

post #210 of 3112
Thread Starter 
Quote:
Originally Posted by maverickronin View Post

 

So what do you think the reaction will be in "No Science Allowed" forum if nick_charles finds an IC that really does sound different?



Hopefully positive and followed up by lots of similar tests. I suspect that instead there will be lots of gloating and a refusal to do anymore tests.

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