Blind test: we have a volunteer!!!

[bboris77]

I think we may have missed a major potential issue here - who will administer the Breathanalyzer test?


P.S. On a serious note, this whole thing has to be done in good faith despite all the previous skirmishes. If people are going to assume that @GoldenOne will try and cheat the test, they will eventually convince themselves that he did, no matter what.

 

[voodooless]

I think we may have missed a major potential issue here - who will administer the Breathanalyzer test?

I think nobody. I'd say that any kind of performance-enhancing drug is allowed as long as it remains within the legal framework of the country

 

[GoldenOne]

The A90 is a poor choice to use as a comparison. Not a poor amp but not the wisest choice for design reasons as both use the exact same output device (TPA) and seem to let most of the gain be handled by another opamp. Also both seem to use the same 'trickery' to get a low output R.
Chances are that the pure resistive load of the Susvara will be a very easy load when some 'trickery' is used to prevent the TPA from oscillating on complex loads. The Susvara (nor HE1000, nor Arya) are anything but a complex load.

When there really are audible differences between amps I would expect them to be in the business end (output stage) combined with loads.
The PCB design of Schiit would have to be really Schiit to differ that much, which I don't think it is, but given the 20dB difference in crosstalk for 32ohm between SE and balanced it does raise some concern about the common/return path. Not that -70dB crosstalk is audible but just an observation.

I was about to comment about the Atom and AHB2 to be similar in performance yet not the Magnius.

Atom is SE in and not balanced out. This would require SE out for Magnius and SE inputs.

IMO either compare balanced or SE and not SE to balanced.
SE out on Magnius (acc. to specs) I would consider bordering on audible. High Gain, SE Output: Less than -72dB at 2V RMS into 32 ohms, CCIF

More thought needs to go in amp selection. You might not be doing yourself a favor comparing to very similar devices if you want $1000.- to go to charity

That's a good point. Perhaps singxer sa-1 vs magnius might be a more ideal comparison?

 

[Raindog123]

Only other issue is trying to find a magnius in the UK. Unfortunately the uk/EU distributor for schiit is... Well schiit at actually keeping stock of anything. And shipping from the US is ~£40 extra.

If it helps, I'll gladly chip-in a $100 to cover the shipping...

 

[aandres_gm]

I'd really like a such test done with DACs. That would be fun.

 

[Raindog123]

@amirm @GoldenOne

Guys, and it's a long shot but... My daughter got accepted to KCL (and to a couple of US schools here), so we're heading to London the first week of July. To scout the school, for her final decision... And per current covid rules, we'll have to sit in quarantine for quite a few days, but if timing works I'll gladly be Amir's (and ASR's) proxy. And it will be pleasure to meet the @GoldenOne...

(But as the whole world is waiting, if everything is setup sooner I am sure we can still find local esteemed gentlemen to oversee the test.)

 

[magicscreen]

If he fails, it just means he's susceptible to placebo, as all humans are.

No, it just means the blind test is a wrong method.
You cannot use your fallible ears+brain to prove that your ears+brain is fallible.

 

[MrPeabody]

I can report tomorrow whether I think the atom sounds different to the stuff I have here. And as soon as the Magnius arrives I'll confirm if it sounds different to me to that as well.

And yes. Some amps do sound either indistinguishable or incredibly similar to the point where I'm sure i wouldn't be able to reliably tell them apart.

I never claimed that EVERYTHING sounds different and that's also not what we're looking to test.

Wow. You have just made it apparent that you are seriously confused. You seem to think that all you need to prove, to be shown correct, is that you can hear a difference between the Schiit amp that you criticized and some of the other funky-sounding amps in your collection. What would this prove? Only that some of the amps in your collection sound funky, and that this is why you like them, and that the true reason you criticized the Schiit amp is that it doesn't have the funky sound that you like. You might as well go ahead and admit that you prefer amplifiers that distort the sound in a certain way and that you disapprove of amplifiers that do not distort the sound the way that you like. So long as the other amp that Amir wants you to use is not practically identical in design and construction to the Schiit amp, you need to give Amir full control over the "other" amp. Otherwise, you will be admitting in essence that you disliked the Schiit amp only because it didn't exhibit the funky distortion that you like, so you may as well admit to this now and save yourself more embarrassment later.

What I just wrote is pretty blunt, but it needed to be blunt because what you wrote suggests that you believe that all you should have to prove is that you can hear a difference between the Schiit and some other amps in your collection. You need to make it as clear as you possibly can that this is not what you believe and that you understand that you need to be able to demonstrate that you can tell the Schiit amp apart from other amps that are known to be extremely accurate, not just the funky-sounding amps in your collection.

 

[PierreV]

Wow. You have just made it apparent that you are seriously confused.

A bit of positivity wouldn't hurt.

My rational side would like to see Goldenone fail but my emotional side is beginning to root for the underdog because of the armchair abuse he has to endure.

The guy has accepted almost everything that has been thrown at him so far. If he passes the test, he'll do better statistically than what the vast majority of actual papers produced in the field do.

 

[MDT]

If he can tell the difference, the interesting thing is then to find out what it is that is audibly different. Obviously there's no point comparing two amps where one is not *measurably transparent.

*To the extent we believe they should be transparent.

I believe everything can be measured, so two transparent amps should be indistinguishable. However, it would be interesting if he passes the test, to then try to find what it is made the difference.

 

[MrPeabody]

A bit of positivity wouldn't hurt.

My rational side would like to see Goldenone fail but my emotional side is beginning to root for the underdog because of the armchair abuse he has to endure.

The guy has accepted almost everything that has been thrown at him so far. If he passes the test, he'll do better statistically than what the vast majority of actual papers produced in the field do.

What you perceive as positivity or negativity is totally irrelevant. Goldenone wrote something that clearly suggests that he fundamentally misunderstands the premise of the experiment in which he is a the key player. It is not appropriate for this to continue further if he continues to harbor the misconception that all he needs to prove is that he can hear a difference between the Schiit amp he criticized and the other funky-sounding amps in his collection. This is a simple point, and a very important point. It is not helpful or productive for anyone to write anything that obfuscates or diminishes this point.

 

[Chocomel]

Wow. You have just made it apparent that you are seriously confused. You seem to think that all you need to prove, to be shown correct, is that you can hear a difference between the Schiit amp that you criticized and some of the other funky-sounding amps in your collection. What would this prove? Only that some of the amps in your collection sound funky, and that this is why you like them, and that the true reason you criticized the Schiit amp is that it doesn't have the funky sound that you like. You might as well go ahead and admit that you prefer amplifiers that distort the sound in a certain way and that you disapprove of amplifiers that do not distort the sound the way that you like. So long as the other amp that Amir wants you to use is not practically identical in design and construction to the Schiit amp, you need to give Amir full control over the "other" amp. Otherwise, you will be admitting in essence that you disliked the Schiit amp only because it didn't exhibit the funky distortion that you like, so you may as well admit to this now and save yourself more embarrassment later.

What I just wrote is pretty blunt, but it needed to be blunt because what you wrote suggests that you believe that all you should have to prove is that you can hear a difference between the Schiit and some other amps in your collection. You need to make it as clear as you possibly can that this is not what you believe and that you understand that you need to be able to demonstrate that you can tell the Schiit amp apart from other amps that are known to be extremely accurate, not just the funky-sounding amps in your collection.

All the gear he offered for testing is well measuring, well designed stuff. It's not like he's offering to test a magnius vs a 200ohm OI OTL tube amp with a focal clear.

 

[Thomas_A]

These DBT challenges reminds me of one test some 20 years ago (?) that we made in Sweden and one guy from the USA should travel to Sweden and attend as a controller. This was related to a discussion on the forum "Audioreview" We waited one hour or so but he never showed up or answered telephone. Still remember how painfully hard it was to listen to drumsticks hitting the edge of the drum on repeat and high volume. 11/13 correct was the end result.

 

[Ron Texas]

Experimental brain surgery, we have a volunteer...

 

[solderdude]

That's a good point. Perhaps singxer sa-1 vs magnius might be a more ideal comparison?

The Singxer should be a better comparison. Both have higher distortion SE and excellent performance otherwise in balanced.
Discrete, partly class A output vs TPA6120A would be a better comparison.

In case you have it (I assume you do) you could setup everything compared to the A90 and see if you can spot the difference in an actual blind test.

Speaker amps with actual (difficult) loads would be a lot easier to AB.
60ohm almost purely resistive is a walk in the park for almost any design that measures well at 32ohm and 300ohm.

Here's another test you can do when checking amps to spot the difference and to setup the system so the output is equally loud.
Play music through both amps at the same time. Connect the headphone between the + out of the balanced amp and the + out of the other amp.
Load both amps with another headphone like you would normally do.
When amplitude is properly matched the headphone between the 2 + outputs should be totally silent.
I would recommend a higher imp. headphone for this, preferably closed.
You can also record the difference while at it and analyze the crap out of it using music and actual loads.
You can also directly hear the differences between both amps. If that sounds 'normal' but very soft the amps perform the same, the waveform is the same and you cannot possibly pass any AB test thrown at it.

 

[SoundAndMotion]

@MrPeabody Unless you've put something on the line (money, equipment, time), your opinion may be useful, even valued, but you have no say in the choice of amp. Amir does not need your protection. He (and @GoldenOne !!) need to both agree to the conditions (including choice of second amp). Does GoldenOne have a "collection of funky-sounding amps"? I was not aware, but I haven't read all the posts in both threads.

 

[Iving]

@MrPeabody Unless you've put something on the line (money, equipment, time), your opinion may be useful, even valued, but you have no say in the choice of amp. Amir does not need your protection. He (and @GoldenOne !!) need to both agree to the conditions (including choice of second amp). Does GoldenOne have a "collection of funky-sounding amps"? I was not aware, but I haven't read all the posts in both threads.

see also Peabody p.8!
https://www.audiosciencereview.com/...nd-test-we-have-a-volunteer.23857/post-804230

 

[Blaspheme]

No, it just means the blind test is a wrong method.
You cannot use your fallible ears+brain to prove that your ears+brain is fallible.

Nice wordplay. ABX has other problems.

At least, reading this thread, next time someone tells me that not doing same routinely is unacceptable because it's "trivially easy", I'll know they are full of it.

 

[Jinjuku]

Now there is an idea. I could record the output of Magnius and whatever else he said sounds better and have him go through this checkpoint first. Good thinking!

He had so many issues with Magnius sound that he better be able to hear it in such a test.

I would want anyone doing this to do a 320kbps MP3 to 24/192 PCM and if they can reliably pass that then move on.

 

[GaryH]

I would want anyone doing this to do a 320kbps MP3 to 24/192 PCM and if they can reliably pass that then move on.

What makes you think the specific ability to recognize lossy compression artifacts has a bearing on any (supposed) ability to recognize differences between DACs/amps?