Snake oil update! 🐍

[onlyoneme]

For electronics (DACs and amps) , if an item measures as transparent, there’s absolutely no need to listen/audition.

It's an extremely incorrect statement which could be partially correct only if all the measurements were made in the end-user environment with his loudspeakers for example when talking about amps.

 

[Matterhorn]

It's an extremely incorrect statement which could be partially correct only if all the measurements were made in the end-user environment with his loudspeakers for example when talking about amps.

True, that is why I compare audio equipment by using highly resolving wired headphones. IMHO it is the best way to evaluate equipment.

 

[Steve Woodhouse]

It's an extremely incorrect statement which could be partially correct only if all the measurements were made in the end-user environment with his loudspeakers for example when talking about amps.

No, that’s a nonsense.

If you can’t measure in a lab things which are known to be audible, you certainly won’t be able to hear them in the real world.

Just think about it. You create a sine wave, and measure the distortion. It’s so low you can’t hear it.

You’re suggesting you might be able to hear it played on a sine wave, over perfectly balanced, distortion-free headphones, in an enclosed listening room, but you won’t hear it over a pair of loudspeakers in a non-anechoic room, in the midst of music?

That’s quite crazy.

That’s like saying…let’s think.

You attach a product which causes vibration, and attach it to a pice of wood on which you place your gave. Then you measure the point at which you feel it.

What you’re saying is, if you sit on a bumpy bus, on the back seat, sat over the engine, and conduct the same experiment, you’ll be more likely to feel it at that level.

That’s quite crazy, and utterly indefensible.

Bottom line. If you can’t hear it in a precise, controlled environment, you’re not going to hear it in the wild.

It’s like measuring the quietest whisper you can hear in a sealed, silent room, coming down 0.5dB from that so you know you can no longer hear it, then claiming you can hear it in a noisy railway station.

Quite, quite crazy. Utterly illogical. Flying in the face of every scientific principle.

 

[Griff]

It's an extremely incorrect statement which could be partially correct only if all the measurements were made in the end-user environment with his loudspeakers for example when talking about amps.

Agree, and this is probably the thing that gets me thinking about 'blind tests'. A/Bing of two things doing similar things like playing music without something familiar in the mix is something I find very hard.

I remember reading an interview with Tony Andrews of Function One fame. And he said he tested every system he fitted out with the same tune, Gat Decor Passion. His reason is that he knew what the snare drum should sound like and it was so pronounced he could pick up the difference and fix the issue.

Back to the thread and how this links in. I can tell the difference between small changes on my system better than on other people's systems. That's because, in my opinion my familiarity of my own system means change is easier to pick up.

 

[onlyoneme]

No, that’s a nonsense.

If you can’t measure in a lab things which are known to be audible, you certainly won’t be able to hear them in the real world.

Just think about it. You create a sine wave, and measure the distortion. It’s so low you can’t hear it.

You’re suggesting you might be able to hear it played on a sine wave, over perfectly balanced, distortion-free headphones, in an enclosed listening room, but you won’t hear it over a pair of loudspeakers in a non-anechoic room, in the midst of music?

That’s quite crazy.

That’s like saying…let’s think.

You attach a product which causes vibration, and attach it to a pice of wood on which you place your gave. Then you measure the point at which you feel it.

What you’re saying is, if you sit on a bumpy bus, on the back seat, sat over the engine, and conduct the same experiment, you’ll be more likely to feel it at that level.

That’s quite crazy, and utterly indefensible.

Bottom line. If you can’t hear it in a precise, controlled environment, you’re not going to hear it in the wild.

Does the lab use your own loudspeakers as the load? Do you have an idea how real, reactive loads can affect the amp performance? Or even resistive ones but without a constant resistance?

 

[Matterhorn]

And... the evangelists are back

 

[Brantome]

While Elton John thinks Saturday night’s alright for fighting, please bear in mind the group rules and disagree agreeably or I may need to let the sun go down on this thread

Thanks

 

[Mr Ee]

While Elton John thinks Saturday night’s alright for fighting, please bear in mind the group rules and disagree agreeably or I may need to let the sun go down on this thread

Thanks

Two musical references in one sentence!
And I agree agreeably. Let it be, let it be...

 

[Steve Woodhouse]

Does the lab use your own loudspeakers as the load? Do you have an idea how real, reactive loads can affect the amp performance? Or even resistive ones but without a constant resistance?

For a kick off, the post you quoted was talking about DACs, which are measured at RCA/XLR out, do amp output to loudspeaker isn’t relevant.

For amps, different loads are used.

 

[onlyoneme]

For a kick off, the post you quoted was talking about DACs, which are measured at RCA/XLR out, do amp output to loudspeaker isn’t relevant.

I've responded to your statement about dacs AND amps.

For amps, different loads are used.

We are on the WiiM forum, there are references to ASR measurements published here quite often. So, which loads were used in this Amp review?

WiiM Amp Streaming Amplifier Review

This is a review and detailed measurements of the WiiM Amp streaming amplifier. It was sent to me by the company and costs US $299. I was pleasantly surprised by the good bit of weight this small box has. It will help it not slide with the weight of the speaker wires and such. Back panel shows...

www.audiosciencereview.com

 

[steadyshot]

Exactly dummy loads mimicking the impedance curve of a real world speaker which most often dips 4ohms or below should be used. This is no brainer. Not using this is a serious omission and makes the review of an amp worthless

 

[onlyoneme]

and makes the review of an amp worthless

Thx for calling my Amp tests worthless

 

[steadyshot]

Thx for calling my Amp tests worthless

I was trying to back you up but then oh sh*t

 

[Steve Woodhouse]

I've responded to your statement about dacs AND amps.


We are on the WiiM forum, there are references to ASR measurements published here quite often. So, which loads were used in this Amp review?

WiiM Amp Streaming Amplifier Review

This is a review and detailed measurements of the WiiM Amp streaming amplifier. It was sent to me by the company and costs US $299. I was pleasantly surprised by the good bit of weight this small box has. It will help it not slide with the weight of the speaker wires and such. Back panel shows...

www.audiosciencereview.com

That’s an ASR review. I was asked about scientific tests setting the semesters of what is audible.

But for clarity, load dependence is discussed in that review, and I think anyone with half a brain (okay, clearly not everyone reading the review) can figure that, if there’s a load dependence issue with one simple laid presented, it’s not going to magically sort itself out with a complex load.

By the way, the first person to measure applying complex loads was Erin, who’s gone in to compare the WiiM amp against others, and didn’t find an audible issue.

 

[Brantome]

I think anyone with half a brain (okay, clearly not everyone reading the review) can figure that)

Steve, can we dial back on this sort of comment please? Thx

 

[Steve Woodhouse]

Steve, can we dial back on this sort of comment please? Thx

Forgive me.

 

[Steve Woodhouse]

As we’re employing musical references, may I quote Radiohead.

Every time someone tells me they can hear a difference which can’t be measured, my head automatically plays There There, “Just ‘cause you feel it, doesn’t mean it’s there.”

 

[onlyoneme]

load dependence is discussed in that review

With some purely resistive loads. But you don't listen to power resistors, do you?

if there’s a load dependence issue with one simple laid presented, it’s not going to magically sort itself out with a complex load

Is there magic that can determine exactly how speaker X will affect amplifier performance when only measurements taken with resistive loads are available?

the first person to measure applying complex loads was Erin

I don't think he was the first, but he should be applauded for incorporating more complex loads into his procedures.

What about some tests and conclusions here

AIYIMA A07 TPA3255 Amplifier Measurements and Review - LM4562 (and OPA2134) option

AIYIMA A07 TPA3255 Amplifier Measurements LM4562 option I received my A07 yesterday, on January 6, 2021, shipped from Italy. Purchased at Amazon.de and as stated on their website, it arrived without a power supply. I am testing the A07 with 2 different power supplies. One of them is a linear...

www.audiosciencereview.com

or here

Class D AIYIMA A07 amplifier (ABX) listening test

I was curious if inserting AIYIMA A07 TPA3255 class D amplifier in the D/A – A/D loop would be audible. I tested the amp in another thread and found that the frequency response depends, at higher frequencies, on speaker complex impedance, due to amplifier's output LC filter - that is outside...

www.audiosciencereview.com

?

 

[BadMan]

Audioquest carbon optical . I received it today . First impression soundstage is wider and deeper, bass and treble clearer . Bass is more impactful. Micro details much more easily detectable and decay of bass notes .piano is cleaner with absence of smearing while being hefty with nice fast decay . Clean and smooth . In comparison Audioquest pearl although very good , it is overall more fuzzy and less focused than carbon . If you don’t try carbon ever , Audioquest pearl could seem all you need. I could live with pearl but carbon wins easily. If I could quantify the difference is 5-10% better. Also preferable to qed performance coaxial , more natural and clean

do you prefer optical over coaxial, and if yes, why?

 

[steadyshot]

do you prefer optical over coaxial, and if yes, why?

If you employ a good optical cable you get both total galvanic isolation and low jitter and good bandwidth.Even if 24/192 would not work for my dac I wouldn’t care since the difference from 24/96 is trivial .The cable itself does not radiate to the equipment and other nearby cables and also is immune itself from other nearby emi/rfi that also can transfer to the dac .

So in my case I would not upgrade anything else. I found the sweet spot for me in my current setup.