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SMSL M400 Balanced USB MQA DAC Review

SuicideSquid

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Please show where I have mentioned that I assume that I have.


So where is Benchmark's ABX testing system lacking in scientific rigour ?

Why does Amir measure measure out of band noise in amplifier power supplies ?.

Rather than constantly attacking me show some measured science to support your absolute objectivism. Surely the proven science has simple answers to my often asked questions.

You claimed to be able to perceive a 2dB difference in SINAD between two dacs that both measure effectively perfect across the audible spectrum. This is extremely unlikely.

There is nothing wrong with Benchmark's description of their ABX system. The problem is in your interpretation of their methods and measurements. A problem with how some DACs reconstruct a waveform could not possibly explain a perceived difference between two amplifiers, neither of which are converting digital to analog. Further, Benchmark repeatedly emphasizes the need for level-matching and blind testing in order to ensure you're perceiving actual differences between devices, and not merely experiencing expectation bias. This is what we've been talking about the entire time. If you're just switching back and forth between two devices without care to blind yourself as to which device you're listening to, and without care to ensure that both devices are outputting the same signal level, you're going to fool yourself - either by simply preferring the louder device, or by thinking you're hearing differences that aren't there.

I cannot speak for Amir, but I understand that out-of-band noise is often measured for several reasons - too much ultra high frequency noise can suggest mistakes in design that may manifest in other areas as well, may adversely affect the efficiency of a system (if you're pumping inaudible noise through a system, you're still having to expend energy amplifying that noise, which is not good), and in some rare cases UHF noise can cause artifacts in the audible spectrum; however, in all of these cases, this is a measurable phenomenon, and in no case would I expect the difference between ultrasonic noise between the Benchmark and Hypex amplifiers to make a measurable difference, because across the board the amount of noise is miniscule.

The simple fact of the matter is that the measuring devices Amir and others use to test DACs and amplifiers are far more sensitive than the human ear, and if you think you're detecting either unmeasurably tiny differences between devices, or measurable differences that are generally considered to be below the threshold of human hearing, you're probably fooling yourself, and the only way to be sure that you're not is to do a proper double-blind test.

I am also not sure you understand what objectivist means. If two devices measure differently and you prefer the one that measures worse, awesome, more power to you. You're not wrong. Listening is ultimately the final arbiter of what sounds good to you. But you have to be listening in a way that ensures you're not fooling yourself. Everyone - me, you, the writers for WhatHiFi and Stereophile - are easy to fool, because we're human beings, and we have limitations. You must take those limitations into account when designing listening tests to try and detect tiny variations in electronics, or else you're going to hear differences that aren't there, and end up dying on a ridiculous hill like 'I can hear the difference between 121 SINAD and 123 SINAD" or "ultrasonic noise measuring below -120dB makes a difference in the audible spectrum".
 
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Mr.Ian

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You claimed to be able to perceive a 2dB difference in SINAD between two dacs that both measure effectively perfect across the audible spectrum. This is extremely unlikely.

There is nothing wrong with Benchmark's description of their ABX system. The problem is in your interpretation of their methods and measurements. A problem with how some DACs reconstruct a waveform could not possibly explain a perceived difference between two amplifiers, neither of which are converting digital to analog. Further, Benchmark repeatedly emphasizes the need for level-matching and blind testing in order to ensure you're perceiving actual differences between devices, and not merely experiencing expectation bias. This is what we've been talking about the entire time. If you're just switching back and forth between two devices without care to blind yourself as to which device you're listening to, and without care to ensure that both devices are outputting the same signal level, you're going to fool yourself - either by simply preferring the louder device, or by thinking you're hearing differences that aren't there.

I cannot speak for Amir, but I understand that out-of-band noise is often measured for several reasons - too much ultra high frequency noise can suggest mistakes in design that may manifest in other areas as well, may adversely affect the efficiency of a system (if you're pumping inaudible noise through a system, you're still having to expend energy amplifying that noise, which is not good), and in some rare cases UHF noise can cause artifacts in the audible spectrum; however, in all of these cases, this is a measurable phenomenon, and in no case would I expect the difference between ultrasonic noise between the Benchmark and Hypex amplifiers to make a measurable difference, because across the board the amount of noise is miniscule.

The simple fact of the matter is that the measuring devices Amir and others use to test DACs and amplifiers are far more sensitive than the human ear, and if you think you're detecting either unmeasurably tiny differences between devices, or measurable differences that are generally considered to be below the threshold of human hearing, you're probably fooling yourself, and the only way to be sure that you're not is to do a proper double-blind test.

I am also not sure you understand what objectivist means. If two devices measure differently and you prefer the one that measures worse, awesome, more power to you. You're not wrong. Listening is ultimately the final arbiter of what sounds good to you. But you have to be listening in a way that ensures you're not fooling yourself. Everyone - me, you, the writers for WhatHiFi and Stereophile - are easy to fool, because we're human beings, and we have limitations. You must take those limitations into account when designing listening tests to try and detect tiny variations in electronics, or else you're going to hear differences that aren't there, and end up dying on a ridiculous hill like 'I can hear the difference between 121 SINAD and 123 SINAD" or "ultrasonic noise measuring below -120dB makes a difference in the audible spectrum".
At the end of the day, whatever the measurements, what sounds best to the listener, subjective, objective or just bullxxxxx has to take precendent
 

misterdog

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When musicians create music, do they measure it to ensure it sounds as good as they would like, or listen to it ?

Great music has been made long before any equipment existed to measure sound, how was that possible without measurement ?
 

SuicideSquid

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When musicians create music, do they measure it to ensure it sounds as good as they would like, or listen to it ?

Great music has been made long before any equipment existed to measure sound, how was that possible without measurement ?
You're not serious.
 

A Surfer

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@SuicideSquid This isn't even a conversation worth continuing. Clearly misterdog is unable to have any perspective beyond his own, a perspective with no basis in scientific evidence. It is fine misterdog, enjoy things as you wish, delude yourself as much as you wish into believing you are hearing these differences. You have that right, but don't think for a moment that your perspective has any scientific merit as it most certainly does not.
 

Mr.Ian

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*unless you're imagining it.
To be honest i dont really care if i am imagining or not, i like what i like. If a d10 or e30 or whatever sounds the same to the listener that's s great they have saved some serious money.
 

SuicideSquid

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To be honest i dont really care if i am imagining or not, i like what i like. If a d10 or e30 or whatever sounds the same to the listener that's s great they have saved some serious money.
That's fine if you don't care about wasting money and you're not evangelizing nonsense to others. When people start coming around these parts saying "X is better than Y and you should spend money on X" (or when companies start saying "our product is better so give us your money") when there's no measurable difference, then I'm free to tell those people they're full of it.
 

A Surfer

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Absolutely, pushing back at the echo chamber of audio mythology and disinformation is almost a duty. The panderers and accidental industry shills are so loud and proud that they need to be countered. And I am not saying anybody in this thread are those, I'm speaking generally and philosophically.
 

Astoneroad

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... I'm speaking generally and philosophically.
... speaking Generally... Patton was an asshole... speaking philosophically... so was Machiavelli. Don't spend money on either of them. My subjective choices would be generally.... Sargent Pepper... and philosophically... Descartes. (Sorry... I can't locate the spinorama for either of them... so take it for what it's worth... which is nothng.):cool:
 

SMSL-Mandy

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Output/imput impedance is one ratio that does warrant attention especially with passive pre amps and some pro audio gear. Fortunately i am feeding balanced into 300k. And its a recent model m400.
So many person wonder: If smsl m400 when used in variable mode with power amp makes a difference in sound quality vs when used in fixed mode with a pre amplifier?

In short do i need another preamplifier when connecting smsl m400 with power amplifier?


It will be different, because the performance of the amplifier is different at different input amplitudes, our suggestion is to turn up the volume of the amplifier, and then use the M400 to control the volume
You can experiment a lot yourself, and the sound quality will vary a lot, so we stick to the built-in volume control on all our codecs.

Thanks
 

Lupin

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It would appear though that some cannot go past the words 'listening' or 'subjective' without turning into Pavlov's dog and having to type the words 'expectation bias' on a forum.
I very well can but Audio Science Review forums is not the place to go into what one (think to) hear and subjective opinions about every single DAC. There are other places for that.

Shame really as this excludes many from participating on this forum.
Honestly.. thank god!!
I really hope those "many" stick to places like Head-Fi where baseless subjective statements makes you "knowledgeable" and an "expert" carried on hands by the mindless flock..

There is a reason I avoid places like Head-Fi, I really don't care what your or anyone's subjective opinion is about a DAC.
Every single person perceives audio in his/her own personal way, have his/her own tastes and preferences. Therefor your personal subjective opinion how something sounds is utterly meaningless to anyone else.
 

A Surfer

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....Therefor your personal subjective opinion how something sounds is utterly meaningless to anyone else.
Not meaningless as they all band together and form an echo chamber where everybody suddenly "hears" the increase in sound quality, especially after you add the right cable and burn in the headphone long enough.
 

raif71

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Not meaningless as they all band together and form an echo chamber where everybody suddenly "hears" the increase in sound quality, especially after you add the right cable and burn in the headphone long enough.
Yes, agree with you there that it is not entirely meaningless. For example, I do value what other people's experience though I know it is only theirs and may not apply to me or anybody else but enough consensus may make me rethink and not based my purchasing only to measurements. What would be perfect are good measurements and good sound experiences on a product and the other case are bad measurements and bad sound experiences. Maybes, are the ones that fall in between the two extremes.
 

Lupin

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Yes, agree with you there that it is not entirely meaningless. For example, I do value what other people's experience though I know it is only theirs and may not apply to me or anybody else but enough consensus may make me rethink and not based my purchasing only to measurements.
Still believe it is meaningless.

Good example:
I modded my Fostex headphones in such a way that it just gives a little more "oomph" in the lows, nothing excessive just a tiny bit. With this mod I believe that these headphones sound amazing (especially considering the price bracket).
I have lend my Fostex to a friend at work and after 3 days he gave them back to me. He believes that these Fostex were the worst sounding headphones he listened to quite some time. Not nearly enough bass, he thought they sounded like tin cans..

So who is right here? Who's subjective opinion weighs heavier? Who's opinion should you base your purchase decision on?
 

A Surfer

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When in doubt, I'll settle all subjective disagreements.
 

raif71

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Still believe it is meaningless.

Good example:
I modded my Fostex headphones in such a way that it just gives a little more "oomph" in the lows, nothing excessive just a tiny bit. With this mod I believe that these headphones sound amazing (especially considering the price bracket).
I have lend my Fostex to a friend at work and after 3 days he gave them back to me. He believes that these Fostex were the worst sounding headphones he listened to quite some time. Not nearly enough bass, he thought they sounded like tin cans..

So who is right here? Who's subjective opinion weighs heavier? Who's opinion should you base your purchase decision on?
Maybe you misunderstood...I demo gears before buying them (well almost, especially the pricey ones). Measurements and subjective reviews from others help me to pinpoint what to buy and what to demo.:)

Edit: I don't do mods and I have a friend who really dig bassy headphones but when I listen to them, yes boomy they may be but to me the voices sounded muffled. To each their own.
 
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mrjayviper

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Per the review , Sharp and Short Sharp are as close as you get to brickwall

index.php
for someone not familiar with reading "audio" graphs, how would I read this? Thanks

---------

On another question, it seems the firmware files for this devices is NOT available anymore from smsl-audio.com? (the DAC section is empty)
 
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Mr.Ian

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do someone not familiar with reading "audio" graphs, how would I read this? Thanks

---------

On another question, it seems the firmware files for this devices is NOT available anymore from smsl-audio.com? (the DAC section is empty)
Q1 the signal/volume gets lower once the signal gets above 20000hz some filters the volume falls away very quickly at high levels. Different filter settings adjust how quickly.

Q2 you are correct as far as i am aware at present there are no downloads available
 
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