How can DAC's have a SOUND SIGNATURE if they measure as transparent?

[donjoe0]

0.1dB roll-off at 20kHz for instance isn't directly audible but measurable.
That 0.1dB is only 'detectable' on direct switching and a lot of training as that 0.1dB in reality is closer to 0.2dB.
It also cannot be called a 'sound signature'.

It's not always at 20 kHz. Look at the recent and highly gushed over FiiO KA17: it has a V-shaped cutout at 6-9kHz somewhere, rises back up, then rolls off again toward 20kHz, both times it's 0.4 dB below neutral, clearly audible, clearly a sound signature. Or look back at the favorably reviewed Hidizs S8: Amir didn't show the FR plot but you can almost see the information on the 32-tone plot: treble is veiled from 6 to 10k, then rises again. Compare with my Hiby FC3 response: flat flat flat all the way to 20 kHz, real neutrality.

Not all DACs sound the same. Manufacturers are creating measurable "signatures" to draw customers to their side and keep selling new units every year. Competition and continuous sales wouldn't work nearly as well if it was all placebo.

 

[solderdude]

Why would any DAC 'dip' at 6-9kHz ?
Only when some EQ would be used (which it has) you could do that but that is EQ and not the frequency response of the DAC.

KA17_parameters

KA17_parameters

www.fiio.com

The vertical scale on the plots are 1dB/div. Where is the 'sound signature' ?

S8 ... where is the dip ? Where is the 'veil' and where can you 'almost' see that ?

ALL DACs measure differently. NONE are the same that does not mean they also sound different.

 

[donjoe0]

Why would any DAC 'dip' at 6-9kHz ?

For example to push some sounds back and create the illusion of "soundstage depth". Like I told you: to differentiate vs. other products and give customers a reason to keep buying buying buying.

S8 ... where is the dip ? Where is the 'veil' and where can you 'almost' see that ?

Zoom in.

ALL DACs measure differently. NONE are the same that does not mean they also sound different.

What is this, ignoratio elechi? Are you pretending not to understand the exact measurement I told you tends to be different and the amount by which it tends to be different and that research says that amount is audible?

 

[solderdude]

WHERE is the audible threshold reached in the posted FR plots of the KA17 ?
Please zoom in in show the audible 'dip' in the S8 that is considered a sound signature ?
Also the consensus here is not ALL DACs sound the same but when they don't is is very measurable and breaches audible thresholds.

 

[aagstn]

Not all DACs are the same. Manufacturers are creating measurable "signatures" to draw customers to their side and keep selling new units every year. Competition and continuous sales wouldn't work nearly as well if it was all placebo.

It is mostly placebo and has been common in audio for all kinds of cables, dacs, amps and so on for decades. Some manufacturers like PSAudio put audible noise in their DACs to make them sound different but even this is subtle. If it was so true and obvious that dacs, cables and so on sounded different the influencers would be lining up to do a scientific blind test to prove it and shut the doubters up. Instead it is crickets because there is no way they kill the golden goose by testing this. Measurements aren't perfect. There are flaws in dacs that sometimes don't get discovered with just measurements. Audio leaking out RCA jacks, pops and distortion that shouldn't be there when changing bitrates and other faults. Subjective reviews are flawed in almost every way. A YouTube guy telling me something has more color, depth, or other meaningless words when I don't have their listening room or their ears is useless. At least a measurement of noise and distortion is a starting point that will lead me in the right direction to find a good component and not get ripped off with overpriced junk.

 

[donjoe0]

WHERE is the audible threshold reached in the posted FR plots of the KA17 ?

Are you seriously posting a manufacturer's graphs as an argument in the ASR forum? You don't even know how much smoothing they applied when they made that graph. You need independent measurements. I heard it as veiled, then I measured it through my soundcard and I found why I was hearing it as veiled: https://forum.hifiguides.com/t/fiio-ka-17-opinions-and-usage/43721/5

And no, I will not teach you how to zoom in, you're perfectly capable of that at your level of experience, I don't know what game you're trying to play here but I'm not playing. You're just trying to hang on to #2 in my original answer: you don't want to acknowledge hard data that would force you to believe there are audible differences already shown with measurements, in the response of highly popular modern DACs.

 

[MaxwellsEq]

Or look back at the favorably reviewed Hidizs S8: Amir didn't show the FR plot but you can almost see the information on the 32-tone plot: treble is veiled from 6 to 10k, then rises again. Compare with my Hiby FC3 response: flat flat flat all the way to 20 kHz, real neutrality.

I've zoomed in on the picture. Are you identifying that the 2 multitone frequency peaks at between 5 and 10 are a pixel or so below the line?

 

[donjoe0]

I've zoomed in on the picture. Are you identifying that the 2 multitone frequency peaks at between 5 and 10 are a pixel or so below the line?

I'm seeing 3, but yes.

 

[solderdude]

Are you seriously posting a manufacturer's graphs as an argument in the ASR forum? You don't even know how much smoothing they applied when they made that graph. You need independent measurements. I heard it as veiled, then I measured it through my soundcard and I found why I was hearing it as veiled: https://forum.hifiguides.com/t/fiio-ka-17-opinions-and-usage/43721/5

And no, I will not teach you how to zoom in, you're perfectly capable of that at your level of experience, I don't know what game you're trying to play here but I'm not playing. You're just trying to hang on to #2 in my original answer: you don't want to acknowledge hard data that would force you to believe there are audible differences already shown with measurements, in the response of highly popular modern DACs.

Who says your measurement is accurate ?
How linear is your ADC ?
Why would an AP measurement be unreliable ?
Why would a 0.4dB dip be there anyway ?
Ever seen that in any DAC ?
How much smoothing would need to be applied to an AP measurement for such a broad dip to be 'smoothed out' ?
Have you measured it in a different way than using Pauls software ?
Is it possible something on your end is wrong ?
Do you have independent measurements other than your attempt that show the same ?
What was the load you used ?

 

[MaxwellsEq]

I'm seeing 3, but yes.

Interesting. I've never seen multitone used in this way. It's not really a test of frequency response, more a noise and distortion test.

 

[GXAlan]

For the benefit of the thread, this is what @abm0 measured. He has a control measurement of a different DAC showing a more normal response.

Intentional or not, that’s a sound signature for sure that might be difficult to identify all the time in blind testing but could likely be identified some of the time.

 

[donjoe0]

Interesting. I've never seen multitone used in this way. It's not really a test of frequency response, more a noise and distortion test.

pkane's multitone tool does it that way, and it makes sense to me as more similar to music than a tone sweep. And if it makes sense to plot an FR based on a multitone stimulus with hundreds of tones, I'm thinking we should be able to spot some things even in the spike heights if we look close enough, and even with a lower number of tones if the affected band is wide enough.

 

[donjoe0]

Other one: Questyle M15, highly praised, glowing reviews across the board. Does it have a signature? Yes. Very close to inaudible, but not close enough, depending on listener health.

https://cdn.l7audiolab.com/wp-content/uploads/2022/07/Relative-Level-1.jpg

 

[GXAlan]

tagging @pkane to comment on the graphs presented.

If you look at the posts on this page, @abm0 has taken DACs with perceived sound signatures that should be transparent with a 1 kHz test tone, used your multitone software and shown what seems like it should hit the threshold of audibility occasionally.

 

[solderdude]

Has it been shown in a blind test that this HF roll-off is audible ?

Have you ever seen any DAC's with a similar 'dip' in a not difficult to reproduce frequency for a DAC that isn't intentional or defective ?

Care to use another measurement method (say white noise and a sound card) ?

 

[solderdude]

tagging @pkane to comment on the graphs presented.

If you look at the posts on this page, @abm0 has taken DACs with perceived sound signatures that should be transparent with a 1 kHz test tone, used your multitone software and shown what seems like it should hit the threshold of audibility occasionally.

a 1kHz test tone can NEVER show acoustical transparency !

He needs to verify the measurement with another test method.

 

[GXAlan]

a 1kHz test tone can NEVER show acoustical transparency !

He needs to verify the measurement with another test method.

I think people generally like to say that 1 kHz SINAD is a proxy for performance and that unless you were dealing with tubes, virtually any solid state DAC is going to meet the threshold of audibility.

No one is doubting that more methods can be beneficial, such as doing a null test, etc. But the current data does seem compelling unless @pkane says this is a glitch in the software somehow.

It’s like seeing a UFO once and getting a clear picture of it. We want more photos and data, but let’s not ignore the available data that we do have.

 

[solderdude]

I think people generally like to say that 1 kHz SINAD is a proxy for performance and that unless you were dealing with tubes, virtually any solid state DAC is going to meet the threshold of audibility.

It isn't. People that say that do not understand what the measurement shows.
It only shows distortion at a specific level of a 1kHz tone and nothing else. It is in no way a 'measure' of sound quality.

The current measurement must be verified using a different method.
As soon as that measurement is done (alternate method) and still shows then it would have to be repeated at different bitrates and the device should be returned as faulty if it does. I have never seen any DAC do anything like what was shown nor is there an explanation for it that a DAC should do that.

 

[donjoe0]

It’s like seeing a UFO once and getting a clear picture of it. We want more photos and data, but let’s not ignore the available data that we do have.

I'm trying to tell you: it's not a one-off, it's been under our noses for years, usually it's a simple rolloff in the highs like Solderdude immediately correctly assumed, but it seems manufacturers have been getting more creative with it recently, trying to come up with different "flavors of neutral". )

As for replication of my UFO, for what it's worth I did multiple re-plots at different gain levels and with SE vs. BAL-out, and after a firmware reflash.

 

[solderdude]

It needs to be replicated with a different method... say white noise and a simple capture of that (at least 1 minute) and then using something like audacity to show the spectrum.

As stated... I have never seen any DAC do anything like this so the most likely thing is measurement error or a defective device (PEQ stuck in some mode or so)
Passband ripples...sure... roll-off due to poor filtering ... sure.
I don't believe FiiO would intentionally 'tune' a DAC this way to be different and then fake AP measurements to show it is 'flat'.
There is a reason you measure what you measure and is interesting to find out why.
One thing I am sure of... it is not intentional to create a 'sound signature'.