SINAD as an overall figure of merit

[rjp]

Technical question regarding quantitative analysis and ranking..

I saw recently that the WiiM Ultra streamer DAC measure a very high 115 dB SINAD, which is great compared to the hundreds of other DACs measured here.

But why is this SINAD used as an overall metric of quality? The DACs reported in the colored chart seem to be ranked exclusively by this number.

To my understanding the SINAD reported was measured only at a single frequency, 1000 Hz, and only at a single amplitude. What about performance at other frequencies and other power levels?

I am wondering why we believe this single number represents enough of the device's performance roll-up to truly say that one is better than another.

If there has been some prior discussion/technical justification for this please send a link. I would love to read and understand.

Thank you!

 

[voodooless]

There are a shitload of threads on this already. A simple search will show you plenty:

Search results for query: SINAD

www.audiosciencereview.com

 

[staticV3]

What about performance at other frequencies and other power levels?

You didn't read the review, did you?


I love when people parrot this "ASR is a 1kHz SINAD cult" thing that they picked up online, because it shows painfully well how they couldn't be arsed to read even one review to the end

Confirmation bias at its finest.

 

[solderdude]

But why is this SINAD used as an overall metric of quality?

It isn't.

It is a number that is easily ranked and compared.
It says 'something' about noise + distortion distance referenced to 2V (4V for balanced) and at 1kHz only.
It does NOT represent 'DAC sound quality' nor is it buying advise.
It is kind-of a metric that says 'something' about the technical performance of the used components/design.
A high SINAD means distortion (at 1kHz only) is low AND noise is low.
The rest of the review is always far more important and telling than that simple number.
Note that there are 4 tiers where the SINAD numbers fall into.

 

[Grotti]

You are a member for nearly 6 years now and start a thread with a question which is answered many times on ASR? Or even when you read the mentioned review from the beginning to the end....

 

[rjp]

I read several of those threads but didn't see much useful information. Most seemed to turn nasty and suggest that anyone questioning SINAD must be an idiot incapable of knowing what it means, sadly. I've spent my life as and EE in signal analysis and an familiar with the term. I definitely agree it is an important signal quality metric.

My question is more about why we are using the SINAD at just a single input frequency and power as an overall figure of merit in the colorized DAC charts.

It seems to give the impression that everything relevant about signal quality can be rolled up in this one number. But this number is really just showing performance at 1KHz and 5w. Does it say anything about the performance at other frequencies and power levels? If so, what is the basis for this extension?

Is this not the intention of the ranking? Maybe I'm reading too much into it.

 

[staticV3]

Maybe I'm reading too much into it.

Yes, you are.

Just as Amir has a 1kHz SINAD ranking, he also has an output power @32/300Ω ranking, a 50mV SNR ranking, a 40Hz output power ranking, ...

None of these is a definitive "quality" metric, just as the Harman Preference score calculated for speakers and headphones is not a definitive quality metric.

Always read a review in its entirely, learn to interpret and weigh the data according to your needs, and you will be vastly better informed when it's time to choose your equipment.

 

[NTK]

Is this not the intention of the ranking? Maybe I'm reading too much into it.

If you have a list of DAC's, how would you order them in the list? Alphabetical order? By date of review? Cost? Weight? Width to height ratio? Drop test result? Crush strength? Random?

Any ordering method can be and will be criticized.

 

[rjp]

It isn't.

It is a number that is easily ranked and compared.
It says 'something' about noise + distortion distance referenced to 2V (4V for balanced) and at 1kHz only.
It does NOT represent 'DAC sound quality' nor is it buying advise.
It is kind-of a metric that says 'something' about the technical performance of the used components/design.
A high SINAD means distortion (at 1kHz only) is low AND noise is low.
The rest of the review is always far more important and telling than that simple number.
Note that there are 4 tiers where the SINAD numbers fall into.

I agree with this. I guess my question comes from the fact that the SINAD is the single quantity ranked in the color coded DAC charts. That chart along with the review comments that celebrate every new high entry awarded, gives the impression that DACS up the top are better.

I guess I read too much into it. I agree it is just one metric of performance and it easily ranked.

 

[rjp]

Yes, you are.

Just as Amir has a 1kHz SINAD ranking, he also has an output power @32/300Ω ranking, a 50mV SNR ranking, a 40Hz output power ranking, ...

None of these is a definitive "quality" metric, just as the Harman Preference score calculated for speakers and headphones is not a definitive quality metric.

Always read a review in its entirely, learn to interpret and weigh the data according to your needs, and you will be vastly better informed when it's time to choose your equipment.

Thanks staticv3, I understand that the SINAD is just one number in a much more comprehensive review. I always read the whole review, and usually most of the comments as well. Maybe I was more about looking out for the other (perhaps less technical) guy who might not understand this and simply look at Amirs SINAD chard and conclude one DAC is better than another because of this number. Over many years of reading comments here I do get the impression it is sometimes viewed that way.

 

[JustJones]

I am wondering why we believe this single number represents enough of the device's performance roll-up to truly say that one is better than another.

I have no idea why you believe that. It looks like everyone who's responded so far doesn't and neither do I. Why do you?

 

[Guddu]

Probably timing of this thread should relate to some YouTube video came out yesterday (or day before).
Someone I met last evening mentioned this last evening.

Fact is, one YouTube video might spoil your hours of reading and understanding sometimes.

 

[ahofer]

But why is this SINAD used as an overall metric of quality?

It isn’t, that’s a strawman often used by critics of ASR. But it’s a good starting point as a signal of *engineering* quality. You’d have to have an awfully good reason to take the trade off and not have good SINAD (can anyone think of an example that is accurate, rather than a colored sound?).

One can take the perspective that any measurement or suite of measurements is an incomplete summation of a component. I think it is much harder to dismiss measurements as a form of quality triage. I’m comfortable buying electronics on measurements. Speakers need listening, but I use measurements to filter out hundreds of options that might otherwise waste my time.

 

[rjp]

I have no idea why you believe that. It looks like everyone who's responded so far doesn't and neither do I. Why do you?

I don't believe it. Take a look at my post. I'm asking why do "we" believe it, collective. I am glad to see there are at least 5 of you who do not

If you take a read through some of the posts in the various threads you may see people believing this number irepresents the DAC quality.

My guess is that the others are too afraid of the abuse to speak up?

 

[voodooless]

I'm asking why do "we" believe it, collective.

It’s just FUD other places spread.

I read several of those threads but didn't see much useful information. Most seemed to turn nasty and suggest that anyone questioning SINAD must be an idiot incapable of knowing what it means, sadly.

Where does it say that? Reads like more of the same FUD.

 

[ahofer]

you may see people believing this number irepresents the DAC quality.

Or, rather, restating my “indicator of engineering quality” remark above, asking why you would bother spending any more time on a DAC that has done relatively poorly in its most basic function when cheaper DACs have not.

 

[VintageFlanker]

The DACs reported in the colored chart seem to be ranked exclusively by this number.

Yop. The DACs listed in SINAD Chart are ranked by SINAD....

 

[RickS]

Technical question regarding quantitative analysis and ranking..

I saw recently that the WiiM Ultra streamer DAC measure a very high 115 dB SINAD, which is great compared to the hundreds of other DACs measured here.

But why is this SINAD used as an overall metric of quality? The DACs reported in the colored chart seem to be ranked exclusively by this number.

To my understanding the SINAD reported was measured only at a single frequency, 1000 Hz, and only at a single amplitude. What about performance at other frequencies and other power levels?

I am wondering why we believe this single number represents enough of the device's performance roll-up to truly say that one is better than another.

If there has been some prior discussion/technical justification for this please send a link. I would love to read and understand.

Thank you!

As already pointed out this topic has been discussed here ad nauseum. Amir even did an AES paper that discusses. See here:

AES Paper Presentation on DAC Measurements (Video)

As some of you know, I presented a paper at this years Audio Engineering Society on measuring over 450 DACs. All the tests were detailed in the paper together with motivations and learnings from the multi-year project. The paper is only available for a fee (link below). AES asked for a short...

www.audiosciencereview.com

You complain about SINAD and how it might mislead others but can see your argument is getting circular. As mentioned, we have existing comparable threads and, lacking better direction, this one likely gets merged.

 

[Oddball]

I don't believe it. Take a look at my post. I'm asking why do "we" believe it, collective. I am glad to see there are at least 5 of you who do not

If you take a read through some of the posts in the various threads you may see people believing this number irepresents the DAC quality.

My guess is that the others are too afraid of the abuse to speak up?

Why do you think that SINAD is limited to DACs? Or are you particularly concerned with DACs? It certainly appears to be a broader measure of transparency. Engineering efforts to get to a higher SINAD are admirable and desirable by all means. DAC specs are just the beginning, implementation of a specific DAC can take its specs down significantly, which also speaks of design.

But, I'd take Denon 3800H with full Dirac pack anytime over anything that measures +20 SINAD compared to 3800H. Even though I do think that Denon should have done better, and hopefully they will do with 3900H that might be out soon.

 

[rjp]

Wow, tough crowd. Why be so unfriendly? A thought a little technical discussion would be fun. Oh well, thanks for posting Amir’s paper. That should help with the questions I’m asking.