Are Measurements of Schiit Yggdrasil DAC Inconsistent?

[SIY]

Well I would like to test a multi test tone anyway to see what it would be like.
You know something with like 5 tones or more just to see.

I spoke to amir about this before and he said that he was actually working on a way to test some sort of music via the analyzer for comparison.

I routinely use 42 tone multitones in my reviews. So far, any DAC or amp that's basically clean sails through it.

 

[dc655321]

Well I would like to test a multi test tone anyway to see what it would be like.
You know something with like 5 tones or more just to see.

IIRC, @SIY has posted or linked to multi-tone measurements he has performed.

EDIT -- speak of the devil... he beat me to it.

 

[Jimster480]

I routinely use 42 tone multitones in my reviews. So far, any DAC or amp that's basically clean sails through it.

Link me?

 

[SIY]

Here's a few examples. Go over to my website or any of my AudioXpress articles (print) for more. (the second plot is for the CEntrance DACportable)

 

[Blumlein 88]

I see,
Well if anything doing these multi tone tests would help I think to turn the skeptics into believers. As I have friends who tell me that "analyzer's aren't your ears and music isn't just one tone".

I suppose anything is possible. I've tired of many such things because you can do it over and over. Someone just asks for something else or want it done again and again despite it already being done.

At one time regarding cable sound I sent actual music from DAC to ADC, and did nothing other than swap cables. Then nulled the various results against each other getting very little left other than thermal noise. Didn't convince anyone I don't think. That sort of thing is sensitive enough you could compare 1 meter vs 3 meter interconnects and get a little music left over. That was due to the different amount of time it took the signal to travel 3 meters vs 1 meter. You know like a few nanoseconds timing difference.

 

[Blumlein 88]

Here's a few examples. Go over to my website or any of my AudioXpress articles (print) for more. (the second plot is for the CEntrance DACportable)

View attachment 14176

View attachment 14177

I see an extra spurious tone at like -135 db near what 16 khz into the 600 ohm load, and maybe a hint of one at 8hz. Massive degradation with multiple tones.

I was going to do a 2 vs 4 vs 8 tone example, but I think yours should suffice.

 

[solderdude]

I think that the only possibilities here exist in how a DAC actually plays back music.
Let me explain what I mean by this, because its very common in the world of computers to over-optimize specific performance or "cheat" in certain respects.
So when you are playing music, there are many tones playing at the same time. These tones are obviously the music itself which is compromised of possibly 50 different tones at the same time, vs 1-2 tones at once. Therefore DAC vendors can indeed optimize single and dual-tone performance far beyond that of say 50 tone performance and without that multi-tone performance measured it leaves room for error.

A DAC does not produce 'music' or 'separate tones' at all. It gets instructions which voltage to create and a short time later (the next sample) the next voltage to make.
It does not care if it is 'music' or a test signal. It doesn't care about frequencies, phase, amplitude at all. It just generates the 'expected' voltage at any point in time.

Interpolation (in a clever way) calculates the most probable in-between values when oversampling or converting to less bits (DS).
It really is only re-creating a varying voltage over time dictated by the applied sample values.
Nothing more nothing less.
There is no magic. Just clever coding and electronics.

 

[Fitzcaraldo215]

I see,
Well if anything doing these multi tone tests would help I think to turn the skeptics into believers. As I have friends who tell me that "analyzer's aren't your ears and music isn't just one tone".

Good luck with that. Do it and they will just come back with some other lame rationale re the measurements, asking others to prove it, not that they have any proof themselves. They just have their beliefs, unshakably against measurements.

 

[RayDunzl]

Here's a few examples.

Nice and clean.

I'm an in-room kinda guy...

88 piano sine fundamentals in-room with DRC (that hasn't been tuned up for a while).

JBL LSR 308 and DRC

Martin Logan reQuest with cheeze subs and DRC

Less IMD on the panels at higher frequencies?

 

[SIY]

I see an extra spurious tone at like -135 db near what 16 khz into the 600 ohm load, and maybe a hint of one at 8hz. Massive degradation with multiple tones.

I was going to do a 2 vs 4 vs 8 tone example, but I think yours should suffice.

Where I saw a difference was my tests of coupling caps (V-Cap PTFE vs Radio Shack bipolar electrolytic). And not in the direction that would make an audiophile happy...

 

[rebbiputzmaker]

Where I saw a difference was my tests of coupling caps (V-Cap PTFE vs Radio Shack bipolar electrolytic). And not in the direction that would make an audiophile happy...

Everyone knew how good the bipolar shack caps were.

 

[Jimster480]

A DAC does not produce 'music' or 'separate tones' at all. It gets instructions which voltage to create and a short time later (the next sample) the next voltage to make.
It does not care if it is 'music' or a test signal. It doesn't care about frequencies, phase, amplitude at all. It just generates the 'expected' voltage at any point in time.

Interpolation (in a clever way) calculates the most probable in-between values when oversampling or converting to less bits (DS).
It really is only re-creating a varying voltage over time dictated by the applied sample values.
Nothing more nothing less.
There is no magic. Just clever coding and electronics.

Eh, that is a very simple stupid way to describe a DAC.
You could say the same thing about a CPU, but different amounts of instructions at the same time cause different levels of performance.

 

[SIY]

Eh, that is a very simple stupid way to describe a DAC.

But correct. Unless the DAC is broken or "designed" rather than engineered.

 

[Jimster480]

But correct. Unless the DAC is broken or "designed" rather than engineered.

But yet not every DAC has the same level of performance.
Just like not every CPU has the same level of performance, and not every task done is done at the same speed.
For DAC's different multitudes of tones could change the overall performance, and considering that this is a scientific forum.... just claiming that there isn't a point to testing things doesn't really fly and seems pretty subjective to me.

 

[amirm]

For DAC's different multitudes of tones could change the overall performance, and considering that this is a scientific forum.... just claiming that there isn't a point to testing things doesn't really fly and seems pretty subjective to me.

What is being described is correct Jim. Multi-tone tests results tend to be harder to interpret and don't reveal anything more.

 

[SIY]

But yet not every DAC has the same level of performance.
Just like not every CPU has the same level of performance, and not every task done is done at the same speed.
For DAC's different multitudes of tones could change the overall performance, and considering that this is a scientific forum.... just claiming that there isn't a point to testing things doesn't really fly and seems pretty subjective to me.

OK, let's see an example of this "could."

With engineered DACs and amplifiers, I haven't seen one yet. Nor would I expect to because they're, for all intents and purposes, linear time invariant.

 

[Jimster480]

OK, let's see an example of this "could."

With engineered DACs and amplifiers, I haven't seen one yet. Nor would I expect to because they're, for all intents and purposes, linear time invariant.

How could I show an example without any measurements being done?
Hypothesis are shot down because of no prior evidence? Doesn't seem very scientific to me.

 

[SIY]

How could I show an example without any measurements being done?
Hypothesis are shot down because of no prior evidence? Doesn't seem very scientific to me.

I just showed you some. I've done quite a few. Or is this the "never enough" sort of argument?

Your hypothesis, it's up to you to show contrary data.

 

[Jimster480]

What is being described is correct Jim. Multi-tone tests results tend to be harder to interpret and don't reveal anything more.

Why are they harder to interpret? You could in theory make infinite tones and then filter them from the output and see how much noise is left over.
How is this different from your other tests?

I just showed you some. I've done quite a few. Or is this the "never enough" sort of argument?

Your hypothesis, it's up to you to show contrary data.

In your tests they are simply just graphs of multiple tones, nothing else is shown. What is that graph supposed to represent? That the DAC can make multiple tones?

 

[SIY]

Good luck with that. Do it and they will just come back with some other lame rationale re the measurements, asking others to prove it, not that they have any proof themselves. They just have their beliefs, unshakably against measurements.

You have been proved correct. Well done.