Whats up with this?…..perfect dac sounds inferior allthough math says otherwise..

[Oukkidoukki]

So our perfect ( math) dac M400 in the video sounds clearly darker or should I say muffled than d400ex. Was up with this? Didn’t the numbers say there can’t be difference?

 

[fpitas]

We're judging based on a YouTube video?

 

[AdamG]

We're judging based on a YouTube video?

It could be down to the differing Isolators being used?

 

[fpitas]

It could be down to the differing Isolators being used?

Or the DACs aren't both compatible with the cables he used

 

[AdamG]

@Oukkidoukki just ignore us as we’re just being smart asses…

 

[fpitas]

Yes, no offense intended. But I would not trust impressions from a YouTube video.

 

[Deleted member 35357]

I wonder does output impedance have any effect on DAC's?

I know they have been shown to have effect with regard to the HP AMP stages connected to DAC's but does the DAC in itself also have thier own output impedance variance between models?

The impedance from HP Amps colours the freqency response of the headphones depending on thier impedance response of the driver used.
Do all DAC's have varied impedance outputs? Or are they standardized to a known value?

 

[solderdude]

They clearly are using different isolator feet. That could make a world of difference.
Based on the color of the DAC I suspect the silver one will sound brighter than the black one which will be dark sounding.
But the silver one has I2S connection and playing DSD while the black one is using 44.1kHz via the always worse sounding USB connection.
Thank goodness it is SMSL vs SMSL.

Hmm.... I should probably watch the video and see what they are on about.

I wonder does output impedance have any effect on DAC's?

You can stop wondering. The output resistance of the line-outs do not not affect the tonality. They can't and are probably the same anyway.

IF there really are differences it is probably due to different default or set reconstruction filters.

 

[Deleted member 35357]

They clearly are using different isolator feet. That could make a world of difference.
Based on the color of the DAC I suspect the silver one will sound brighter than the black one which will be dark sounding.
But the silver one has I2S connection and playing DSD while the black one is using 44.1kHz via the always worse sounding USB connection.
Thank goodness it is SMSL vs SMSL.

Hmm.... I should probably watch the video and see what they are on about.



You can stop wondering. The output resistance of the line-outs do not not affect the tonality. They can't and are probably the same anyway.

IF there really are differences it is probably due to different default or set reconstruction filters.

I recall seing a list in some thread the other day with some models from same manufacturer did have diffrent output resistance values. some araound 2K while others could be 10K.

 

[fpitas]

I recall seing a list in some thread the other day with some models from same manufacturer did have diffrent output resistance values. some araound 2K while others could be 10K.

With a long enough cable you'll get significant high frequency roll-off. I suspect that's like 25 feet.

 

[pkane]

So our perfect ( math) dac M400 in the video sounds clearly darker or should I say muffled than d400ex. Was up with this? Didn’t the numbers say there can’t be difference?

There's more than 2dB of difference in levels between the two recordings. It's pretty obvious why there would be an audible difference.

 

[Deleted member 35357]

With a long enough cable you'll get significant high frequency roll-off. I suspect that's like 25 feet.

So only if you have real long connections should it be and issue then?

My previous values might have been something else as I went around and checked a few other DAC's and they had 100Ohm for RCA and some other models had 100 & 200Ohm for XLR connections. So there is variance. Not seen any data on if does matter at all though.

Found one with only 20 Ohm RCA.

 

[Sokel]

There's more than 2dB of difference in levels between the two recordings. It's pretty obvious why there would be an audible difference.

You just saved us the trouble measuring it.

 

[fpitas]

So only if you have real long connections should it be and issue then?

My previous values might have been something else as I went around and checked a few other DAC's and they had 100Ohm for RCA and some other models had 100 & 200Ohm for XLR connections. So there is variance. Not seen any data on if does matter at all though.

Found one with only 20 Ohm RCA.

Long cables, or some super high capacitance cable.

 

[BDWoody]

So our perfect ( math) dac M400 in the video sounds clearly darker or should I say muffled than d400ex. Was up with this? Didn’t the numbers say there can’t be difference?

I'd suggest you look into why people need to use proper and appropriate controls, and stop relying on the reports from those who don't.

 

[solderdude]

I recall seing a list in some thread the other day with some models from same manufacturer did have diffrent output resistance values. some araound 2K while others could be 10K.

M400 appears to be 610ohm (due to a muting circuit), XLR = 1.2k. Even with 1.5nF on cable capacity there still is no audible effect.

Only some boutique DACs with weird tube or 'direct' output stages might be in the range you mentioned. These certainly won't be.

 

[jae]

Lazily looking at my level meter there appears to be some differences in peaks between the two samples, no level matching going on? Even a 1-3 dB difference can change the perceived tonal balance of a tune. Feels like a subtle suckout in HF but I'm not sure if that's just due to the recordings. The camera/mic position also seems to change between recordings, and some stuff that looks like blankets/throws in the right corner- the position of the laptop screen changes as well.

 

[fpitas]

Lazily looking at my level meter there appears to be some differences in peaks between the two samples, no level matching going on? Even a 1-3 dB difference can change the perceived tonal balance of a tune. Feels like a subtle suckout in HF but I'm not sure if that's just due to the recordings. The camera/mic position also seems to change between recordings, and some stuff that looks like blankets/throws in the right corner- the position of the laptop screen changes as well.

i think it's safe to say this test lacked certain controls.

 

[sq225917]

What's up with it is that youtube videos shot on camera phones aren't suitable for assessing audio quality. Especially when the DUT are played at different volume levels.

 

[fpitas]

What's up with it is that youtube videos shot on camera phones aren't suitable for assessing audio quality. Especially when the DUT are played at different volume levels.

Exactly