SMSL DO300 DAC Review

[Leefer55]

A head scratcher for sure . Needs measuring , sounds like some kind of phase change but who knows why that should be related to the usb connection.

The phase "thing" on the Dean Peer recording is how the recording was made, it is not an artifact to be questioned. I am saying the image is tighter and more 3 dimensional.

 

[Jimbob54]

The phase "thing" on the Dean Peer recording is how the recording was made, it is not an artifact to be questioned. I am saying the image is tighter and more 3 dimensional.

Yes . What you described as the 'tells' from those recordings sounds like the result of one channel being out of phase on one of the usb orientations from your description.

 

[Leefer55]

Yes . What you described as the 'tells' from those recordings sounds like the result of one channel being out of phase on one of the usb orientations from your description.

Are you also able to hear the out of phase starting at 1:42 from the link I provided? What I am trying to say is I hear the out of phase regardless of connection orientation and that one sounds more accurate than the other, to a somewhat small extent.

 

[RandomEar]

Depends on the recording I used.

On Dean Peer's "Lord's Tundra" at the 1:42 mark, the bass guitar solo is played out of phase and the image goes from being a little diffuse and slightly above my speakers to more precise and further above.

On Sara K's "History Repeats Itself", the soundstage is a bit deeper and wider and Sara's voice is a little more precise and further back.

I should add that the increase in precision and soundstage dimension still falls a bit short of my vinyl rig but it's better than the Dragonfly v1.2 I upgraded from.

If you had said that you heard a difference in noise, I would be open to ideas. Maybe a bad USB cable with faulty ground connections, a ground loop or something similar. But stating that the actual music sounds different using a digital signal is simply not plausible. It's digital - either you get music or you get dropouts/nothing. There's no inbetween.

 

[Leefer55]

If you had said that you heard a difference in noise, I would be open to ideas. Maybe a bad USB cable with faulty ground connections, a ground loop or something similar. But stating that the actual music sounds different using a digital signal is simply not plausible. It's digital - either you get music or you get dropouts/nothing. There's no inbetween.

That's exactly what I would have thought and yet here we are. Oh well, not gonna worry about this, just thought it was an experience worth sharing.

Edit 1: I will add, the USB A to C cable I am using cost me $30 CAD so perhaps the cable is the culprit.

Edit 2: The Youtube video I linked to earlier WAS NOT used in this test. I have a DSF file that I created when I ripped the title from my CD. I just listened to the YouTube video and both sounded the same. I was gonna attach the DSF file but it's kinda big...

 

[tades]

No? Seems like it's 3dB down at 14kHz (@48k sample rate):

View attachment 369245


View attachment 369246

Hi Pkane, this curve convinced me to upsample for getting the right curve.
I'm now about to buy the new Shanling Onix that provides DSD64 over I2S.
How will it behave? similar to 44kHz or (as I would expect) similar to upsampled. 88kHz? 176kHz?
Thanks for your kind support

 

[melowman]

Sure:
View attachment 356596

THD rising <70Hz for the internal reason of ES9822, I didn't find a way to reduce that anyhow. About THD rising at >7kHz, this is ES9039Pro profile. You can measure 10k THD with APU and see that H3 will be about -110db, IMHO, it is a shame. BTW, ES9039Q2M has -135db of H3 at 10k test.

As I told you, Cosmos APU has residual THD+N about -135db@1khz and 10Vrms(or 5V with +6db), roughly it is 3x times less than APx555 on a lucky day. All DACs in the range of THD+N -126-130db@1k APx555 will show as -124-125db due to it being the inherent limit of that noisy analyzer. When L7 tested Cosmos APU he tried to measure THD+N of some DAC(not sure which model but 9038Pro) which got -125db at APx555b and next with Cosmos APU->Cosmos ADC->APx500_SW, the result was -127.5db as I remember. Please note, L7 APx555b is a few years newer vs Amir's and L7 always gets a bit lower THD+N on it.
PS: Paul, I guess you (and John-REW) haven't seen my Excel sheet-tool for an ADC residual noise compensation? I intentionally set here A-weighted units to minimize the error of subtracting scalar noise values by narrowing of BW(A-curve is about 100-12500Hz where a noise floor is always flat). And it works not too bad, for instance, Meizu HiFi DAC with bare Cosmos ADC shows SNR -122db(A), after Excel sheet compensation -128db(A), and with APU -130.5db(A). You can subtract noise vectors (bin by bin) and don't care too much if the noise floor isn't flat. Due to the THD+N combo being limited by the N component in most cases, you may compensate for the APU+ADC residual noise and move -135db limit even deeper. The same thing is possible for APx500 but seems AP also haven't seen my Excel sheet

Is that graph above (THD+N vs Frequency measured with the Cosmos ADC) a concern in the end?
This graph does not match Amir’s at all; why is there 30dB (!) more THD+N at 20Hz?
Ivan said his design did bump THD+N in the low end a little bit, but not 30dB. !

What’s happening here?

 

[tades]

No? Seems like it's 3dB down at 14kHz (@48k sample rate):

View attachment 369245


View attachment 369246

Gemini proposes to compensate this by a Highshelf 15500Hz +6dB Q0.8 :

Fréquence	Roll-off du DAC	Correction (HS +6dB)	Résultat Final (Linéaire)
4 000 Hz	0 dB	+0,1 dB	+0,1 dB
10 000 Hz	-1,5 dB	+1,4 dB	-0,1 dB
14 000 Hz	-3,0 dB	+3,1 dB	+0,1 dB
20 000 Hz	-6,0 dB	+5,7 dB	-0,3 dB