SMSL DO300 DAC Review

[Avecesare]

good evening, has anyone done any tests with the AES input of the do300? Amir's graphs only concern USB and optical input, I have a Volumio Rivo DAC which in addition to USB also has AES and I wouldn't want to rely only on my ears

 

[pkane]

anyone knows if changing the volume above 0 ( default +2dB for example) may change the sinad? It would stay flat at 125 like the last steps in the SINAD vs Volume graph?

Not by much. I'm measuring this with E1DA's APU notch + Cosmos ADC, so the result is different than Amir's as this setup has lower noise than APx555.

At -0.0dB THD+N is -127.3dB, and at +2.0dB it's -127.8, so 0.5dB better at +2dB setting.

 

[morillon]

Not by much. I'm measuring this with E1DA's APU notch + Cosmos ADC, so the result is different than Amir's as this setup has lower noise than APx555.

At -0.0dB THD+N is -127.3dB, and at +2.0dB it's -127.8, so 0.5dB better at +2dB setting.

View attachment 356565

View attachment 356566

it will be possible to compare with amirm's review a thd-n vs frequency a 48k/24 0db with your cosmos? with of course your "racing" M-T.
;-)

 

[pkane]

it will be possible to compare with amirm's review a thd-n vs frequency a 48k/24 0db with your cosmos? with of course your "racing" M-T.
;-)

Notch filter on APU is only at 1kHz and 10kHz, so will not work for a sweep.

 

[morillon]

i know.. but with only cosmos? (and aes from m-t ?) ;-)

 

[pkane]

i know.. but with only cosmos? (and aes from m-t ?) ;-)

Sure:

 

[morillon]

i know.. but with only cosmos? ;-)

Sure:
View attachment 356596

interresting... we learn about cosmos..and 555
we need an rme now ;-)

 

[pkane]

interresting... we learn about cosmos..and 555
we need an rme now ;-)

I suspect that Cosmos ADC input impedance may be affecting the measurement here. At some point I'll need to retry with the scaler.

 

[morillon]

yes behavior under 100hz..
but otherwise values above are greater than ap, it is interesting..
indeed the measurements with the scaler under 100hz will be interesting ;-)

 

[pkane]

Maybe slightly better with E1DA scaler + ADC:

 

[morillon]

but really not significant either ;-)
it's useful to know...

 

[Alp]

I am torn between the do300 and the RME DAC fs. It's 3 times cheaper and I don't need an eq, but for some reason I think the do300 will be a worse purchase than the RME DAC.

 

[IVX]

Maybe slightly better with E1DA scaler + ADC:

View attachment 356709

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

 

[pkane]

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.

Yes, APU notch + 6dB does something a little better than my previous result with the Scaler:

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

Thanks, Ivan, where can I find the spreadsheet?

 

[IVX]

Paul, I gave you already all that you need - the idea Excel sheet works but you have a chance to implement that better as a bin minus bin subtraction.

 

[pkane]

Paul, I gave you already all that you need - the idea Excel sheet works but you have a chance to implement that better as a bin minus bin subtraction.

Thanks, Ivan! Idea is more difficult, as one has to actually think! Spreadsheet where someone has done the thinking for you is much easier

 

[IVX]

you are welcome.

 

[pkane]

Paul, I gave you already all that you need - the idea Excel sheet works but you have a chance to implement that better as a bin minus bin subtraction.

Here's Multitone Analyzer noise computation for APU+6dB notch into Cosmos ADC 192k (SMSL DO300ES 96k). Without bin subtraction, but with APU compensation curve applied.

Noise is -135 dBA as measured seems in line with your estimates:

 

[IVX]

i.e. if imagine that aliens give you an ideal analyzer, the DAC rather has THD+N <-129db@1k, unlike AP showing that, and all other top DACs, as -124db
PS: I want to let see that idea @JohnPM because I am an active REW user.

 

[pkane]

i.e. if imagine that aliens give you an ideal analyzer, the DAC rather has THD+N <-129db@1k, unlike AP showing that, and all other top DACs, as -124db

Forgive me if I'm asking a personal question... but are you an alien?