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Sabaj A20d Review (Balanced DAC)

amirm

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This is a review and detailed measurements of the Sabaj A20d balanced stereo DAC with Bluetooth support. It was sent to me by the company. Retail price seems to be US $420 but it is on sale on Amazon for $378.

The form factor is a square "brick" rather than the standard horizontal configuration we usually see:

Sabaj A20d Review Balanced USB Stereo DAC.jpg


A remote is provided which makes navigation rather easy:

Sabaj A20d Review Bluetooth Balanced USB Stereo DAC.jpg


The key debounce timing on the remote is a bit low causing double entry when you are for example changing filter types.

Power is provided through the laptop style external switcher as you see, Wish it was built-in but I see that they are almost out of room on the back.

Sabaj A20d Measurements
Let's get right into it:

Sabaj A20d Measurements Balanced USB Stereo DAC.png


This is what I like to see! Distortion is at -130 dB which is way below threshold of audibility. That results in a SINAD of 120 dB, putting the A20d in our top 20 of best DACs tested, ever:
Best balanced stereo dac review.png



worlds best audio dac review.png


As noted on the dashboard, I had to dial down the output level. Otherwise it goes up to 5.14 volts with better performance still:

Sabaj A20d Measurements THD+N vs level Balanced USB Stereo DAC.png


In case you want to use the RCA output, here is its performance:

Sabaj A20d Measurements RCA USB Stereo DAC.png


Dynamic range at nominal 4 volts and full output is excellent:

Sabaj A20d Measurements DNR Balanced USB Stereo DAC.png


As is multitone performance:

Sabaj A20d Measurements Multitone Balanced USB Stereo DAC.png


Intermodulation vs level test shows the ESS DAC classic IMD hump as we have called it although it is controlled:
Sabaj A20d Measurements IMD Balanced USB Stereo DAC.png


Linearity is superb showing excellent accuracy:
Sabaj A20d Measurements Linearity Balanced USB Stereo DAC.png


I was a bit disappointed in jitter performance over USB:
Sabaj A20d Measurements Jitter Balanced USB Stereo DAC.png


Usually it is the one that is good with Coax suffering a bit but it is the other way around here. I played with the digital PLL control but it made no difference as I suspect it is not used with USB anyway. Fortunately levels are well below threshold of audibility so more of a problem for the eye seeing the graph than the ear.

The usual assortment of filters is provided:
Sabaj A20d Measurements Filter Balanced USB Stereo DAC.png


Using a couple of them we get these satisfactory THD+N versus frequency (wideband):

Sabaj A20d Measurements THD+N vs Frequency Balanced USB Stereo DAC.png


Conclusions
I like simple stories like this: great engineering with closed loop of measuring and optimizing. Slight miss is there in USB jitter but that is about it. Since audible impact is below nil, I let it go and designate the A20d as another "instrument grade" DAC.

I am going to recommend the Sabaj A20d.

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As always, questions, comments, recommendations, etc. are welcome.

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Blumlein 88

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A DAC with Sinad closer to 121 db than 120 db and it ranks only 14th on the list. Further I think of those 14, 12 are below $1000, one of the other 2 not all that much above that number. WOW! Good times!
 

respice finem

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Nice. The only slight letoff is the missing headphone output, and for some, BT.
Then again, balanced and I2S... BTW, given the notoriously bad AVR results, it would be interesting to see that HDMI input measured.
 
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amirm

amirm

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milan616

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I had been going back and forth about getting this as it was a pretty penny, but then the Topping D10 Balanced came out and boom I was sold. It would have matched my Sabaj A20a (and the A20a has a 15V out made for the A20d so you don't need the A20d power brick @amirm ), but difference in SINAD and price thankfully was not justified for my personal use cases.
 

DHT 845

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Luckily it's after d70s
 

DHT 845

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:)
 
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amirm

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GimeDsp

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It is not HDMI. it is special I2S interface that uses HDMI cable and socket.
LOL, funny when looking for info and this pops up. Nice to have the details!
Looks like it has already been shown there are no upsides besides "boutiqueness" to I2S
 
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respice finem

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It is not HDMI. it is special I2S interface that uses HDMI cable and socket.
I know, but, AFAIR I2S is also used by the HDMI standard, so it should be suitable for connecting a TV with eARC, or is it not?
If not, what kind of device will be compatible with it?
 

GWolfman

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I know, but, AFAIR I2S is also used by the HDMI standard, so it should be suitable for connecting a TV with eARC, or is it not?
If not, what kind of device will be compatible with it?
My DSD player can send DSD to my AVR via HDMI. Is it using DoP (as opposed to I²S)?
 

martijn86

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A DAC with Sinad closer to 121 db than 120 db and it ranks only 14th on the list. Further I think of those 14, 12 are below $1000, one of the other 2 not all that much above that number. WOW! Good times!
It is a great thing! The multi tone and linearity graph look like a >$1000,- product. Audiophile influencers hate this though, the rants about these DAC's are so childish. They boil down to Topping/SMSL/Sabaj etc not having 'a sound'. Practically advocating that sub-par engineering is what makes a product audiophile grade and then they ramble on about cables and hi-res music.
 
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amirm

amirm

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I know, but, AFAIR I2S is also used by the HDMI standard, so it should be suitable for connecting a TV with eARC, or is it not?
If not, what kind of device will be compatible with it?
Definitely not compatible with any TV, eARC or otherwise. This is a made up interface that only works with select devices that have the same I2S signaling. It has zero compatibility with classic HDMI AV standard.
 
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amirm

amirm

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My DSD player can send DSD to my AVR via HDMI. Is it using DoP (as opposed to I²S)?
Audio data is sent in the invisible pixels in video over HDMI. Again, it has no relationship with this I2S signaling supported in this DAC.
 
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