Review and Measurements of SMSL Sanskrit 10th DAC

[amirm]

Yes roughly 100 other DACs didn't have this issue. But it doesn't mean this one is problematic because of the issue --- This one is not powered by AC by design, while other 60 DAC is. And another 25, a power supply is provided by manufacturer, or it's a portable amp with battery. For the last 15 usb-powered DACs with no power supply, you sometimes use a $300 linear power supply to test them.

I don't know where you are getting any of this. I have tons of DACs that work just fine and dandy with USB as their only source of power. Most have only one USB jack so you can't power them externally even if you wanted to (without building special cables, etc. which I don't do).

You're not testing your DACs under exactly the same condition and reading the same parameters, which makes your performance benchmark meaningless -

Nonsense. I have a template for testing DACs and I bring them up and connect three cables: USB, and RCA. There is nothing different. I post the exact screenshot of the analyzer which shows every parameter for full scrutiny.

Again, I concede there may be an issue with the product

Maybe? Where does logic come from? The company itself says it needs more USB power. When I add an external supply that accomplishes that and the problem goes way. Where is the "maybe" in that?

You seem to still be upset that your company's product didn't measure well and now complain to cast doubt on validity of measurements (instead of compelling your company to improve its products). You are simply making thing worse for yourself when you do this in a thread where my measurements have actually pointed out an issue with a product that is confirmed by the company and my results.

 

[yue]

What for requirements are there for the power supply? 5V and 1,5 Watt capable, at least?

The power supply @amirm uses to produce good result is from Schiit. It's 5V 1A, so a 5W power adapter is sufficient to power it.

On amazon an Apple adapter cost only $11.5, with very, very good power quality.
Other adapters cost as low as $1 if you buy in bulk.

 

[yue]

Nonsense. I have a template for testing DACs and I bring them up and connect three cables: USB, and RCA. There is nothing different. I post the exact screenshot of the analyzer which shows every parameter for full scrutiny.

In the quote I mentioned you plotted headphone out vs DAC line out SINAD value in the same plot, which is completely unfair and misleading.

Maybe? Where does logic come from? The company itself says it needs more USB power. When I add an external supply that accomplishes that and the problem goes way. Where is the "maybe" in that?

Maybe your computer's USB power is too low. I don't see it as a design issue --- rather I would recommend improving the manual instruction.

You seem to still be upset that your company's product didn't measure well and now complain to cast doubt on validity of measurements (instead of compelling your company to improve its products). You are simply making thing worse for yourself when you do this in a thread where my measurements have actually pointed out an issue with a product that is confirmed by the company and my results.

Come on, I am not upset about it at all. I didn't even mention it once in this thread.


I am upset that you are not conducting scientific experiment at all --- why powering your Apple Pi with a $300 linear power supply? try to power it with your PC then?

If you are not testing all USB-powered DACs using the same power supply, you are simply doing it wrong.

Anyway I made my points very clear --- people need critical thinking when reading your measurements. I won't reply further on this issue.

 

[garbulky]

Well i find it interesting that introducing a better power supply (the modi power supply) IMPROVED the USB performance over the SPDIF SINAID. How is the device powered in SPDIF mode? Did you try it with the modi power supply?

 

[trl]

As stated by the SMSL engineer: "Dear amir,our engineer think maybe that is the power is not engough to the usb,the power consumption of USB input is biger than the S/PDIF. Can you change a PC power supply for testing?Thank you very much.If have any question can contact me.I'll do my best to help to find out the problem."

Probably the USB port is not handling additional power needed by the USB transport. S/PDIF is getting the power from the same +5V provided by the USB port (or adapter, if connected). For example the XMOS XU208 takes 170mA out of the max. 500mA the USB2 port can provide, that would be 1/3 of total power provided by the USB2 port.

 

[amirm]

Well i find it interesting that introducing a better power supply (the modi power supply) IMPROVED the USB performance over the SPDIF SINAID. How is the device powered in SPDIF mode? Did you try it with the modi power supply?

For S/PDIF testing, I left the same USB cable plugged in. So no external power supply. I did not try S/PDIF with modi power supply.

 

[amirm]

If you are not testing all USB-powered DACs using the same power supply, you are simply doing it wrong.

I don't test USB DACs with USB power supplies. I simply connect them to the same USB ports on my computer.

Besides, USB DACs better not have vagaries that depend on USB ports or they will have different performance on every computer. Fortunately well designed ones all have post regulators and isolation from USB so they don't care what port you plug them into.

Your comments are exactly what I hear from manufactures whose products don't perform well: "oh, why don't you test my product on first Tuesday of the month when it is full moon?" It is the same illogical argument that I have been explaining: products that connect to computers need to deal with any and all USB port fidelity. What the heck are we buying in an external DAC if it is not isolation from variations in computers they connect to?

You seem to be thinking we should bend to technology to make it do what it is supposed to do. That is the opposite of what we are about here. We are on the side of consumers, not manufacturers. We spend good money on these audio products in order to get better fidelity. We are not here to test things in isolation with some specialized USB power supply as to make manufacturers happy.

There are plenty of products that don't ask the user to do anything to get superb performance and for very little money. That $9 Apple dongle for example far outperformed the dongle you have been defending. And there are countless higher end products with excellent performance -- again with no handholding.

 

[yue]

I won't discuss about the power supply issue further but I want to be clear that

That $9 Apple dongle for example far outperformed the dongle you have been defending.

I am not defending the Google dongle here. I am a Google software engineer but I use no Google hardware products at all. I neither design nor has any relationship with hardware products the company is building. I remember there are countless times I mentioned in this forum that Apple devices are the best --- they are cheap, and performs so well that it's meaningless to purchase an external DAC, as any improvements would be inaudible. If there're anything that you and I agree upon, I believe recommending Apple products is.

 

[Hugo9000]

If this solves it that would be great.
This is the 1st desktop SMSL DAC I have seen that uses USB power instead of a separate wall wart.

Why a separate USB power input? There is confusion on this point:

The user guide indicates the auxiliary USB power input is for when using with phones/low powered USB devices so as not to overdrive the phone's USB circuits. AND that "you may not use a Quick-Charge power supply because it may output over 5V, that is dangerous for this unit."

However, the specifications section of the manual indicate 1.5W power consumption which is a good bit above USB 2/3 spec.

A review of the Sanskrit 10 at audiophinics.fr describes the use of the USB power port differently. It states: "To isolate the audio signal from the noise coming along the power supply, two USB entries are present: one dedicated to data only and the other dedicated exclusively to the power supply. Thanks to this configuration, the audio source is not in charge of powering the DAC - which is generally poor in this function - and it is quite possible to connect this USB input to a real regulated linear power supply that meets the audiophile standards to maximize your listening experience."

I do not believe a USB power supply ships with the Sanskrit 10th. But if this indeed solves the issue that would be good to know.

I apologize if this is a stupid question whose answer should be obvious to me, but how do I know that a 5V power supply is not "quick-charge" and could output over 5V and damage the unit? This type of warning is why they should have just added a couple of dollars to the price and included a "wall wart" themselves, I guess. lol

 

[GGroch]

I apologize if this is a stupid question......how do I know that a 5V power supply is not "quick-charge" and could output over 5V and damage the unit? This type of warning is why they should have just added a couple of dollars to the price and included a "wall wart" themselves, I guess. lol

Not stupid. "Quick Charge" is a proprietary Qualcomm charge system for phones. Actual Quick Charge (Qualcomm) chargers will say it on them somewhere. The problem is that there are a lot of other chargers that also use faster charging technology which may be called PowerIQ, or Fast Charge, or something else. Hard to tell if they would have issues too.

What you are looking for is a plain 5V USB power supply...primarily designed to power things not charge them fast. If it says 5V and 1 Amp or more you will probably be fine.

BUT, you are absolutely right. It appears that SMSL (at least their marketing department) did not know the Sanskrit 10th requires a wall wart for USB to work right. If they had known it, including one in the box would have been cheap and allowed customers to buy the 10th and not worry. Let's see if they do that at some point going forward.

That said, if you are considering buying a 10th I am sure people here can point you to quality/cheap ones that will work. If you are like me, it would mean going to my electronic gizmos drawer and picking one I already own that is 1 Amp or more.

 

[SMSL-Mandy]

Thanks for amir's help.
Thank you for your patience.

 

[Hugo9000]

Thanks very much, @GGroch , and thanks again @amirm for the original test and the followup!

 

[folzag]

It's actually a very good DAC candidate to test the Wyrd

2nd-ed!

... seemed obvious we wanted to test the Wyrd, not the Sanskrit. (I was going to make the same comment until I saw it had arleady been made.) If the Wyrd can't solve this obvious use-case, then it really, REALLY is Schiit.

 

[GGroch]

2nd-ed!

... seemed obvious we wanted to test the Wyrd, not the Sanskrit. (I was going to make the same comment until I saw it had already been made.).........

How would you hook up the Wyrd to the Sanskit 10th? Would you need 2 of them?

As I understand it the Wryd has 2 functions...to "decrapify" the USB Signal (this would require connection to to the In1/Power Micro USb) but also to
clear up "noisy USB power, or USB port power management" with a linear power supply (connects to the "Aux Power)?

It seems lack of power is the primary problem with the 10th's USB input, even when Amir used his higher power USB 3 output. It does not seem likely the single USB 2 output on the Wyrd would handle it by itself.

 

[folzag]

How would you hook up the Wyrd to the Sanskit 10th? Would you need 2 of them?

No. I would expect the Wyrd to supply the required extra power through the same USB input as the signal.

... even when Amir used his higher power USB 3 output

Hmmm. OK, it didn't occur to me the device required more power than can be delivered by a single USB input. Is that really the case? I thought it needed more current than his hub could supply, not that the current was beyond that allowed for a single USB input.

 

[folzag]

OK, I find this super interesting... I wanted to see the back of the unit so I did a quick search and this YouTube review was the second or third hit. At 1:10 he describes the two USB ports as "so, if you're not going to be using the USB for signal input (ie. use S/PDIF), you're going to have to hook power to this upper USB port." Heh. Intuitive, rational, and, yet, exactly backwards.

And sure enough, his review of the sound, which starts at 1:23 matches about one would expect given what we now know. Always nice when the objective measurements can anticipate the subjective results, eh?

 

[Krunok]

The leftmost port is a ac in. so it doesn't use usb power at all.

That was a joke on my account.

 

[amirm]

I am not defending the Google dongle here. I am a Google software engineer but I use no Google hardware products at all. I neither design nor has any relationship with hardware products the company is building.

I don't think your company is building the dongle anyway. You should check. Most likely it was farmed out to an ODM to design, build and get it manufactured. Where the company failed was in not setting standards for the performance. It was a checklist item and a checklist product was received.

 

[Sangram]

Whereas I agree that in this case the manufacturer should have been explicitly clear about the need for a power source when using USB as well - or offer such a supply for sale - the vagaries of depending on USB power are many and well known.

The USB ports of different computers/motherboards are powered differently. Not all downstream equipment will be able to operate correctly on all upstream ports. For example, when we order USB fuses you will have a variety of current and surge ratings, even if the overall spec is still 500mA. A fuse with zero surge rating, for example, will have a very high resistance and will sag above 50% of current draw. Overall power budgets dictate the choice of fuses, and the end-user has no control over the quality of USB port power.

One of the reasons the unit did not operate correctly when connected to USB 3.0 port was the lack of signalling. The PC assumes it is a USB 2.0 device, and does not turn the port into USB 3.0 mode. The additional power pins on the USB 3.0 A host port do not have corresponding contacts on the micro-USB cable, so you do not get the benefit of the additional power either.

Most equipment using XMOS receivers will draw the power for the XMOS from the USB port, but power all other circuitry off other power sources (where available). There is also the issue of the USB cable, some are built with thinner wire and may have significant voltage drop. For example it seems highly unlikely that the unit will operate correctly when connected to phone using OTG cable, as the phone's port will never supply that much power.

All equipment using USB power will give different results depending on the test situation. It might be a good idea to test all USB-connected devices with an external supply when such a possibility exists. Whereas I understand the need for test protocol, one of the founding principles is the need to eliminate variables. The USB port performance of a PC and cable system is a variable and cannot be assumed constant, which means the results may vary by user configuration, motherboard capability, and so on. You could consider eliminating this variable.

BTW I purchased this unit before seeing any reviews, and find it excellent at the price. Have been using with a simple linear supply from day 1, and I love it. Much better than the DX3 Pro which I also purchased together with this.

 

[Krunok]

Much better than the DX3 Pro which I also purchased together with this.

In what way "much better"?