Lavaudio DS600 Review (Stereo DAC)

[JIW]

Ah, the truth comes out! Someone just tapped the RCA outs and brought it to the front and called it done. This is wrong as the RCA out typically has high impedance in the order of 100 ohm we see here. That high impedance causes a ton of power loss as we see in the 33 ohm test.

Have you measured the output impedance? It's not in the review. According to the manufacturer, it seems to be 10 Ohm. However, it is not specified for which output.

Source: https://1mii.com/wp-content/uploads/2020/12/DS600-Manual-12.24.pdf

Further, the measured power at 300 ohm of 13.26 mW corresponds to the line-out level - 1.994 V for channel 1 giving 13.25 mW for a 300 ohm load - suggesting that the output impedance is near zero. A 10 ohm output impedance would instead give 12.4 mW.

The power loss at 33 ohm being entirely due to the output impedance would require the output impedance to be about 133 ohm. Thus, the output impedance must be highly load-dependent to allow for the measured power at 300 ohm at the line-out level.

For the 33 ohm load, the current corresponding to the maximum power is about 15 mA. At 300 ohm only about 4.7 mA is required to reach maximum power. Since there is no rapid rise in distortion after maximum power, which is reached at only about 25% of the line-out level, there seems to some load-based limiting before the output stage - or the output impedance is indeed highly load-dependent.

Thus, if it were the case that the output from the RCA and the headphone output are the same, the output impedance must be the same on both and their power and distortion must be the same for the same load.

Inasmuch as you have not so far, could you thus not only determine the output impedance of the headphone output but also that of the RCA output and further, determine the RCA-outputs power and distortion at 33 ohm and possibly also at 300 ohm?

 

[Ron Texas]

It's getting hard to find a DAC which does not measure well. The category is mature. It's interesting that the headphone section is a bust. I would stick with Topping because I have a D30 and a D3x pro and they did not break.

 

[JIW]

Here are some measurements published by the manufacturer. Looks like they have some Audio-Precision analyser.

First, signal-to-noise ratio. About 3 dB higher. B-weighted, however.

Next, SMPTE IMD Level sweep - 60 Hz and 7kHz at 4-to-1 ratio, so the same as Amir. About the same but hump at 2-3 dB lower generator level and less IMD at above -5 dBFS generator level.

Lastly, THD and noise at 1 kHz at 0 dBFS. Comparable to Amir's dashboard. Level seems to be around 2 V RMS so 1u = -126 dBr. Less 2nd to 4th harmonic but more 5th and higher and seemingly only odd harmonics. SINAD is -113.152 dB for channel 1 and -112.728 dB for channel 2.

Source: https://1mii.com/product-item/lavaudio-ds600-hifi-decoder/

 

[technoian]

Why would any manufacturer choose to compete with the Topping D50S? Even if you could match the performance (which they make a good job of here) you are still going to have to undercut the D50s on price or include extra features (such as the headphone output). When those features turn out to be worthless any advantage you may have had is lost.

 

[Veri]

Why would any manufacturer choose to compete with the Topping D50S? Even if you could match the performance (which they make a good job of here) you are still going to have to undercut the D50s on price or include extra features (such as the headphone output). When those features turn out to be worthless any advantage you may have had is lost.

They are selling for $200 mark. I'm betting that they make decent profit from that MSRP, and consumers might believe they are buying a D50/D50s, while it is a knock-off. Not a terrible one mind you, but still.

 

[JIW]

[...] They do have an AP console snapshot. Seems this is becoming quite the thing. They are however claiming significantly better numbers and at lower voltage out.
[...]

I have posted the measurements in a prior post. I skimmed the thread on first reading and missed your post about it. Anyways, how do see their numbers being significantly better and the voltages being lower? I find them overall comparable.

 

[dinglehoser]

They are selling for $200 mark. I'm betting that they make decent profit from that MSRP, and consumers might believe they are buying a D50/D50s, while it is a knock-off. Not a terrible one mind you, but still.

Agreed. By making a copy (and assuming that's what this is, and not a white box Topping rebrand), they don't have to bake the cost of R&D into their price. Topping's already taken the hit - the shyster can just ride on their coattails. Easy money.

 

[sarumbear]

[...]When those features turn out to be worthless any advantage you may have had is lost.

You are assuming the average buyer will notice it. In Amazon tables it will show as extra function at a lower price and people will buy. This is why what @amirm is doing is priceless for the educated buyer.

 

[Beershaun]

It seems like this should get a "not recommended" due to the improper headphone amplifier implementation. Regardless of whether or not it's a licensed product. The engineering on this product for a key feature, the headphone amplifier, is poor/incorrect. I think it's okay to say "this is not recommended due to incorrect/poor implementation of the headphone amplifier and if you understand this fact and still want to use it for a stereo DAC, this is a fine stereo DAC." I think it's okay for @amirm to take a stronger stance on the engineering quality since that is his "stock in trade."

 

[amirm]

Have you measured the output impedance? It's not in the review.

I did. I thought I put it on the graph but post the version without. I mentioned in text that it is 100 ohm, not 10 ohm. This was the proof that it was tapped out of the RCA Out:

"Ah, the truth comes out! Someone just tapped the RCA outs and brought it to the front and called it done. This is wrong as the RCA out typically has high impedance in the order of 100 ohm we see here. "

I recall the output dropping from 1 volt unloaded to just 0.25 volts which indicates a large output impedance.

 

[amirm]

It seems like this should get a "not recommended" due to the improper headphone amplifier implementation.

That would indicate its DAC is not competitive either and I can't go there. The hp amp is a throw-away feature and I called it that. It doesn't get in the way of using the DAC properly.

 

[Helicopter]

Regardless of the circuit or performance, the appearance is enough of a ripoff that I would consider this an unlicensed copy unless @JohnYang1997 unexpectedly disagrees.

 

[JIW]

I did. I thought I put it on the graph but post the version without. I mentioned in text that it is 100 ohm, not 10 ohm. This was the proof that it was tapped out of the RCA Out:

"Ah, the truth comes out! Someone just tapped the RCA outs and brought it to the front and called it done. This is wrong as the RCA out typically has high impedance in the order of 100 ohm we see here. "

I recall the output dropping from 1 volt unloaded to just 0.25 volts which indicates a large output impedance.

I read that bit of text as just indicating the magnitude of output impedances typical of line-outs. For a 33 ohm load, the 75% voltage decrease indeed corresponds to a 100 ohm load in series.

Still, curious how at 300 ohm, there is seemingly no effect. The voltage across the load should be reduced by 25% and the power thus be 43.75% lower. Given the significant expected difference, could you measure the output impedance with the 300 ohm load?

 

[PeteL]

But why oh why do we have yet another device that thinks that sample rate is the most important thing to display?


The digram describing the remote control show two keys as "invalid". That is never a good look on a product.

.

By more important do you mean the size of the digit compared to the input and format? What do you feel would be more important to display?
If it is anything like the e30 from topping, you get SR on the display in what they call pure dac mode (fixed volume) and it shows level in `preamp mode (variable). My e30 also have invalid keys, but actually may be worst, I would rather have them labeled invalid, but they are marked "line out" and "M"... go figure...

 

[Francis Vaughan]

Anyways, how do see their numbers being significantly better and the voltages being lower? I find them overall comparable.

Not sure. I must have misread something. Agree, they are pretty comparable.

 

[Newman]

Back panel is what you expect:

View attachment 104258

For DACs (and preamps) that, as above, have a PSU input port that opens up the real-life possibility of being powered from various devices by owners, I would see value in the review including a PSRR measurement.

What say you, Amir?

 

[amirm]

For DACs (and preamps) that, as above, have a PSU input port that opens up the real-life possibility of being powered from various devices by owners, I would see value in the review including a PSRR measurement.

What say you, Amir?

Waste of time. I tested the same on Topping D50 and it simply makes no difference how you power it. FYI I tested this DAC with the USB hub in my monitor powering it.

 

[Newman]

Waste of time.

I have an SMSL M3 DAC (several, actually), and I absolutely guarantee you that highly objectionable noises come straight out of the loudspeakers if I power them from certain USB PSU’s, and not from others.

Waste of time?

 

[JohnYang1997]

I have an SMSL M3 DAC (several, actually), and I absolutely guarantee you that highly objectionable noises come straight out of the loudspeakers if I power them from certain USB PSU’s, and not from others.

Waste of time?

That's called ground loop.

 

[Newman]

Oh? Then tell me what it sounds like.