SMSL DO400 Fully Balanced Audio Decoder & Headphone Amplifier

[Roland68]

Addition to the family
SMSL DL400

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View attachment 405145

Wouldn't the DL400 thread be the right place?

 

[iTuner]

I has no intention of discussing here the new DAC from SMSL. I just wanted to note that this is already the fourth device on the same hardware.
I am happy with my DO 400

 

[audiojack]

hello. i have the DO400 and i love it so far, i pair it the Airpulse A300 speakers using XL:R and seem the i have some clipping higher than -1.0db
so i use -2.0 to be sure and sound clean and nice!
i suppose the speakers dont support 5V but on Topping D90SE i was used in the past there a setting to set the 4v and 5v by user

the quick question is: is the -2.0db the right volume to get the proper 4V or is it higher like -1.5db?
thank you in advance!

Does your Airpulse A300 sound noticeably different with the DO400 ob the XLR input?

I tried the SMSL D6S external DAC on the A300 (active speaker) XLR input and to my ears it sounded basically identical?! And what surprises me most is that the treble and bass knobs on the back of the speakers still function in XLR mode? Because of these findings it seems like the A300 XLR input signal still passes through the internal A300 DAC and is still processed by the active speakers?

 

[Roland68]

Does your Airpulse A300 sound noticeably different with the DO400 ob the XLR input?

I tried the SMSL D6S external DAC on the A300 (active speaker) XLR input and to my ears it sounded basically identical?! And what surprises me most is that the treble and bass knobs on the back of the speakers still function in XLR mode? Because of these findings it seems like the A300 XLR input signal still passes through the internal A300 DAC and is still processed by the active speakers?

The Airpulse A300 has a digital crossover (DSP), so the signal is always processed digitally, regardless of whether the input is analog or digital. A DAC connected upstream is therefore unnecessary.

 

[FredyR4zox]

Would you recommend DO400 or DO300EX?

 

[Roland68]

Would you recommend DO400 or DO300EX?

Both work perfectly for me and are recommended.
The DO300EX has a smaller HPA and is only single ended with about 1 watt at 32 ohms, while the HPA in the DO400 is balanced and has about 4 watts of power.
Also take a look at the Loxjie D60, identical to the DO400 but with a newer display and better indicators.

 

[FredyR4zox]

Both work perfectly for me and are recommended.
The DO300EX has a smaller HPA and is only single ended with about 1 watt at 32 ohms, while the HPA in the DO400 is balanced and has about 4 watts of power.
Also take a look at the Loxjie D60, identical to the DO400 but with a newer display and better indicators.

The DO300EX also has balanced HPA. 4.4mm balanced and 6.35mm single-ended
I'm going to use it with the Fiio FT1, so I think that in terms of power the DO300EX will be able to handle it.
Which one do you like the sound the most?

 

[Roland68]

The DO300EX also has balanced HPA. 4.4mm balanced and 6.35mm single-ended
I'm going to use it with the Fiio FT1, so I think that in terms of power the DO300EX will be able to handle it.
Which one do you like the sound the most?

The DO300EX definitely only has one SE HPA, the 4.4mm connection doesn't change that, it's also only wired as SE. There's only a single TPA6120A2 with 2 channels installed, so balanced is technically impossible. The DO400 and D60 each have 4 x TPA6120A2 installed, hence the higher power.
If you have a power-hungry HP, you'll need an additional HPA with the DO300EX.

You won't be able to tell the difference between these devices in terms of sound in a blind test, the DO300EX might be a bit worse with the HPA.

In my opinion, the output stage on the DO400 and D60 is better developed and constructed, on the DO300EX it seems to just be the standard circuit.

But you have to make the decision.

 

[iTuner]

Would you recommend DO400 or DO300EX?

The headphone amplifier in the DO300EX is much simpler. This is an unbalanced amplifier with a 1xTPA6120.
Balanced amplifier is not about power and efficiency. Balanced amplifier has improved technical parameters. You will get additional Power as a bonus.

 

[FredyR4zox]

Thank you @Roland68 and @iTuner for your recommendations!
I don't need too much power because my headphones are not hard to drive, and I will be only using headphones.
I think I'm going to go with the DO400, and not with DO300EX or RAW-MDA1.

 

[guigui]

Has anyone tried this, the FiiO K9 AKM and the Loxjie D60 that @Roland68 mentioned?

 

[Roland68]

Has anyone tried this, the FiiO K9 AKM and the Loxjie D60 that @Roland68 mentioned?

I can only tell you that a friend of mine had the FiiO K9 AKM and SMSL DO400 (identical to Loxjie D60, D40 Pro and DL400) at home to test and he kept the DO400.
In terms of the DAC, there was probably no difference, but the HPA in the DO400 (German D60) is significantly more powerful (it was enough for him for the Hifiman HE6se V2) and more detailed, more concise and more grippy, even in quiet passages (his words ;o).
I can understand that, because I didn't particularly like most THX HPAs either, but I really like the DO400 with its HPA.

Originally he actually wanted the Fiio because he liked it better (visually), and to be honest I did too, but.... Oh well
If you have the chance, try both.

 

[guigui]

I can only tell you that a friend of mine had the FiiO K9 AKM and SMSL DO400 (identical to Loxjie D60, D40 Pro and DL400) at home to test and he kept the DO400.
In terms of the DAC, there was probably no difference, but the HPA in the DO400 (German D60) is significantly more powerful (it was enough for him for the Hifiman HE6se V2) and more detailed, more concise and more grippy, even in quiet passages (his words ;o).
I can understand that, because I didn't particularly like most THX HPAs either, but I really like the DO400 with its HPA.

Originally he actually wanted the Fiio because he liked it better (visually), and to be honest I did too, but.... Oh well
If you have the chance, try both.

Thanks for your answer!

What exactly do you dislike about the THX HPAs?

 

[Roland68]

Thanks for your answer!

What exactly do you dislike about the THX HPAs?

A bit of transparency and authenticity in acoustic instruments, especially in jazz. But that's complaining at a very high level. I've just been spoiled by too many live concerts.
But I've only heard the usual suspects, Monoprice, Drop, SMSL, etc. Unfortunately not the benchmark.
The SMSL SH-9, on the other hand, is one of the best HPAs I've heard so far.

 

[guigui]

A bit of transparency and authenticity in acoustic instruments, especially in jazz. But that's complaining at a very high level. I've just been spoiled by too many live concerts.
But I've only heard the usual suspects, Monoprice, Drop, SMSL, etc. Unfortunately not the benchmark.
The SMSL SH-9, on the other hand, is one of the best HPAs I've heard so far.

Wait, I don't know if I get it. Do you think it's too transparent or not as much as you wanted?

 

[Roland68]

Wait, I don't know if I get it. Do you think it's too transparent or not as much as you wanted?

A device can't be too transparent because it can only reproduce what is contained in the recording.
Most THX devices didn't have the transparency I would have expected, but as I said, that's complaining at a high level. It's not a world of difference and not something you would hear in a quick comparison.

 

[guigui]

A device can't be too transparent because it can only reproduce what is contained in the recording.
Most THX devices didn't have the transparency I would have expected, but as I said, that's complaining at a high level. It's not a world of difference and not something you would hear in a quick comparison.

I understand.

Another person suggested getting the Topping E70/L70 stack, but I don't want to bother you anymore. I'm leaning towards the DO400 anyway.

Thanks a lot for the help! I get too obsessed about my choices, specially when the options are too close to each other, because I go even deeper in nitpicking. For example, I think that the build quality of the FiiO gears I've seen are much better than the SMSL gears I've seen, even the circuitry. I know that those things won't make much difference, but I can't avoid thinking about them.

Anyway, I digress. Again, thanks a lot, man!

 

[RedEyeNinja]

I am very happy with the DO400 as an AIO and it eased my entry into the headphone world. Wanting more power, I've tried pairing the DO400 with a SP400... And I'm now happy pairing it with a H400. This is by no means any "endgame" stack but I like clarity, or as some call it analytical-ness/blandness, of the SMSL offerings, while I do my own eq'ing. IMO, this kinda of clean, uncoloured sound provides a good basis for trying out various equipment reliably... Meaning if something sounds off, I know it's not from the house signature of the dac or amp.

Don't get me wrong... We all deserve some RME ADI-2 DAC Pro sending signal to a LAiV HP2A... Lol

 

[nanook]

Balanced amplifier is not about power and efficiency. Balanced amplifier has improved technical parameters.

I disagree on this.

Balanced configuration for headphones (and amplifiers for speakers) mainly is about output power into higher load impedances.
The usual integrated circuits operate at +/-15V and they withstand something like +/-22V short term. Assuming an internal supply of +/-15V (often it's just +/-12V), you can have best case ca. 10Vrms with a single-ended stage. This means ca. 167mW max. at 600 Ohms.
With a balanced driver circuit you get 2x the voltage and thus 4x the power.

Apart from this the single-ended output stage only has advantages.
- it operates into the nominal load impedance compared to the balanced output stage where each branch sees 1/2 of the nominal load impedance.
- there's only 1x the output impedance of the driver stage compared to 2x for the balanced output stage

The most important thing about "balanced headphone" is the wiring of the headphone cable. In single ended configuration both capsules may share the same return wire (Gnd = sleeve) depending on the cable. This will reduce crosstalk, especially for low impedance drivers in combination with cheap cables with tiny cross-sections.

Don't mix this up with balanced signal connection like XLR and TRS. Here the important term is "balanced source impedance". Having the same source impedance on both legs has potential advantages for some situations of interference. - It does as well not need a balanced driver for this. Connecting Pin 3 to Gnd via a resistor serves the purpose equally well.
In case you need the higher output voltage, the balanced output stage is the solution.

 

[Roland68]

Balanced amplifier is not about power and efficiency. Balanced amplifier has improved technical parameters. You will get additional Power as a bonus.

As @nanook has already written, you are wrong for many reasons.
Another important point is that with symmetrical amplifiers, the noise from both power amplifiers in the respective channel is added together.

There is no difference in performance either, as both SE and symmetrical amplifiers can be built in all performance classes.

From practice, I can say that I have experienced several times that with two amplifiers of the same design, the SE version had a slight advantage and sounded slightly more transparent and cleaner. When it comes to differences, I am not talking about worlds, but about nuances.
In other cases, the symmetrical and SE versions of the amplifiers sounded absolutely the same and could not be distinguished.
An example of this is the SMSL SH-9 and SP400, which are built the same, but I would always give preference to the SH-9 if the performance is sufficient and no preamplifier output is required.