AIYIMA D03 class D amplifier "Subjective review"

[mhardy6647]

 

[dr0ss]

That's lovely.

My father sold transistor radios back in those days, I loved to open them and admire the innards.

Back on topic, the only other amp I can find using the TAS5624 power amp is the highly regarded QLS690. That one has very high quality parts in the implementation, and I would guess at the very least its ADC stage will leave the D03 in the dust, but this is pretty good company.

 

[Toku]

How well-behaved is the D03 switched from a master switch? In other words, if you unplug it then plug it back in, does it retain settings and start from where it left off?

This amp sounds like the TI TAS5624 evaluation module together with their USB input board 3, at a fraction of the price. It isn't exactly latest and greatest technology (the IC is from 8 years ago), but could be good enough for most human ears.

​

I have been using AYIMA D03 for about 3 months, and D03 remembers the setting information even if the power line is completely turned off. Therefore, the status does not change even if the entire system is turned ON / OFF with the master switch. Also, at this time, pop noise does not appear.
I think the D03 chip is old, but it's not old. The same is true for the popular TI -TPA3255.
The sound quality of the digital input of the D03 is very good, and it is not inferior to the latest DA-9, AO200, A20a, PA03, etc. The sound quality is excellent considering the price.
However, the sound of the analog input of RCA is not good. I have reported this issue to AIYIMA but no further improvement information. D03 is a full digital input amplifier. I can recommend D03 to many people if it is used on the premise of digital connection.
If you have any questions about AIYIMA D03, please ask me.

 

[Toku]

I can tell the age just by looking at the parts of the printed circuit board. I was surprised that PWM amplifiers had been commercialized since this era.
I also stock transistors of this era in my parts box.

 

[dr0ss]

However, the sound of the analog input of RCA is not good. I have reported this issue to AIYIMA but no further improvement information.

I had seen you mention this either earlier in this thread or on another thread, but not so strongly. I suppose this is because of the AD conversion , in which case it might not be repairable without a major overhaul. It is too bad if true.

Thanks for the information on the power-on. This is something that is always a question when the controls are electronic.

 

[mhardy6647]

I can tell the age just by looking at the parts of the printed circuit board. I was surprised that PWM amplifiers had been commercialized since this era.
I also stock transistors of this era in my parts box.

I've had this perverse desire to put together one of these archaeo-PWM amplifiers since I first learned of them a few years back.

 

[Schlippwhip68]

Oof. That solitary 3300uf cap isn't going to be enough. Wow. Are other Aiyima amps built this way?

Can you go into detail as to why this might be a problem?

 

[DanielT]

It's a toy,

Toys are fun

I present to you the brand new Aiyima D03 Class D amplifier

View attachment 146822

AIYIMA D03
After several listening experiences, with different amplifiers, by class and by brand, today, after having extensively tested various electronics, even in class D, I focus on the new amplifier from AIYIMA (Chinese manufacturer), which produced the D03

It is a class D of 670 grams, not bulky at all.

Lightweight and easy to place in your usual listening environment, it won't disappoint you.

Indeed, I was thrilled when I realized how much quality and power such an object releases.

In fact, I can say that, having little space in my house, with the D03 I solved the problem.

It is built solidly.

But let's immediately consider what we find inside the packaging.

It contains our device, an infrared remote control, for convenient control of the main functions (adjusting the input / volume / bass / treble / mute mode), a power adapter (DC32V 5A), a USB cable and a cable optical.

View attachment 146880

A very respectable endowment! From the remote control, slim and functional, it is possible to juggle all the commands that we find on the display.

But let's try to proceed in order, because this little one really deserves it: let's talk about the back, then the front and my listening experiences.

Later this amplifier, which not only has the role of amplifying and that's it, but also takes on the role of digital to analogue decoder (DAC); I was saying, this AIYIMA amp-DAC offers from left to right: a power input (size 5.5 - 2.5 mm, European or USA section) from DC 24-36 v. A 32v 5 amp power supply is recommended.

Then we have the output sockets for the passive speakers (SPEAKER OUT), usually in plastic, which accept the stripped cable, forks or the classic bananas; a speaker out dedicated (hear) to the SUBWOOFER, which, attention !, must be active. Let's move further to the left and our AIYIMA D03 features the classic RCA analog inputs; therefore, still in the audio-in section, a complete range of inputs, now canonical, but not always so integrated in a single device: coaxial input, input for Bluetooth via a special and dedicated antenna (supplied in the package), the OPT (optical) digital input and PC-USB input.

All very neat and complete.

I mean, what can we connect to this D03? Practically, if not all, really a lot: PC, Laptop, Tablet, Smartphone, an analogue and digital source (DVD, CD, etc.), an external DAC.

View attachment 146881

Let's turn this amplifier around, so that we have its front part in front of us. All very basic and well done, very clear.
On the left, the Switch button and, then, next to it, the INPUT selection button.

Exactly in the center, a pleasant display, with blue quartz, explaining the selected functions, with an indicator of entry in selection (clearly highlighted by symbols or letters), the volume from 0 to 99 and the indication of the KHZ of the DAC. Let's not forget, far right, the volume knob, well made and rather well scaled, to testify, as I said, the good build quality of the object.

View attachment 146882

Bluetooth 5.0 chip: QCC3034 supports: ACC, SBC, aptX, aptX-LL, APTX-HD.

Optimal! The sampling frequency of the digital sector, via internal DAC is 24bit / 192khz and does not go beyond.

The encoding is not of the highest quality and, during my listening, I preferred to use a higher performing external DAC and the results were remarkable.

The operating systems supported by the internal DAC (Chip CS8422) are the following: XP / Vista7 / 8/10 / Max OS / MAC / Linux / Mobile OTG. Under the hood we have a Texas Instruments processor, in 8-channel HD audio TAS5548 + a TAS5624, from the same house.

AIYIMA, I remember, for a long time, uses similar chips, from Texas Instruments, of great quality.

Finally, the DRV603, which is a 3V pop-free stereo line driver, for gain control and adjustment.
93 are the DB of the signal-to-noise ratio, frequency response 20-20Khz (± 1.25db); input sensitivity: 0.775V; the gain of the tone (treble and bass): ± 14, which works very well; the output level of the Subwoofer: 2.1, the total harmonic distortion is 0.001% (1kHz 1w) and the variable impedance of 4-8Ω. It means that you can couple a lot of different speakers and with various impedances.

If you follow the recommended power supply, even with high summer temperatures and moderately intense use, the appliance heats up very little.

Let's now turn to my listening experience.

View attachment 146878

Basically I connected a digital source (PC), with Foobar2000 software, to the D03, via DAC Topping D10s and Q ACOUSTIC 3050i speakers, which are floor standing.

I also own two other high-cost class AB and D amplifiers, branded Onix A55 MK1 and Arcam A29.

What can I tell you? This AIYIMA D03 surprised me.

I also owned an amplifier like AIYIMA A07, but the D03 sounds much more powerful, never clipping, with a detailed scene worthy of the 3255 chip, very sweet on the highs and nice strong lows, but never intrusive.

Personal taste comes into play here, but I guarantee you that there is no comparison with my previous AB and D classes, with respect to which I always noticed some flaws: little power, no bass and annoying details in the mid-high range.

My Q ACOUSTICs now do their duty and are truly enhanced by the AIYIMA D03.

For me it seems much better than aiyima a07 and it also sounds with much more power and pilot better certain types of speakers and on 8 ohm it seems to me that it has a power of 55 watt rms, because I put it in comparison with my Onix A55 MK1 in class A/B

At this point I recommend it.

Nice. Thanks for your summary! Good work

How do you experience the build quality? Solid terminals, connetctions?

Is it possible to change the brightness of the display?

I see Bluetooth. Works properly? Hard to get started? Plug and play? Is the reception strength good?

Then this with how you experience the sound. Of course, it is subjective, but everyone understands that this is the case. If you are satisfied and happy with that sound, it's fine.

One that might be nice to have in the kitchen. Or in the bedroom. Looks smooth. In that case (kitchen/bedroom), I do not care so much about the sound quality itself. To get a good sound then I instead put the gunpowder on the main system in the living room. However, sensible function that works well is important.

It is possible that AIYIMA D03 performs well, it will be interesting to see if Amir will test it.However, I doubt the performance regarding higher frequencies regarding such, after all, relatively low-power class d amplifier is that good (although it may be best to touch that wasp nest, regarding that issue )

What was the price of a AIYIMA D03?Or what is the best price you can get, any tips?

Edit:
In addition, as others pointed out in the thread weigh together price, functionality and performance. Then AIYIMA D03 may very well be a good choice.

 

[Schlippwhip68]

Toys are fun

Nice. Thanks for your summary! Good work

How do you experience the build quality? Solid terminals, connetctions?

Is it possible to change the brightness of the display?

I see Bluetooth. Works properly? Hard to get started? Plug and play? Is the reception strength good?

Then this with how you experience the sound. Of course, it is subjective, but everyone understands that this is the case. If you are satisfied and happy with that sound, it's fine.

One that might be nice to have in the kitchen. Or in the bedroom. Looks smooth. In that case (kitchen/bedroom), I do not care so much about the sound quality itself. To get a good sound then I instead put the gunpowder on the main system in the living room. However, sensible function that works well is important.

It is possible that AIYIMA D03 performs well, it will be interesting to see if Amir will test it.However, I doubt the performance regarding higher frequencies regarding such, after all, relatively low-power class d amplifier is that good (although it may be best to touch that wasp nest, regarding that issue )

What was the price of a AIYIMA D03?Or what is the best price you can get, any tips?

Edit:
In addition, as others pointed out in the thread weigh together price, functionality and performance. Then AIYIMA D03 may very well be a good choice.

I've just ordered a D03 from YIMAglobal on Aliexpress website. Cost £106 (UK) with the PSU. Price will be less without the PSU but trying to find a 32v 5A power supply with a specific connection for this unit is not easy here in the UK so the first thing I would advise is include the PSU regardless!
I already have a modded Aiyima A04 which I am running with the LM4562NA op amps installed and I am quite happy with the overall sound, its detailed enough , better instrument separation than the NE5532 op amps with tighter and better controlled bass. The vocals and midrange are clearer too. Now, apparently the D03 sounds better than the A07 with a bigger and fuller sound so if that is the case as it well might be then i dont think that the D03 will be a disappointment at all.
I do however have a little concern about the apparent lesser quality of the RCA connection on the D03 as I would like to run an Topping E30 through the RCA connections and so hoping that the signal is not going to be impaired by a possibly poor implementation of the analogue inputs. On an up note, Robertospeed did say that with the external DAC connected, in this case the Topping D10s, that the sound was, and I quote,' remarkable' and I am presuming as i have only glanced at the article, that he did connect the D10s via the RCA. Also Youtuber 'CheapAudioMan' said that the D03 is a very acceptable small amp that little to no tuning and was pleased with the sound. It was his recommendation that gave me cause to buy the A04, of which I am glad I did. I also bought the Sabaj A10A but found I was more comfortable with the sound of the Aiyima A04. I would expect the build quality of the D03 will be on a par with both the A04 and A07 which are both solid and will stand up to everyday use. I will have my D03 in a few weeks but if you live in the UK then only the D05 is readily available here.
If anybody can mark out the clear benefits of the D05 over the D03 then that would be helpful to many here.
Going off topic slightly, I am considering a discrete op amp for the A07, just for the fun of it!

 

[bravomail]

However, the AUX input is not good. Compared to digital input, the sound quality is much more relaxed and quiet.

Hi Toku. Thx for impressions! Did u test AUX with low input volume? It sounds like u did. Set the volume on PC to 100% and set DAC to DAC mode (2V) or maximum Pre mode. And sampling frequency to 44.1 or 48KHz.

 

[dr0ss]

The sound quality of the digital input of the D03 is very good, and it is not inferior to the latest DA-9, AO200, A20a, PA03, etc. The sound quality is excellent considering the price.

Since you seem to like trying these little amps, I wonder, have you tried the D01? It seems to have the same feature set as the D03, but without the LED display (a likely cause of early failure), and with even older tech chips (though its TPA3221 was once highly regarded). I can't find any discussion of it on ASR or even DIYaudio.

 

[Bushellj]

I've just ordered a D03 from YIMAglobal on Aliexpress website. Cost £106 (UK) with the PSU. Price will be less without the PSU but trying to find a 32v 5A power supply with a specific connection for this unit is not easy here in the UK so the first thing I would advise is include the PSU regardless!
I already have a modded Aiyima A04 which I am running with the LM4562NA op amps installed and I am quite happy with the overall sound, its detailed enough , better instrument separation than the NE5532 op amps with tighter and better controlled bass. The vocals and midrange are clearer too. Now, apparently the D03 sounds better than the A07 with a bigger and fuller sound so if that is the case as it well might be then i dont think that the D03 will be a disappointment at all.
I do however have a little concern about the apparent lesser quality of the RCA connection on the D03 as I would like to run an Topping E30 through the RCA connections and so hoping that the signal is not going to be impaired by a possibly poor implementation of the analogue inputs. On an up note, Robertospeed did say that with the external DAC connected, in this case the Topping D10s, that the sound was, and I quote,' remarkable' and I am presuming as i have only glanced at the article, that he did connect the D10s via the RCA. Also Youtuber 'CheapAudioMan' said that the D03 is a very acceptable small amp that little to no tuning and was pleased with the sound. It was his recommendation that gave me cause to buy the A04, of which I am glad I did. I also bought the Sabaj A10A but found I was more comfortable with the sound of the Aiyima A04. I would expect the build quality of the D03 will be on a par with both the A04 and A07 which are both solid and will stand up to everyday use. I will have my D03 in a few weeks but if you live in the UK then only the D05 is readily available here.
If anybody can mark out the clear benefits of the D05 over the D03 then that would be helpful to many here.
Going off topic slightly, I am considering a discrete op amp for the A07, just for the fun of it!

I have also just ordered the Aiyima D03 having owned Aiyima A04 and Aiyima A07 for the last year or so. Very please with both the A04 and A07 but wanted something with an optical input and remote control to use with the TV as part of the AV System. The D03 seemed to be the next natural step and almost unbeaten at the price. I will continue to use the Mean Well external Power Supplies (LRS-200-24) as my first choice as these appear to work well with all my Class D amplifiers.

The D03 appears to be a more recent product than the D05 whose chipset is now obsolete according the Texas Instruments.

The only downside that I can see with the D03 is the choice of DAC used for the analog input which might be a bit basic - BUT then you wouldn’t be buying the D03 if you weren’t going to be using the Digital inputs !! If you want to use Analogue inputs then the A04 or A07 would be a better choice (as long as you don’t need a remote).

Keeping in mind that Class D amplifiers are basically Analogue devices the choices may seem strange !!

Thank you to Toku for his earlier review which helped me make the decision !!

 

[Walter]

I can recommend D03 to many people if it is used on the premise of digital connection.
If you have any questions about AIYIMA D03, please ask me.

OK, I will. (And anyone else who has used the D03 is of course welcome to reply, as well.)

1. Does it have a 'loudness' setting, to increase the bass and treble for low volume listening?
2. Based on the chip's specs, it would seem that a 36v 9.7a power supply like the Mean Well LRS-350-36 would be a better choice than the one Aiyima sells. Do you agree? Does the D03 get hot when using the supplied 32v 5a PSU?
3. In your personal, subjective opinion, is the sound quality using the digital inputs as good as the DA-9, or the A04/A07 combined with a good DAC such as the Sanskrit 10 MkII?
4. Have you tried both the USB and optical inputs, and if so, was the sound the same?

 

[Toku]

OK, I will. (And anyone else who has used the D03 is of course welcome to reply, as well.)

1. Does it have a 'loudness' setting, to increase the bass and treble for low volume listening?
2. Based on the chip's specs, it would seem that a 36v 9.7a power supply like the Mean Well LRS-350-36 would be a better choice than the one Aiyima sells. Do you agree? Does the D03 get hot when using the supplied 32v 5a PSU?
3. In your personal, subjective opinion, is the sound quality using the digital inputs as good as the DA-9, or the A04/A07 combined with a good DAC such as the Sanskrit 10 MkII?
4. Have you tried both the USB and optical inputs, and if so, was the sound the same?

Hello Walter,
I will answer your question. However, since I was a pure design engineer, I am not good at evaluation like an audiophile.

1. There is no loudness setting on D03. Adjust using the tone control.

2. The included power adapter is 32V, but the power supply voltage can be 36V. 50V / 3300uF is used for the power supply capacitor of the PC board.
However, even at 32V, the case gets quite hot in the summer. If it is 36V, it will overheat further. In Japan, where I live, use at 36V is difficult in the summer.

3. I connected E30 and D10s to A04 / A07 and listened to them, but as far as I can hear, there is no clear impression that D03 is inferior in sound quality.

4. Yes, I compared the sound quality with a USB / OPT / COAX connection. If you measure it with a measuring instrument, there will probably be a difference, but as far as you can hear it directly, you will not feel a clear difference. However, RCA analog inputs are significantly inferior to digital.

If you are interested in D03, please try it once. Maybe the actual sound quality is better than you can imagine. I thought so myself.

 

[Walter]

Hello Walter,
I will answer your question. However, since I was a pure design engineer, I am not good at evaluation like an audiophile.

1. There is no loudness setting on D03. Adjust using the tone control.

2. The included power adapter is 32V, but the power supply voltage can be 36V. 50V / 3300uF is used for the power supply capacitor of the PC board.
However, even at 32V, the case gets quite hot in the summer. If it is 36V, it will overheat further. In Japan, where I live, use at 36V is difficult in the summer.

3. I connected E30 and D10s to A04 / A07 and listened to them, but as far as I can hear, there is no clear impression that D03 is inferior in sound quality.

4. Yes, I compared the sound quality with a USB / OPT / COAX connection. If you measure it with a measuring instrument, there will probably be a difference, but as far as you can hear it directly, you will not feel a clear difference. However, RCA analog inputs are significantly inferior to digital.

If you are interested in D03, please try it once. Maybe the actual sound quality is better than you can imagine. I thought so myself.

Thank you very much. I was worried about the heat issue, as I live in Cambodia, although I do use air conditioning probably 45 weeks a year. Have you ever checked to see if the heatsink can be safely removed without damaging the chip? I'm just wondering if the stock thermal compound is adequate. My computer is my only source for both audio and video, so the quality of the analog inputs is unimportant to me.

I know you have said you prefer the sound of the AO200 to the DA-9. How do you think the DA-9 compares to the D03? (The AO200 is not available here or in Thailand, so far.)

 

[Toku]

I live in the middle of Japan, in the NGOYA area, which is famous for being very hot in the summer. It can reach 38-39 ° C during the hottest months. Is this temperature about the same as Cambodia?

I purchased the DA-9 shortly after its release, but found a symptom that the DC offset voltage of the amplifier output was constantly fluctuating. As a result, there was a problem that pop noise was generated when the power was turned on / off or when the input was switched. I reported the symptoms to SMSL and eventually returned the DA-9. I haven't received any news that this issue has improved since then. SMSL always ignores such issues.

However, I have a very good impression of the sound quality of the DA-9. I would even like to buy it again if the problem is resolved.
It is difficult to compare AIYIMA DO3 and DA-9. The D03 uses a built-in inexpensive DAC, and the DA-9 connects an external DAC. I connected the Topping E30 and SMSL M500 to the DA-9 and I feel the difference. I'm not good at explaining sound quality in detail, but the DA-9 still has a slight advantage. However, although the D03 is a built-in inexpensive DAC, the sound is excellent enough and the difference is not big. The final decision depends on the individual's preference for sound quality.

If the cost of DA-9 + DAC is possible, we recommend it. However, collect information on the subsequent operation status of DA-9.

 

[Walter]

I live in the middle of Japan, in the NGOYA area, which is famous for being very hot in the summer. It can reach 38-39 ° C during the hottest months. Is this temperature about the same as Cambodia?

I purchased the DA-9 shortly after its release, but found a symptom that the DC offset voltage of the amplifier output was constantly fluctuating. As a result, there was a problem that pop noise was generated when the power was turned on / off or when the input was switched. I reported the symptoms to SMSL and eventually returned the DA-9. I haven't received any news that this issue has improved since then. SMSL always ignores such issues.

However, I have a very good impression of the sound quality of the DA-9. I would even like to buy it again if the problem is resolved.
It is difficult to compare AIYIMA DO3 and DA-9. The D03 uses a built-in inexpensive DAC, and the DA-9 connects an external DAC. I connected the Topping E30 and SMSL M500 to the DA-9 and I feel the difference. I'm not good at explaining sound quality in detail, but the DA-9 still has a slight advantage. However, although the D03 is a built-in inexpensive DAC, the sound is excellent enough and the difference is not big. The final decision depends on the individual's preference for sound quality.

If the cost of DA-9 + DAC is possible, we recommend it. However, collect information on the subsequent operation status of DA-9.

Thank you. I will do that. I am a few months away from actually making a purchase--hopefully only two or three but it depends upon governmental travel decisions that I have no control over, as well as seeing if a likely upcoming change from working at home to opening an office also makes a significant change in the usage of this system or its budget. At the moment, since I can only research and plan, and since even when I am ready to make a decision I will have no opportunity to audition components at home, I'm trying to determine the best options at various price points from $500 to $2,000+. Doing the research and making plans is how I relax when I take a break from doing research and making plans for work!

 

[Bushellj]

I live in the middle of Japan, in the NGOYA area, which is famous for being very hot in the summer. It can reach 38-39 ° C during the hottest months. Is this temperature about the same as Cambodia?

I purchased the DA-9 shortly after its release, but found a symptom that the DC offset voltage of the amplifier output was constantly fluctuating. As a result, there was a problem that pop noise was generated when the power was turned on / off or when the input was switched. I reported the symptoms to SMSL and eventually returned the DA-9. I haven't received any news that this issue has improved since then. SMSL always ignores such issues.

However, I have a very good impression of the sound quality of the DA-9. I would even like to buy it again if the problem is resolved.
It is difficult to compare AIYIMA DO3 and DA-9. The D03 uses a built-in inexpensive DAC, and the DA-9 connects an external DAC. I connected the Topping E30 and SMSL M500 to the DA-9 and I feel the difference. I'm not good at explaining sound quality in detail, but the DA-9 still has a slight advantage. However, although the D03 is a built-in inexpensive DAC, the sound is excellent enough and the difference is not big. The final decision depends on the individual's preference for sound quality.

If the cost of DA-9 + DAC is possible, we recommend it. However, collect information on the subsequent operation status of DA-9.

Hi Toku

The Aiyima D03 seems to be a bit of a special beast as it is based on a completely different Texas Instruments Chipset from the other TPA325x based amplifiers and of course many of the newer SMSL amplifiers are now based on the Infineon Merus MA12070. Both these latter chips have an analogue input as far as I am aware and therefore should be optimised for Sound Quality with an Analogue signal. (I am aware that Infineon provide different versions of their chips with different inputs but the analogue input seems to be the most common in current use).

The Aiyima D03 is different in that the inputs are digital so are optimised for digital signal sources. The RCA Analogue inputs on this Amplifer are a bit of an afterthought and use a low end ADC on the front end which will have a negative affect on the RCA input performance of this amplifier. Using a quality ADC on the front end would probably double the price of the amplifier !

Adding a better DAC before the D03 (using the RCA inputs) seems to be a very strange way to test this amplifier as it just wasn’t designed to be used this way and I think provides a very unfair comparison with the other amplifiers based on an analogue signal flow.

I think you should only consider purchasing the Aiyima D03 if your primary use is going to be using the Digital Inputs. The RCA input is a nice to have but using this input to compare with other amplifiers does seem a bit unfair. That said, the reviews that have revealed this issue are most valuable when making purchasing decisions. I will add my impressions once I have received my Aiyima D03 and compared with the A04 and A07 Amplifiers I am currently using.

 

[Rubbersoul2]

Currently, I am using a D03 with a 4Ω speaker connected. From time to time, I am conducting a loud playback test while preparing for complaints from the neighborhood. The D03 can easily drive low impedance speakers and has excellent damping capability. This point has the same or better ability as A07.

thankyou you make a lotta sense /prepairing for neighbours is a majour fact for apartment dwellers ,even with concrete soft furnishings n folk music . DO3 is firmley winning my favour eye to buy apreciate your well investigated research detail all helps .

 

[Schlippwhip68]

thankyou you make a lotta sense /prepairing for neighbours is a majour fact for apartment dwellers ,even with concrete soft furnishings n folk music . DO3 is firmley winning my favour eye to buy apreciate your well investigated research detail all helps .

Mine arrived on Saturday. took 2 weeks from China to UK. Not disappointed at all. Even the lesser RCA is decent enough, I would say it sounds a little drier than the digital inputs but not a disaster by any means. The case does get warm and it left me wondering why the lid is not vented like an integrated A/B. I am tempted to drill the lid of the casing like a medieval headache cure.. Currently driving a pair of Mission 751 speakers (28 years old) and it sounds excellent using iTunes @ 24/96hz on Windows 10 via an HP 800 G2 micro PC...I also own the A04 and running the easy listening opa2604 with it and the D03 was instantly better in my ears...any questions feel free to ask.