Topping D90

General Information

Topping D90
Topping D90 is a new balanced flagship DAC by Topping, built around the latest Asahi Kasei Microdevices flagship DAC / AMP chip, AKM AK4499EQ. It is also equipped with the second generation XMOS XU208 USB interface chip, the AKM AK4118 S/PDIF receiver chip and the CPLD programmable logic chip. It uses German Thesycon controllers. It is equipped with a pair of AccuSilicon 451584 MHz and 491520 MHz femtosecond clocks, ensuring the best sound quality.

Flagship DAC offering a velvety sound output power

Topping D90 is equipped with the flagship Asahi Kasei Microdevices AKM AK4499 digital/analog converter chip, boasting AKM’s Velvet Sound Technology, which makes it a very efficient DAC, providing exceptional sound quality and rich details. AK4499EQ current-output DAC is a successor of the AK4497EQ and is produced using the same Premium Audio LSI process and Non-Magnetic Packaging technology originally developed for the AK4497EQ. These techniques dramatically improve noise performance, especially in the traditionally problematic lower frequency range. It achieves industry-leading low distortion and low noise characteristics through newly developed distortion reduction technology and low noise design. The AK4499EQ supports PCM and DSD512 inputs up to 768kHz. AKM’s Low-Distortion Technology has been optimized for the AK4499’s current-output architecture, resulting in a THD+N measurement of -124dB. The AK4499EQ achieves SNR of 140dB in mono mode. It has been implemented with 4 OPA 1612 amplifiers, 7 hi-fi capacitors, CPLD processing using 2 Accusilicon femtosecond clocks that provide completely noise-free and jitter-free sound. This transducer provides soft, smooth and vibrant sound quality, that’s why it’s called Velvet Sound Verita. The sound output is natural and soft, which accurately reproduces all the micro details in your music.

USB interface is controlled by the second generation XMOS XU208 USB interface, well known to audiophiles and offering an exceptionally transparent sound. XU208 chip is a representative of the xCORE-200 Series by XMOS and is a 32-bit mulitcore microcontroller characterized by its low latency and timing determinism. Unlike conventional microcontrollers, XU208 is cabable of exectuing multiple real-time tasks simultaneously and communicate between tasks using a high speed network.

A myriad of inputs

The Topping D90 is equipped with a high-quality USB XMOS XU208 chip, which offers a high PCM sampling rate up to 32-bit / 768 kHz and native DSD up to DSD512, and a crystal clear background without noise. This set is simply unique and charming. IIS input is supported via HDMI port, which provides a better signal, which is sent to the DAC for decoding services, this function only uses IIS signal via HDMI, so you cannot use HDMI via PC, TV or set-top box. The sound quality is natural, smooth and charming, start listening to all your music with very good precision. The D90 is also equipped with AKM AK4118 chip, which covers all S/PDIF connections, which is able to decode PCM up to 24-bit / 192 kHz, completely free of noise and interference. It takes input signals via optical, coaxial and AES input ports.

D90 offers following inputs: USB-B (XMOS), optical, coaxial, AES, IIS and Bluetooth 5.0. USB and IIS inputs support up to PCM32bit / 768 kHz and DSD512 Native. Optical, coaxial and AES inputs support up to PCM24bit / 192 kHz.

Bluetooth 5.0 support with Qualcomm flagship chip
Topping D90 is equipped with the flagship Bluetooth Qualcomm chip, CSR 8675, offering a strong and stable Bluetooth connection that is delay-free and supports all codecs such as aptX, aptX HD, aptX LL, AAC, LDAC and much more. Offers high-resolution 24-bit / 96kHz LDAC over a wireless connection. Supporting LDAC and aptX HD, the Topping D90 delivers crystal-clear audio without delays.

Wide dynamic range and excellent signal-to-noise ratio
Topping D90 provides a wide dynamic range of 127dB and an amazing signal-to-noise ratio – 127dB, which provides greater extensions at the lower and higher ends and amazing crystal-clear background, without any signs of noise.

Dual output ports

Topping D90 is equipped with dual output sockets, XLR outputs offer 4Vrms output power at 0dBps, and the other output port, an unbalanced RCA offers 2Vrms output power at 0dBps. It provides enough power to power any of your demanding devices, whether it’s headphones or a speaker system. The D90 can send a signal through both output ports at the same time, so you can use multiple tools at the same time. It is equipped with a volume control function, so it can be used both as a digital-to-analog converter and as a preamplifier converter. The volume control can be turned off so that the D90 works only as a digital-to-analog converter.

Remote included

D90 is equipped with a remote control that can be used for various functions such as on / off, mute, volume control, input type change, DAC filter type change or OLED display brightness adjustment.

  • Product type: DAC
  • DAC Chip: AKM AK4499
  • USB Interface: XMOS XU208
  • SPDIF Interface: AK4418
  • BluetoothL 5.0 / Apt-X HD / LDAC
  • Inputs:
    • 1x I2S LVDS (HDMI)
    • 1x Optical Toslink
    • 1x USB-B (XMOS)
    • 1x Coaxial S/PDIF
    • 1x AES/EBU
  • Supported sampling rates:
    • USB : PCM up to 32bit 768kHz / Native DSD up to DSD512 / DSD DoP up to DSD256
    • I2S : PCM up to 32bit 768kHz / DSD up to DSD512
    • Coaxial, Optical, AES : PCM up to 24bit 192kHz
  • Outputs:
    • 1x Balanced XLR
    • 1x Single-Ended RCA
  • Output voltage:
    • RCA : 2Vrms @ 0dBFS
    • XLR : 4Vrms @ 0dBFS
  • Dynamic range (A-Weighting): 128dB
  • Power Supply: AC110V/AC220V 50Hz/60Hz (switchable) via IEC (cable included)
  • Case material: Aluminum
  • Dimensions: 22 x 16 x 4.5 cm
  • Color: Black or SIlver
  • Package:
    • 1x Topping D90
    • 1x IR Remote Control
    • 1x Bluetooth antenna
    • 1x USB Cable
    • 1x Power cable
    • 1x User manual
    • 1x Warranty card

Latest reviews

Pros: Smooth, non-fatiguing sound. Pre-amp option. I2S input. Remote control. RCA and XLR outputs can be separately disabled.
Cons: Bit flat-sounding. Pre-amp output setting lowers sound quality.

Thanks to Shenzen Audio for sending me the Topping D90 for review.

After I reviewed Schiit Audio's Bifrost, I had quite a few people interested in my reviewing the equally priced Topping D90. Topping has been known for its DACs that measure very well, which appeals strongly to a subset of people who want some form of verified performance measure.

While I'm personally not interested in DACs that use the AKM4491 or 4493, my recent good experience with FiiO's M11 Pro and it's AKM4497 DAC made me more interested in the AKM4499-based Topping D90.

I tend to be somewhat wary of well-measuring DACs. Another well-measuring DAC, the Benchmark DAC 1, was a popular DAC over a decade ago when I started on Head-Fi, yet it wasn't exactly the most musical — it tended to sound rather bright, and "digital". Likewise, some of FiiO's DAPs, while measuring well, up to at least the M11, sound a bit sterile.

The DACs that buck this trend have been from Chord, with their FPGA+transistor designs, though somewhat dependant on how they are set-up with a suitable transport.

So, it was with interest that I agreed to review the Topping D90. Functionality-wise, it's about the size of the Schiit Bifrost, and slightly slimmer. Whereas the Bifrost focusses on upgradability and is PCM-only, the Topping attempts to be a jack of all trades, supporting up to 768k input (via USB) as well as DSD. It also supports a pre-amp output (bypass-able for a possible increase in sound quality).

XLR and RCA outputs can be switched on and off separately for a choice of where music goes, the pre-amp can be bypassed, and the digital filters on the AKM4499 can be changed as well.


I ran the D90 initially straight from my Mac Mini Roon server via USB. With both connected to an Audio-gd Master 9 or ALO Audio Studio Six, I could readily A/B them. I subsequently tried both from a Soundaware D300REF streamer, the D90 connected via I2S (and AES briefly) and the Bifrost via S/PDIF.

I2S, for the unfamiliar, is a connection between internal DAC components. While S/PDIF, AES and Toslink carry both digital data and the clock signal in one connection, internally, a DAC separates out the components, transmitting them over separate lines, in much the same way you have composite and component video, with their one and three connections respectively.

Taking the I2S connection outside the DAC, there is a potential for improved sound quality, though whether it makes for an improvement over AES and S/PDIF is likely DAC-dependent. There are also a number of different connection arrangements, so you have to ensure that your digital transport's I2S is compatible with the With the Topping D90's I2S. To that end, the D90 has a special mode, accessed by holding the front power button down while switching it on at the back. This allows a compatible I2S mode to be selected.


Initial impressions reminded me of the FiiO M11 Pro, which uses the AKM4497. The D90 has a smoothness to the sound which makes for pleasant listening, though, regardless of filter choice, was a bit flat-sounding, and with pre-amp mode on, didn't bring out quite the level of nuance and detail that the Bifrost 2 can. The Bifrost 2 brought out a bit more depth and feeling, such how it reproduced instruments on David Chesky's Jazz in the New Harmonic. The subtleties of both the decay of notes and their echo off the recording venue were more noticeable from the Bifrost.

Turning off pre-amp mode brought things closer to the Bifrost, if not quite up to Yggdrasil level. With more apparent detail and less of the "flatness", the D90 seemed to do its best not to impose itself on the music.

Switching to the D300REF as a source seemed to overcome the D90's limitations, bringing it (in a very expensive manner) up to near Yggdrasil level. Listening through an Audio-gd Master 9 with Van Den Hul The Orchid cables to a pair of Final D8000 Pro, the Yggdrasil still just had an edge on depth and nuance when listening to Jazz in the New Harmonic by David Chesky (192/24) or Mark Ribot y los Cubanos Postizos (16/44.1 TIDAL) with the D90 set to filter 1 (linear phase).

Slightly confusing the issue was a small mid-bass hump in the Yggdrasil, a result of uneven crosstalk caused by the DC offset circuit in the output stage that can make the DAC sound like it has a bit more bass on some tracks.

Compared to my other, usual go-to DAC, the Chord Hugo 2, the Topping/Master 9 or THX AAA 789 combo couldn't compete to the direct headphone output in terms of nuance and detail, though only on the best-quality recordings I have here, such as Decca masters and recent Chesky recordings.


Since I wanted to experiment with up-sampling to the D90, I switched to using a Kitsune tuned Singxer SU-1 USB to S/PIDF and I2S converter. Some quick experimentation with HQPlayer to see what, if anything could be achieved by PCM up-sampling, I had some pleasant results from the SINC filters, which produced a very "floaty" sound and the million-tap closed-form-M which emulates something similar to the punchy and precise filter that Schiit Audio uses. The latter I reckon was about spot-on for most music, balancing up the overt smoothness of the DAC beautifully and making for very pleasant listening.

What was most surprising about the comparison, however, was how close it was possible to make the D90 come to the Yggdrasil for about two-thirds of the cost (or more if you include a HQPlayer licence). For most music I don't believe I would be able to make out the difference in a level-matched comparison.


That left my impression of the Topping D90 of a DAC capable of being quite detailed and smooth in the right system, such as one with a good USB, IIS or coax/AES transport. In others, and especially with the pre-amp circuit engaged, it can end up sound a bit flat and un-involving. All the same, one can't ignore the great value it provides for the $700 asking price.

Impressions from viewers of my video confirmed this, with some reporting (mainly the new MQA version) a positive experience, and others feeling it sounded too flat.

As with all DACs, system synergy has to be considered, but I can still recommend the D90 as a standalone DAC, especially for people who wish to go the extra mile to get it sounding good in their system.
Your reviews are always appreciated, @Currawong

And I like your analogy, because all measurements are done in the frequency space - nothing in the time domain.
@Currawong Have you tried out DSD upsampling with the D90 yet, DSD direct mode is supposedly active when set to DAC MODE, bypassing the built-in ∆Σ modulator which supposedly should increase SQ even further.
Pros: Optical input works
Cons: Catastrophically broken USB implementation
Cannot turn off display
The Topping D90 was the first commercial DAC using AKM's latest and greatest DAC chip, the AK4499. On paper, this DAC chip boasts a THD+N of -124dB, which is lower and better than AKM's previous flagship, the AK4497 at -116dB. Many people believe that DAC technology has been more or less figured out at this point, and that a $100-200 DAC is good enough for most purposes. Therefore, at $700, the Topping D90 is held to a higher standard and must perform flawlessly for it to be a good buy.

Upon release, certain sites measured the D90 and gave it the highest praise. This is exactly why I bought the Topping D90. I thought it would be the last DAC I would ever need to buy. Unfortunately, the Topping D90 stumbled right out of the gate for me.

The first input I tried was USB. Immediately, there were two issues:

  • USB noise interference
  • Popping sound a few seconds after audio playback stops
There was a faint, but very audible noise coming from my headphones when no music was playing. To make sure it was the D90 and not my amp or cables, I plugged in several other USB DACs into my amp, as well as trying multiple cables. (None of the cables cost more than $15.) No other DACs exhibited the noise. In addition, after a few seconds of no playback, I heard an audible pop. Apparently, in Windows 7, the driver goes to sleep after a few seconds. This is documented at:

This is ridiculous. I have plenty of older DACs that don't exhibit this behavior. It doesn't matter if you set Windows settings to always never have the USB device or port sleep. The driver is ordering the DAC to go to sleep, thus the popping.

Fortunately, my PC tower has optical out. The D90's optical input works perfectly, though you're limited to up to 24-bit/192khz instead of up to 32-bit/768khz. I was happy with using optical input exclusively.

For this review, which came 3 months after purchase, I wanted to see if the issues mentioned above were due to Windows 7's USB audio implementation. So I obtained a Windows 10 test laptop. The issues became worse when I plugged the D90 into the laptop. The audio I heard crackled heavily for 1 minute. And then suddenly, the laptop no longer recognized the D90. I tried plugging it back into my PC tower. Nothing. The D90's USB input had completely died. Fortunately, optical input still worked. Did the USB input break because I had the optical cable plugged in with a music signal at the same time? Who knows, but it still shouldn't have broken like that.

One additional point of contention is that the display can't be turned off while the unit is operating. You can change how bright it is, but you can't turn it off completely. This is a major distraction when watching movies in a darkened room. You'll need to cover up the display with some electrical tape. Easy fix, but on a $700 unit, this shouldn't even be an issue.


With the D90's USB input giving me issues from the very beginning, then suddenly failing on me when writing this review, I can say with certainty that you are playing a slot machine when buying this device. It does have a 1-year warranty, but the exorbitant shipping cost for warranty service from North America to China has discouraged me from sending it in. At least I can still use the unit's optical input, and it does work well enough there, so I'll give it an extra half star for that.

Not recommended at all.
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Blech, thanks for the heads up, I now have zero interest in this persnickety, overpriced hodge-podge. 😅
I've used the D90 MQA for a month now with Windows 10 and have not encountered any of these USB issues, any background noise, or any popping sounds. Did you test with a different USB cable? Have you considered exchanging the unit in case yours is faulty? Have you downloaded the latest drivers and firmware from Topping's website?
Hi headwig,

Please read the link in the review for more details as to how I tried unsuccessfully to correct the USB issues. I tried everything you suggested. I am not exchanging the unit, as mail processing is still significantly delayed during COVID-19, and express shipping the unit to China would cost over $100.

Correction: I stated in an earlier reply that the iFi MiDSD BL had special drivers that disabled sleep mode. This is incorrect; I downloaded special firmware that disabled sleep mode. To my knowledge, the D90 non-MQA does not have new firmware.
Pros: Neutral, Plenty of inputs, Value for money
Firstly I would like to thank Topping for sending me this sample to review.

*disclaimer: This sample was provided for the purpose of writing a review, no incentive was given to write a favourable review. All opinions expressed are my own subjective findings

Gear Used:
TV > D90 (optical) > Rotel RB-06 > B&W 606
PC > D90 USB > Keces S3 > HE-500 / HE6SE
Pixel 3a (LDAC) > D90 > Rotel RB-06 > B&W 606


Tech Specs:

Packaging, Build Quality and Accessories:
The D90 comes in the new style of Topping packaging, a sleek matte black box with only Topping written on the top. It feels quite premium and is very strong, lift off the top of the box and the D90 is held tightly in place by a foam insert, there are separate slots for the accessories. I really like the new packaging, it makes the products feel a little more premium.

Again like the DX7 Pro, the D90 is much sleeker than earlier Topping products, the case is perfectly machined and shaped, and it feels very solid. The inputs on the back are all of excellent quality and the front display is clear and easy to read. There is a power button on the front along with selection buttons that also act as volume up/down in pre-amp mode. Topping are really working hard to make good looking, great sounding bits of kit.

Accessory wise you get a remote control, Bluetooth antenna, power cable and USB cable. To be fair there isn’t anything else needed so that’s good.

The D90 is a DAC and it can also be used as a pre-amp, you can change between fixed and variable output easily. It has USB / I2S / Coaxial / Optical / AES and Bluetooh inputs. The last one is something that Topping are putting in to a few of their models and they are using the latest codecs for the best fidelity playback whilst wireless.

The DAC has digital filters (AK4499) which is fairly common, sound differences are subtle but you can fine tune it to your liking. There are single ended and balanced outputs.


For the most part I left the D90 in mode 3, I did try the other filters and as previously put they make a small difference. I have also mainly been using the D90 in my hifi system as it fits perfectly into the system. However you use the D90, it will allow you to forget about getting the best out of your source and let you focus on components downstream. The D90 has got to be one of the most linear and detailed DACs that I have listened to. It is incredibly faithful to the recording, completely getting out of the way of the music, which is what I want a DAC to do. It does not flatter you with false warmth, it purely presents the music in a neutral manner.

There is width and depth to the soundstage, there is hard hitting bass, defined midrange and sparkling highs, whichever input you use. Bluetooth is of course the least faithful, however don’t let that make you not use it. The D90 manages to lose very little when used in Bluetooth mode, and it is by far the best implementation I have heard.

We are definitely at that point with DACs where the D90 provides, in my opinion, all the fidelity you could possibly want out of a digital source. Distortion levels are way beyond the capability of our hearing, the frequency response is as flat as you can get, all wrapped up in a neat package. As far as standalone DACs go, if you don’t need network streaming capabilities, the D90 should suit most peoples needs. The sound is never forced, it is grain free and crystal clear. There is also never any glare up top, Toppings implementation of this particular AKM4499 chip is superb as it is analytical but not clinical or cold.

Suffice to say the D90 is an excellent, true to source DAC. It will fit neatly into any system, the pre-amp mode works excellently in any hifi setup with a power amp, yet the pure DAC mode can be hooked up to any headphone amp or integrated amp without issue. The digital filters allow you to tune the sound to a small degree. Pair this DAC with the new A90 amp and you will have a reference point but also an enjoyable system that will power 99% of headphones on the market today.


The price point for the D90 is exceptionally good if you take into consideration how well it performs. It doesn’t have tons of bells and whistles but it does have a superb bluetooth implementation which many don’t. Sound wise the D90 delivers a true to source sound that is detailed, open and neutral, but without a cold or clinical tonality. If you want a DAC that you can forget about, the D90 is excellent, it lets you focus on the components further downstream.

Sound Perfection Rating: 10/10 (I cannot fault it, in general or for the price)


This is an exceptional bit of kit. I made an evaluation that just as the tech for mobile phones and pcs has improved over the last eight years since the conception of my old DAC so it would be in digital hifi. The most up to date chips and a really dedicated engineering team underpin this design. This surpasses my originally £1300 DAC and I have read reviews that compare it favourably up to $3000. I feed my mainly wav and flac collection from Teddy Pardo Lps powered nuc based jriver win10 pro (with Audiophile Optimizer) via usb straight to the DAC. I was immediately struck by how much more detail and clarity was revealed. I use the internal pre amp to feed twin Schiit Vidar and Kef R3 bookshelf. I have never played my digital music through an additional pre amp therefore cannot tell you if you have a three grand pre in addition to the D90 would raise the bar further.

I'm using my old DAC to feed my smsl sp200 headphone amp mogami XLR in. I'm not a fan of cable swapping and am pretty much in near field listening a deal of the time with the Kefs. Right next to the main system is my headphone amp hence no ins and outs cable wise. Do swat up on the Topping A headphone amp that is the latest addition to the stable. 1 - HPAEC1840 Additional Pair of Velour Ear Pads is gaining rave reviews. The MQA version of this DAC is said to be even better. I had the choice but that format is not something I need, much like my DSD requirements.