[sajunky]

My ears are sensitive to very high frequencies, and for me various DACs really only differ in the highs. As a physicist, this makes sense, reconstructing low frequencies from a much higher frequency digital signal should be much easier than massaging the highs around Nyquist. When people talk about the "tight bass" or "upfront mids" and such for a DAC, I can't help but think that it has more to do with other pieces in their chain...or how those pieces work together with the DAC, which is non-linear, but we know that "pairing" is important and so by default we know that we live in a non-linear space with audio components.

Anyways, I've been playing with the various filters on the D90, and at least for me they make a big difference. It isn't subtle at all. But then again, I will recoil in severe ear pain at high pitched squeals that are inaudible to others (this isn't necessarily a good thing, since most people don't take care to regulate the volume those pitches).

Your ears are very good, but others should also notice a harshness in high frequency tones,. It is a typical weakness in this type of converters. High pitched squeals don't come and go, it is a constant unnatural presentation of high tones. It must be something else you hear, perhaps Topping supplied you a unit with fake opamps. Few years ago it happened to me with D30.

Don't stop researching on D90, I am sure you need to compare ringing bell filter with a nature - or - at least a good NOS R2R DAC. A gong will not be limited to the main tuned frequency and immediately recessed when ringing is transitioning to a different tone. It will ring and ring again, despite of the foreground music you will stilll be able to hear it. No digital filter can restore what is already lost in the decimation & noise shifting processing. The same with piano notes, guitar plunks and a total harmonic coherency of different instruments across the entire spectrum. In other words comparison gear is needed like Denafrips Ares or Audio GD R2R-11. I only mention a cheapest ones, but it is where enjoyement begins.

 

[]eep]

I have been using a Topping D90 (MQA version) for about a week now, and I still need more time before I can make a final decision about this DAC and its value. It certainly ticks many boxes in terms of functionality/features. But I have to hear it through many different familiar sources before I can really judge it appropriately.

So far I'm quite impressed by the implementation of the AKM flagship chip at this price point (hopefully they get the factory going again soon). Topping seems to have kept costs as low as possible while still delivering a solid piece of electronics (time will ultimately tell just how robust it is). There are trade-offs, but so far it looks as if those trade-offs are reasonable. Tear-downs of the D90 show solid components in the places where they need to be.

My ears are sensitive to very high frequencies, and for me various DACs really only differ in the highs. As a physicist, this makes sense, reconstructing low frequencies from a much higher frequency digital signal should be much easier than massaging the highs around Nyquist. When people talk about the "tight bass" or "upfront mids" and such for a DAC, I can't help but think that it has more to do with other pieces in their chain...or how those pieces work together with the DAC, which is non-linear, but we know that "pairing" is important and so by default we know that we live in a non-linear space with audio components.

Anyways, I've been playing with the various filters on the D90, and at least for me they make a big difference. It isn't subtle at all. But then again, I will recoil in severe ear pain at high pitched squeals that are inaudible to others (this isn't necessarily a good thing, since most people don't take care to regulate the volume those pitches).

So I was listening to a Tidal stream that started with Pat Metheny's latest album (very nice!) but ran off on a stream of consciousness to a bunch of other random tracks, and I had filter 1 selected on the D90 (it is the sharpest and most analytical around 20kHz). There was a tune that had a super high frequency resonance bell ring, and it really got to my ears. This doesn't often happen with other DACs, and I was impressed, as well as disturbed, this was one of the first times I've had that happen through a virtual audio source. Is it the Tidal track? The MQA compression/folding (I'm skeptical of this format, but it could have some weird artifacts)? I don't know. I'll have to keep listening and comparing. But I hope that Topping can come up with some more filters, via a firmware update, giving us more options. Or is it limited by the chip? I don't know.

Anyways, one day I'll write a full review, but for now I'm just enjoying the exploration of this new generation of DACs, in the past couple years it seems like things have really gone up a notch, but at the same time there is still no universal solution to deal with the highs and the roll-off. This seems to be where the game is at, now.

I think it's an interesting and honest observation. It makes me think, and I'm still thinking if and how your hearing is different. I can't speak for you since my hearing over 15k has been lost with age but I am very critical about high frequencies. Not that it is too much (usually too slow or rolled off) but simply not 'right'. There is some artificiality about it. What I have found out over time (double entendre) that it has to do with rise and decay of notes. Timing errors, phase, pre- and post-echos. Not with amplitude.

The problem is that conversion can be done in two ways and to confuse the issue further; a dac is not only the transition between digital and analog but part digital and part analog and the method you chose has consequences for the analog part as well (with current technology).
If you choose multibit, or R2R or ladder you might think you have to 'massage around Nyquist' (you don't actually *) but you can keep the analog part very, very simple (*) so that it doesn't get in the way of the music (ie no information loss).
If you choose single bit sigma delta you are picking up the sum of the fractures, glue them together and then you have to get rid of all the excess glue so to speak (that's the high frequency noise and smearing). DS chips are easier to fabricate due to looser tolerances but because of the high amount of oversampling you get a lot of HF hash and phase smearing. That impacts transients and that is what makes the unnatural sparkle in the high frequencies. You need a lot more filtering and you need a complex I/V and analog amplification stage that does get in the way of the music (information is lost).

If you convert over a ladder of resistors you need to calibrate them well but without oversampling (NOS) there is no unnatural pre-echo or pre-ringing. There will be some post-ringing but that is common in nature (except of course in Star Trek where they have 'inertia dampers'). There has been a lot of improvement in delta sigma dacs, especially in reducing this effect but I don't agree that even more filters will fix that. Actually, less is more and I'm back to where I arrived 10 years ago. (*) Better than new DS dacs (unless you play DSD where I'm not sure what sounds better).

As to physics and Nyquist, that's all very nice. In my experience that is very instrumental in developing a professional tunnelvision. It's always the same kind of people namedropping 'Nyquist this', 'but Nyquist', 'you don't understand Nyquist'. He might have been an engineer and physicist but his theory is more what we call information sciences. It's all virtual, not physical. And that's quite descriptive of the chasm between believers in scientism and people who believe their ears (just fill in the title of your favorite eternal flamewar and you see the two camps emerge). In the words of Chris de Burgh:
"And a chance to work it out,
For we cannot live together, and we cannot live apart;
It's the classical dilemma between the head and the heart;"

* after playing with a nice ES9038Q2M DS Dac that has all the modern features for convenience and a NOS, filterles R2R with only 1 resistor for the output stage I wanted to upgrade. I was looking at 2 choices: SMSL M400 (about the same as the A90) and the Denafrips Ares II. After lots of searching for reviews, opinions and comparison, with my experience in modifying and comparing dozens of dacs, I came to believe that the Ares was the better choice. And I'm quite certain that it is. Only when I compare the Ares to another good DS and my oldest dac, an R2R/multibit with 4 parallel vintage Philips chips that I bought for €45 10 years ago and I modified to the simplest form of output that is not according to spec, the outcome was very surprising. The oldest and cheapest and most limited dac (24-96 max) that I know measures like s#it won hands down. It has better space, clearer defined, highs are clean but detailed, it doesn't clip or saturate with soprano or piano high notes. And the bass is fast and clean too. It's not just the highs that are in order. And 'Nyquist' might say that I will get sidetones or spuriae but I haven't heard him play the hobo yet (used to tune a symphony orchestra).

 

[Deolum]

What exactly are the differences between D90 and D90 MQA besides MQA?

 

[sajunky]

What exactly are the differences between D90 and D90 MQA besides MQA?

Very little. Some low cost improvement in a hardware, insignificant, IHMO. Most of a balance goes for covering MQA licencing fees, a bigger markup too.

 

[Deolum]

Very little. Some low cost improvement in a hardware, insignificant, IHMO. Most of a balance goes for covering MQA licencing fees, a bigger markup too.

But what exactly?

https://soundnews.net/sources/dacs/topping-d90-mqa-review-majestic-quick-accurate/

This guy wrote a whole review about the D90 MQA after he wrote one about the D90.

 

[Marlowe]

AFAIK the only differences between the standard D90 and the MQA version is the MQA decoder itself and an upgraded USB chip (XMOS XU216 in the MQA version; the standard version uses XMOS XU208). They are otherwise identical.

 

[Deolum]

AFAIK the only differences between the standard D90 and the MQA version is the MQA decoder itself and an upgraded USB chip (XMOS XU216 in the MQA version; the standard version uses XMOS XU208). They are otherwise identical.

Thanks. Well thats worth to write a whole new review about.

 

[Deolum]

Anyone else likes filter 6 the most?

 

[JHern]

Your ears are very good, but others should also notice a harshness in high frequency tones,. It is a typical weakness in this type of converters. High pitched squeals don't come and go, it is a constant unnatural presentation of high tones. It must be something else you hear, perhaps Topping supplied you a unit with fake opamps. Few years ago it happened to me with D30.

Don't stop researching on D90, I am sure you need to compare ringing bell filter with a nature - or - at least a good NOS R2R DAC. A gong will not be limited to the main tuned frequency and immediately recessed when ringing is transitioning to a different tone. It will ring and ring again, despite of the foreground music you will stilll be able to hear it. No digital filter can restore what is already lost in the decimation & noise shifting processing. The same with piano notes, guitar plunks and a total harmonic coherency of different instruments across the entire spectrum. In other words comparison gear is needed like Denafrips Ares or Audio GD R2R-11. I only mention a cheapest ones, but it is where enjoyement begins.

I have been listening a lot again today, and it is like the sound tends to agitate the tinnitus in my right ear (it is usually tolerable).

I have a Sony PCM-D100 portable recorder that I can use to test this further. I was just reading an article about using it to record ultrasonic bat squeaks (I am thinking about trying to record some myself). In any case, using similar methods and the ultrasonic reach of the recorder, I should be able to turn up some solid empirical data to tell me what is coming out.

I wonder about the kinds of things that slip through at the ultra-high/ultrasonic border region in the recording, mixing, and mastering process. If the engineer's ears are not highly attuned to these, then a lot of junk could make it through in that narrow frequency band. And the problem with making more transparent DACs is that those of us who are sensitive are affected by it...even if it isn't easy to pinpoint as an articulated coherent sound.

In any case, I think this is something that Topping might be able to fix with a firmware update and addition of more aggressive filter(s) for those of us who are sensitive...so long as the hardware permits it (I don't see why not, but you never know). If so, that would be good for all concerned.

 

[JHern]

I think it's an interesting and honest observation. It makes me think, and I'm still thinking if and how your hearing is different. I can't speak for you since my hearing over 15k has been lost with age but I am very critical about high frequencies. Not that it is too much (usually too slow or rolled off) but simply not 'right'. There is some artificiality about it. What I have found out over time (double entendre) that it has to do with rise and decay of notes. Timing errors, phase, pre- and post-echos. Not with amplitude.

The problem is that conversion can be done in two ways and to confuse the issue further; a dac is not only the transition between digital and analog but part digital and part analog and the method you chose has consequences for the analog part as well (with current technology).
If you choose multibit, or R2R or ladder you might think you have to 'massage around Nyquist' (you don't actually *) but you can keep the analog part very, very simple (*) so that it doesn't get in the way of the music (ie no information loss).
If you choose single bit sigma delta you are picking up the sum of the fractures, glue them together and then you have to get rid of all the excess glue so to speak (that's the high frequency noise and smearing). DS chips are easier to fabricate due to looser tolerances but because of the high amount of oversampling you get a lot of HF hash and phase smearing. That impacts transients and that is what makes the unnatural sparkle in the high frequencies. You need a lot more filtering and you need a complex I/V and analog amplification stage that does get in the way of the music (information is lost).

If you convert over a ladder of resistors you need to calibrate them well but without oversampling (NOS) there is no unnatural pre-echo or pre-ringing. There will be some post-ringing but that is common in nature (except of course in Star Trek where they have 'inertia dampers'). There has been a lot of improvement in delta sigma dacs, especially in reducing this effect but I don't agree that even more filters will fix that. Actually, less is more and I'm back to where I arrived 10 years ago. (*) Better than new DS dacs (unless you play DSD where I'm not sure what sounds better).

As to physics and Nyquist, that's all very nice. In my experience that is very instrumental in developing a professional tunnelvision. It's always the same kind of people namedropping 'Nyquist this', 'but Nyquist', 'you don't understand Nyquist'. He might have been an engineer and physicist but his theory is more what we call information sciences. It's all virtual, not physical. And that's quite descriptive of the chasm between believers in scientism and people who believe their ears (just fill in the title of your favorite eternal flamewar and you see the two camps emerge). In the words of Chris de Burgh:
"And a chance to work it out,
For we cannot live together, and we cannot live apart;
It's the classical dilemma between the head and the heart;"

* after playing with a nice ES9038Q2M DS Dac that has all the modern features for convenience and a NOS, filterles R2R with only 1 resistor for the output stage I wanted to upgrade. I was looking at 2 choices: SMSL M400 (about the same as the A90) and the Denafrips Ares II. After lots of searching for reviews, opinions and comparison, with my experience in modifying and comparing dozens of dacs, I came to believe that the Ares was the better choice. And I'm quite certain that it is. Only when I compare the Ares to another good DS and my oldest dac, an R2R/multibit with 4 parallel vintage Philips chips that I bought for €45 10 years ago and I modified to the simplest form of output that is not according to spec, the outcome was very surprising. The oldest and cheapest and most limited dac (24-96 max) that I know measures like s#it won hands down. It has better space, clearer defined, highs are clean but detailed, it doesn't clip or saturate with soprano or piano high notes. And the bass is fast and clean too. It's not just the highs that are in order. And 'Nyquist' might say that I will get sidetones or spuriae but I haven't heard him play the hobo yet (used to tune a symphony orchestra).

Interesting and thoughtful response! I understand and agree with what you're saying about quantifiable and unquantifiable realms, also from a deeper philosophical point-of-view that extends to just about everything in life.

From Ken Burns’s Vietnam documentary:

“...in 1967, they went to the basement of the Pentagon, when the mainframe computers took up the whole basement, and they put on the old punch cards everything you could quantify. Numbers of ships, numbers of tanks, numbers of helicopters, artillery, machine gun, ammo—everything you could quantify...They put it in the hopper and said, ‘When will we win in Vietnam?’ They went away on Friday and the thing ground away all weekend. They came back on Monday and there was one card in the output tray. And it said, 'You won in 1965.’”

A hyper-focus on quantifiable "metrics" is often misguided. The ability to distill selected aspects of reality into numbers doesn't mean that the reverse process (inverting for reality from those selected numbers) is possible, or even plausible. Yet there are many technocratically-oriented people who don't get it, they think the numbers tell the entire story.

That being said, the ability to measure something consistently and reliably offers very practical benefits, and offers the possibility of having some kind of objective platform...even though the scope of that objective platform may be limited for the above-stated reasons.

I'd like to understand it all better...I'll work with the tools I have available, starting with some ultrasonic measurements using my Sony PCM-D100 recorder...I just need to find some time when the kids aren't around (it may be a couple weeks).

 

[sajunky]

In any case, I think this is something that Topping might be able to fix with a firmware update and addition of more aggressive filter(s) for those of us who are sensitive...so long as the hardware permits it (I don't see why not, but you never know). If so, that would be good for all concerned.

Demanding more brick wall from Toping is not going to make a case, I am afraid. They already use the most aggresive brick wall parameters with disregard of a negative consequences. Unfortunately none of the standard filters can produce effect you describe. Try other filters available, with a different algorithm. If problem persists, then a cause is not in filters, but something else. Try this device to compare using RCA output, it doesn't cost much, there is only one slow roll-off filter. When is done, it will serve you well on the road as well, it is a portable device. It is a safe purchase, as I/V conversion and output stage is passive, there is no possibility that Chineese crooks would fit fake opamps, as there is no opamps.

 

[JHern]

Demanding more brick wall from Toping is not going to make a case, I am afraid. They already use the most aggresive brick wall parameters with disregard of a negative consequences. Unfortunately none of the standard filters can produce effect you describe. Try other filters available, with a different algorithm. If problem persists, then a cause is not in filters, but something else.

Maybe, maybe not. I have not prejudged it. What I can tell you for sure is that, for the most part, the D90 output sounds immaculate through a variety of chains. In some cases, I'm hearing texture and timbre that is extraordinary.

The only issue is that it seems to aggravate my right ear, which is already subject to tinnitus. I treated my ears poorly as a teen, I think I'm actually lucky that matters are not much worse than they are. When I go to a live concert, the impact is a lot worse, my ears ring for days. And the squeal of a rusty bicycle brake on the street causes me great suffering. I am not the person to be judging this issue as the "typical case," my ears are weird, and abused, and I just want to understand what I'm hearing and what is happening and why. And if I need to get another DAC as a solution, I'm totally ok with that...these are easy to re-sell right now because they are sold out in many places, partly owing to the Asahi Kasei factory fire.

Try this device to compare using RCA output, it doesn't cost much, there is only one slow roll-off filter. When is done, it will serve you well on the road as well, it is a portable device. It is a safe purchase, as I/V conversion and output stage is passive,

I have plenty of devices that do not cause any aggravation. For some years I've been using a Marantz HD-DAC1 as a desktop amp, and it never fatigues. But it also has the Marantz sound, and it isn't aggressive in trying to reproduce high frequencies. In fact, I'm currently planning on keeping this as my desktop amp for now...though I might eventually pick up a Luxman.

there is no possibility that Chineese crooks will fit fake opamps, as there is no opamps.

My D90 was purchased from a super-hard core mega e-nerd shop in Tokyo, Japan. Those guys have torn it apart, swapped amps, studied everything meticulously, electronic components are their bread and butter, life blood coursing through their veins. In fact, they even offer an extended guarantee on this particular product, and they are super-enthusiastic about it. I trust them. The possibility that this is a matter of fake opamps is incredibly remote...

 

[Taz777]

So I was listening to a Tidal stream that started with Pat Metheny's latest album (very nice!) but ran off on a stream of consciousness to a bunch of other random tracks, and I had filter 1 selected on the D90 (it is the sharpest and most analytical around 20kHz). There was a tune that had a super high frequency resonance bell ring, and it really got to my ears. This doesn't often happen with other DACs, and I was impressed, as well as disturbed, this was one of the first times I've had that happen through a virtual audio source. Is it the Tidal track? The MQA compression/folding (I'm skeptical of this format, but it could have some weird artifacts)? I don't know. I'll have to keep listening and comparing. But I hope that Topping can come up with some more filters, via a firmware update, giving us more options. Or is it limited by the chip? I don't know.

My understanding, which could wrong of course, is this:

The filters for the DAC are provided by the DAC chip (AK4499 in the case of the Topping D90). These are the fixed, user-selectable PCM filters for non-MQA datastreams (PCM and DSD). MQA songs will have their own filter encoded within the MQA datastream, thereby programmatically generating a 'custom' filter per MQA track in the D90 (or any other MQA-capable DAC).

In theory, MQA songs will override any filters you have selected via the D90's menus.

Could you clarify if you were listening to a regular FLAC (PCM) song in TIDAL or a Masters (MQA) track? If the former then your D90's filter setting will apply, otherwise the Masters track will provide the definition of the filter to be used.

Happy to be corrected on my understanding as I'm still learning...

 

[sajunky]

My D90 was purchased from a super-hard core mega e-nerd shop in Tokyo, Japan. Those guys have torn it apart, swapped amps, studied everything meticulously, electronic components are their bread and butter, life blood coursing through their veins. In fact, they even offer an extended guarantee on this particular product, and they are super-enthusiastic about it. I trust them. The possibility that this is a matter of fake opamps is incredibly remote...

I tell you a story. Many years ago having electronic background I was tuning CD players, similar what these guys are doing. On one project I heard a hint of occasional artifacts, not a large amplitude and generally I was happy with result. When I brought it from a lab to living room, a cat that was normally assisting me on a coach started to protest on the same songs and was running out... repeatedly. I took a player back to the lab and found that certain tests triggered ultrasonic oscilations. Normal frequency sweep didn't show any abnormal behaviour.

 

[]eep]

Maybe, maybe not. I have not prejudged it. What I can tell you for sure is that, for the most part, the D90 output sounds immaculate through a variety of chains. In some cases, I'm hearing texture and timbre that is extraordinary.

The only issue is that it seems to aggravate my right ear, which is already subject to tinnitus. I treated my ears poorly as a teen, I think I'm actually lucky that matters are not much worse than they are. When I go to a live concert, the impact is a lot worse, my ears ring for days. And the squeal of a rusty bicycle brake on the street causes me great suffering. I am not the person to be judging this issue as the "typical case," my ears are weird, and abused, and I just want to understand what I'm hearing and what is happening and why. And if I need to get another DAC as a solution, I'm totally ok with that...these are easy to re-sell right now because they are sold out in many places, partly owing to the Asahi Kasei factory fire.



I have plenty of devices that do not cause any aggravation. For some years I've been using a Marantz HD-DAC1 as a desktop amp, and it never fatigues. But it also has the Marantz sound, and it isn't aggressive in trying to reproduce high frequencies. In fact, I'm currently planning on keeping this as my desktop amp for now...though I might eventually pick up a Luxman.



My D90 was purchased from a super-hard core mega e-nerd shop in Tokyo, Japan. Those guys have torn it apart, swapped amps, studied everything meticulously, electronic components are their bread and butter, life blood coursing through their veins. In fact, they even offer an extended guarantee on this particular product, and they are super-enthusiastic about it. I trust them. The possibility that this is a matter of fake opamps is incredibly remote...

I think you misunderstood sajunky, he was talking about an 8x TDA1387 dac that does not require opamps since the TDA already have high voltage output.

But the problem is, we really do not exactly know how hearing work. We know about hammer and anvil, cochlea and sensor hairs but little about the nerves and connection to the frontal lobe of the brain. Like, how can you be (over)sensitive to supersonic noises at an age where you usually can't even hear 20kHz anymore. So you're in uncharted territory to explore.

I would suggest to try either NOS and non-filtered or maybe exactly opposite brickwall filtering. Or go (oversampling) to >96kHz and use a slow filter so you know you won't have ~20kHz-30kHz artifacts.

I think your goal shouldn't be to not be aggravated but to enjoy (duh). I think your best bet is to go R2R and tubes. And speakers io headphones. And not dometweeters that struggle to get to 20kHz but proper tweeters that can do it with ease (and no stored energy, breakup or resonance). Not all dometweeters are bad but to me most share a certain 'sound'. Often it's a lackluster filter but most dometweeters just don't cut it. Same goes for most headphones that are simply dynamic full range drivers. You can get great sound that isn't just satisfactory but really awesome. High end is kind of the search for nirvana (in a philosophical sense because it's the losing of self and desire and restraints instead of heaven being the self in the way it was initially created, thats not going to fix your problem on your own).

I like your philosophy about numbers. Yet there is an exception that can create reality from numbers. Its called 'life' by means of DNA which is in fact stored information and algorithms to reproduce and recreate. And some (thinkers/scientist) say that the entire universe is a digital simulation. But that doesn't really help the case of the flat-earther number fetishists (because: who's doing the programming then?).