I opened up the Topping A90D Headphone amp. Here's what I found.

Some people have been claiming that the Topping A90D is the best headphone amplifier you can get, beating even more expensive products. But what's the truth? I took at look at what is actually inside. I also compare it to the Singxer SA-1 and Soncoz SGA1, as well as higher-end gear, using a variety of headphones, such as the Dan Clark Audio (DCA) Stealth, Expanse, Final D8000, Meze Elite and others.
Thanks to APOS Audio for sending me one for review. You can buy it via this link, which supports my channel:
www.hear.audio/go/a90d
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00:00 Start
07:47 Inside the A90D
13:51 Sound
21:43 One final thing...

[@WeeWeeJumbo]

just wanna throw a big Thank You to the community, who have provided so much useful information over many years. you've enriched my whole audio life

[@mfgillia7606]

Great review - especially taking us inside the box and describing the different components. Very informative and interesting.

[@narayananmmenon339]

I appreciate that you made this video. You took the time to sit down and explain the technology we are spending money on. Thanks! Any recommendations for tube amps in the same price range with similar detail retrieval?

[@Chuckster0]

Bravo! Fantastic video! Thank you for explaining that you can have a highly resolving amp that has high distortion. I bet the Studio 6 sounds magical.

[@jackcolo1601]

Great review as always.

[@Currawong]

I don't know if I should be disturbed that I've had to put all comments on moderation for this video. A number of people flat-out posted abuse because, even though I said it's a good amp for $500 (actually $599, my bad) it clearly, to me, doesn't resolve as well as other amplifiers I have here.

[@motjones2341]

If a less well spec'd amplifier sounds better that does mean you prefer a less transparent to the input signal amplifier, there is no argument possible with that. Many share your preferences. Switching power supplies are in the highest end gear, and the highest spec gear as well, that is a fact. The life span of switching power supplies probably will not exceed "simple" linear supplies but power transistors in the amp outputs and in the power supply regulators in more sophisticated regulated linear supplies are common failure modes never the less in most amps I serviced years ago. Never the less, I do agree that switchers are run hard and will purchase one or two spares for my A90D as I intend to keep this unit for a long time as I prefer transparency to the input signal and I listen to this unit for hours on end with no fatigue, to me this amp is serious value for money like I have never seen before. When used conservatively it is inaudible as proved by the measurements as far as replication of an input signal goes.

[@Currawong]

Which high-end brands use switching power supplies? The only one I know of is Linn. It's notable that a number of important measurements, such as IMD, and the slew rate, are missing from any measurements online, along with the analyser settings alongside any others. From what I've seen of amps and DACs from Topping, their IMD levels are higher than their THD levels, yet no mention of this! Also, the distortion figures are for outputs far over what would at least destroy your hearing permanently, if not the headphones. If you look at the graphs to the levels within what people might actually listen, the harmonic distortion levels are within what is considered "audible", if only barely.

[@motjones2341]

@@Currawong Do you consider Chord or Jeff Rowland high end? Chord ulitma 3 ($9K), ultima 5 ($15K), Jeff Rowland almost all his power amps ($$$) use switching power supplies, just to name a few. Topping A90D CCIF IMD 18 and 19K is -118, IMD 4 to 1 (60hz and 7 Khz) is -110. I agree that at extreme low levels , ie IEM levels, distortion is probably barely audible in the quietest rooms and the very, very best of ears. Anyway, if I had the AP test gear, I would delve down to lower levels as well and on real loads to really tease out the capabilities, but good luck finding any high end manufacture publishing this kind of info so we can only work with what we have, and Topping is close to or at or above SOTA compared to most high end gear with the specs that are published. I think if Benchmark would put lower powered version of the amp circuit they have in their power amp into a headphone amp Topping would need to up their game, but at $3.3K their existing amp can not overall exceed the published specs of Topping at $600.

[@Currawong]

Did you watch my review? Did you see the Chord TT2 and MScaler on my rack? You might have forgotten where I talked about how the TT2 uses super capacitors. Aside from that, the Chord designs use methods to specifically mitigate the effect of the power supply. On the other hand, a good example of a low-THD design, such as the THX AAA 789 -- you plug a capacitor bank between the DC power supply and the amp and the sound changes... because the PSU is rubbish. Focussing on low THD and SINAD *does not represent better performance*. It's a marketing sham, and I've had a bunch of people try and gaslight me in the comments over my refusal to buy into it.

[@motjones2341]

@@Currawong Look, I just answered your questions with specific examples (" Which high-end brands use switching power supplies? The only one I know of is Linn." ). Earlier I said that you preferred amps that distorted more, and I understand many do, no big deal, I enjoy, when I want to, my SET amp, I am all right with your preferences. Yes I watched your review, and there are a lot of generalities in there which is fine but not much factual stuff to directly engage you with, except measurements, which are facts. Even you pointed out how Topping uses wire components (atleast you assumed they are acting as filters) to mitigate switching artifacts. However, the SINAD shows that any affects of these scary artifacts are below audibility. There is not a problem there to be solved with an external capacitor bank, be it super caps or electrolytics or oil or whatever. Does changing the nature of components in an amp affect the sound, sure, does that affect get the amp closer to amplification without alteration , without measurements one will never know. I will bow out and let you get on with your listening impressions and theories as I think you do try to stay as balanced as you can within your understanding of electronics which is all I would hope to do as well if I were in your shoes. Best wishes on your channel in future.

[@brendanliddell240]

Thanks for the review. I see the Gustard R26 in the video 😁 eagerly awaiting the review of that. If comparisons could please be made to the Denafrips Pontus/ Venus as they're the competition I'm considering. FYI, the Gustard H20 Pro will be released next year which aesthetics perfectly match the R26 for a stackable set. Will be keen to see reviews of that also once released.

[@chungang7037]

0:21 shots fired! and I totally agree~

[@mikeg2491]

ASR guys remind me of the CRT hobbyists who obsess over screenshots of scanlines and constantly chasing visual perfection instead of playing or enjoying the games

[@hamishthecat4370]

Nice to hear quality references to the GS-X Mini as I recently bought one to power a pair of Audeze LDC-X cans. I was very pleased with it's preamp capabilities driving my NAD bridged amps.

[@juanmillaruelo7647]

Thanks to your contribution to audio. I do believe in the free flow of information in civil and polite terms.

[@MrKeech666]

Great review as per usual! 🤟😎

[@Casperwinde]

Very good and honest reviews ❤

[@almyp]

Thanks! I’ve waiting for this one. What would you recommend as better options for the Expanse? In general, comparison to gear at higher price ranges would be highly appreciated.

[@SpykerSpeed]

I own the A90D and I prefer the Schiit Jotunheim 2 over it. In my view the A90D produces a flat wall of sound compared to the more musical/dynamic Jot 2. I also prefer the warmer/punchier bass of the Jot 2.

[@kdb424]

I've likewise had both to listen to back to back and far prefer the Jot 2 for the exact same reasons. The Jot sounds much more like you are there with the band than listening to a recording, which I feel is honestly the goal of higher end gear, and it's a lot more engaging to boot.

[@KAL-589]

Interesting. I appreciate this video. Many in the Audio Science Review site bash Burson Audio products for their low thd numbers but all the reviewers that review the sound love the sound.

[@HiFinca]

This is the best audio review I've ever seen. And I watch them all.

[@ladevinette]

Thanks for your review , I was planning to buy it but after your review and some more search about the sound quality , I change my mind and I’ll go for VIOLECTRIC HPA V202 😀

[@kato2395]

If measuring right doesn't make the music sound good, then I don't need it to be right

[@audiobean]

Excellent on details this review, very interesting ! My question, a little off topic: Would I risk DC offset from a Topping E50 DAC connected to my SA-1 put in bypass mod ? Either through RCA or XLR ?

[@shawnpwatsons1]

Very good. Thank you.

[@juststuff5216]

I've owned a few Topping amps before, and found them to be 'meh' at best! Lashing out £600 for this, is not exactly floating my boat.

[@edwardbit8225]

I have Topping Dacs and amps,they measure well and sound well,tahnsk for the review.

[@revelationsoundstudio]

You provides the best review of this headphone amp. It was educational and very insightful. Thank you so much. Some videos say Best headphone amp out there and your like well several people said the same thing, it must be true. Best THX amp would be a more accurate statement. Seeing the wall wart lower supply with the filters remind us higher end headphone amps are better for a reason. With thst being said, it was impossible to get this quality at a consumer level in the past.

[@chrisharris1522]

When ever someone says that something subjective like audio is the best then just disregard that statement, they are either being dishonest or just did not choose their wording very well. This is an entry level amp for people wanting to get into the hobby and reviewers that make such wild claims or attempt to compare to high end equipment without making this clear are misleading their viewers. Edit, I feel I should elaborate on why I think this is a good option for first timers, It really boils down to versatility, with this amp the sound quality is pretty good and there are no constraints on which components this can paired with, making upgrade paths about as simple as it can be, and if you do not like how it sounds you haven't wasted thousands of dollars on an amp that does not fit your personal tastes.

[@xyanide1986]

I'd love to hear your thoughts on the Rupert Neve RNHP, I really liked it at a demo.

[@whocares0503]

I was using a Cavalli Liquid Carbon 2 and I bought this from Apos. I am really enjoying it. Sure there may be better but I am happy anyway. It beats my Liquid Carbon 2 hands down and I will be good for awhile.

[@negserg7639]

I am the owner of smsl sp400 and also tried to buy topping a90d and listen to it for several weeks. I did not find their comparisons on the Internet, so I hasten to share. To my ears, for some reason, the sp400 gives the best highs and also has better detail. Even though the topping has a fatter sound overall, I like the way the sp400 draws the bass more. Especially the subbass and lower end, below 150hz. In general, I get more listening pleasure from the sp400 and it fits better with my dan clark expanse in sound, which is especially felt when listening for a long time, and not just comparing some parameters in a / b testing. I have tried other famous amplifiers like ferum etc. I also like them less. On the Internet, you can find a mention of the fact that the a90d has a cold sound. Actually the sp400 has a (more?) cold sound in fact. But I would compare this feeling to the feeling of the morning after the rain or something like that, its sound is fresher. And it's definitely a better fit for dan clark expanse. I gave my friend a comparison, without saying which amplifier and its conclusions were the same. When comparing the amplifiers, the output volume level was set with a voltmeter, so we can definitely say that the difference is audible. The DAC that was used to compare smsl su-9 pro. I also have a gustard x26pro, with it the results are exactly the same.

[@bobcoco6047]

Thx for the input, indeed comparisons between those are quite rare, & from what I read about 'em, I got the exact impressions you shared, which is funny to me ^^. The "feeling of the morning after the rain" was ... "sparklingly interesting" , & just keeps showing to me how meaningful the link between certain fields (sound / image / feelings here) can be. Still currently on the SP200, coupled with a SU-8, & ending on a DT1990 then recently a Focal Clear OG, I'm looking for (how surprising xD ) potential upgrades, & even though I sometimes feel like warmness could be appealing to me since I've been rather distant with it previously + it's lacking on such source pair, I still mainly believe I'm not afraid of that coldness, as long as I can enjoy those subbass, better highs & detail you mentioned. (I'm a ~ U-shape guy I guess) It's just that considering what Curra mentioned, I might be missing the main game going that way, since we're still focusing on the specs-sheet brands, that put out ridiculous amounts of new models, which isn't the best sign of refinement of each product... (Here I'd say I'm + of a Sniper guy than machine-gun one)

[@x-techgaming]

I have an A90D now, used A30 Pro previously. I tried SP400 and found it quite dull, even dark, sounding. Returned it right away. Had an excellently dark background, though. I have no complaints with the A90D, but it's gonna take something like a GS-X Mini to really out-do it, I suspect.

[@nelsongracia]

I have smsl sp400 , use as a preamp for my 3 crown class D amplifier. i made my own jbl 3 ways speaker, and the class A amplification of the smsl sp400 help in the highs with the class D that is base on bass power and clarity. Looking for a better class A preamp to raise my level , but with reviews like this is not possible. Listen to a headphone is like listen to only 1 way of the 3 ways speaker system . Smsl sp400 is a joy to own it .

[@wokthetalk3079]

Thank you for the review, I like it when you take off the cover and explain the design behind the build. I’m hoping GaN FET class D will make its way to headphone amplifier design and manufacture. I see you have a R26 in the background. I’m leaving ok’ing forward to your review of this DAC. I was wondering if Gustard’s H20 headphone amplifier would pair well with the R26. Can I ask you to please also review the Shiit Lyr+ headphone amp , there appears to be 1 KZbin review on this device by Wave Theory…. Ty

[@Currawong]

There is absolutely zero point in having Class D in a headphone amplifier, so I don't think we'll ever see it. I plan to do a lot more Schiit products, but various things delayed me this year. Hopefully in the beginning of 2023.

[@Ezees23]

Hahaha, a subtle but valid dig at ASR. I love it, LOL.....

[@milosCivejovidar]

Good review. Somebody needed to say this. For some time I was following the Topping/SMSL line of products and then realized that they are just targeting the PC enthusiast market, comparing Megahertz's and Megabytes to Output Power and Distortion. Topping and SMSL just produce to many new cheaply designed products per year with widely available components and they don't have any staying power because the internet influencers constantly pushing the newer lines of products. I do respect some of the other brands from China like Fiio, Aune, Gustard and Audio GD.

[@alphaniner3770]

Indeed - when a market releases new products at an alarming rate - people should ask themselves what the consequences of that are. The sound of these Topping amps is reasonably fine, but they are relatively cheaply made and will probably not last too long. Also people that feel the urge to jump on every new hype train will be kept busy.

[@Ezees23]

I bought a used Gustard H20 headamp to compare with the OG A90. Needless to say that I still have the Gustard and the A90 went away as soon as I could get it into the mail. Even my cheaper discretes were better......

[@andypeterson9630]

What you hear and what you experience are two different things. I’ve spent enough time in anechoic chambers and at different atmospheres to welcome the return to ambient norms. Many applications call for signal and acoustic isolation but they’re purpose driven. I wouldn’t want to dwell there. This review has value well beyond a particular brand or model. Many thanks!

[@mopnem]

This is the most comprehensive review I’ve seen on this product, will have to check out the channel. Currently my amp. Was able to compare to a far more premium amp & preferred the a90 so don’t know what to believe. Could just be a preference for tight, leaner & as much detail/texture as possible over other things..Great point on the D90 picking up noise, to me it was too sketchy without a getting the right cables & such

[@SimpleMailWork]

Thank you!

[@vagomaniac]

Nice analysis, sir. Did you try this headphone amp with this R26 dac ? an idea in two words for this dac?

[@Currawong]

I haven't, as they arrived and were tested at different times, but I will for the R26 review.

[@vagomaniac]

@@Currawong Ok then. I hear there’s a hype about this dac, and maybe some exaggerated remarks too. Gday

[@inscythe]

I have the A90D, after upgrading from A90. To be perfectly honest, it is not the best sounding amp for pure enjoyment in my opinion... That honour goes to the Burson Soloist (or Conductor) 3X GT. But that's completely different price range and target sound. Burson is definitely catering more towards audiophile sound, while Topping has always been targeting a more reference sound. However, I went with Topping A90D in the end because of the pure hardware prowess that it provides at this price point. Sound tuning and preferences can be adjusted later on with EQ or other digital filters in my opinion. I always think that Topping products are the budget versions of pro devices like RME. Regarding Topping amp blowing up headphones, as far as I know, it was only happening in one product line, which is the L30 and it was rectified soon after. I don't thinkTopping has a long track record of such things, but I understand that one blown headphone is one headphone too many, and trust is difficult to reclaim. However, I don't think anything similar has happened to any of Topping lineup after that. It's probably why their new lineups are very aggressive at power protection (like the earlier firmware of A90D cutting out power when plugging SE headphones, or DX3 Pro+ just outright turning off with some planars).

[@mfgillia7606]

Plus there are also examples of high end amplifiers with linear power supplies blowing up headphones. In the two cases I'm aware of the manufacturer quickly resolved the issue and in one of those they essentially gave the customer a free $2,500 amp. So accidents do happen and perhaps more important is how they handle it...

[@Ezees23]

I ditched the OG A90 as soon as I heard it beside my Gustard H20 discrete Class A amp. It wasn't a subtle change......

[@juanmillaruelo7647]

Differential (balanced) driving allows more voltage and power delivery to insensitive headphones such as some planars. The A90 provides up to 7 W in balanced mode and 3.5 W in single ended. I use the A90 and drive my Sundara with single ended cables without a problem and very good results. There is no need to use a specific SE amp design such as the L30ii (the simplest Topping amp). The A90 gives you more flexibility and headroom.

[@x-techgaming]

So GS-X Mini is the next upgrade from my A90D? Got it :) I have no complaints about the A90D, except that you have to use the remote to change gains(which I've never needed to do yet).

[@adamjohari]

I have a chord mojo2 as a dac and plug it into my thx789 to hifiman arya. Could you recommend an amp? Below 1000usd hopefully. 😅

[@SkywhiteChannel]

I have a few setups at home, my high end system is a woo wa33 elite, holo may L3, aurender n200, my mid range is a chord TT2 and mscaler. My low end is the topping D90SE and A90 discrete. My hearing is not what it used to be, hence my observation may not be valid. But the Topping combination surprised me. I still prefer my main setup but the chord stuff doesn’t impress me anymore. I probably need to listen some more and I suspect the ear infection I had several weeks ago may have affected my hearing because nothing sounds as great as it used to. Just goes to show you how subjective this stuff can be.

[@adriankasa4339]

When I opened your video, suddenly I thought that, what the... Tom Hanks has become an audiophie!!!!

[@immm2m]

I hope we can see a A90D LPS mod! This can be a good comparison for all these flagship Chi-Fi dacs & amps. They all seem to use the same power supply. Topping, SMSL etc...

[@TheBobby1kenobi]

is the rca input on this an analog input ? I wana use this in my chain after my GoXlr interface and it provides an analog out 3.5mm so i was thinking about a 3.5mm jack to rca cable.

[@pascalaspirot1821]

I bought the D90SE that I use in USB and the A90 Discrete and I also bought the TCX1 cable that I plugged into the 2 devices so how do I plug in after RCA speakers? the speakers on the D90SE or on the A90 Discrete another question I have no sound on the A90 Discrete when I plug in my HIFIMAN why

[@jlemaster1157]

Great review and highly awaited- good on ya. I have A90D and the Burson 3XP (about twice the price). I agree with all your sound impressions shared here. I find the Burson (which measures not as good per ASR et al) to project a deeper soundstage and better imaging/separation vs the A90D wide ‘wall of sound’. Connecting an inexpensive Douk Audio P1 preamp with GE JAN L5654w tubes between the amp and a DAC (i have used the Topping D90SE and also the IFi micro iDSD signature) does improve the sound quality (moving A90D from more analytical to a more musical/mellow sound). I like A90D but find I am using the Burson most of the time and the A90D less and less.

[@fabianmilitzer7712]

Hi, where can i get such a nice headphone stand like yours? I mean the dark brown one that has the Sony headphones on it.

[@SimpleMailWork]

Review the Gusturd R26 plz, I saw it in your background

[@klewja]

I have unfortunately sold my LCD4 and Abyss 1266TC. I would love to try them off my Dan D’Agostino M400 monos and the HD PRE with my MSB discrete. The best I ever heard the Raal was off a Dan D’Agostino momentum integrated amp. That was a $42k amp. Imagine with 400 watt monos and a $42k pre. 😊

[@bensolorio76]

Good review as usual!

[@tradfi950]

doubt that the "low sinad" and "low thd" makes it sound "cold and analytical" all measurements suggest that the amp would output the correct signal from the dac with no audible changes. i have a feeling that if topping products were never measured and didn't have the reputation, this video would have gone very differently. switching power supplies are not necessarily worse as well, as linear power supplies do have mains leakage, and measurements also show that the differences in noise in decent switiching and linear power supplies are far below the limits of hearing. good coverage of the product's insides and general usability though.

[@Currawong]

Good points.

[@mfgillia7606]

The proof is in the pudding - go listen for a few hours comparing Toppings low sinad products to higher end options like Oor Hypsos, Bliss and others then see what you think. I own the Topping A30 Pro and to my ears the Topping was great! Until I was begrudgingly forced by friends to listen to other options...

[@kutokuro538]

It’s like judging an athlete based on their height, weight, etc. Yes they offer a bit of insight about who’s better but you’ll never know for sure until you see them play on the field

[@mljenkins7913]

I was wondering what gear and data you’ve used that has led you to this conclusion? This isn’t meant to be a litmus test question just, what pushed you into this line of reasoning?

[@tradfi950]

@@kutokuro538 more like judging an athlete based on race timings. unless you can quantify what makes an electrical output sound good or bad that isnt noise, thd or imd, it's hard to take listening tests as the best test given subjectivity of human senses which can change day on day

[@CML21]

Another great review - thanks for doing it! I have an A90D, and I also have issues with the volume skipping 20+ levels via the remote. I'll try the firmware upgrade you mentioned, but if that doesn't work, I'm a little nervous about using it... that thing has too much power to have an issue like that. Thanks again!

[@kyleo2113]

I didn’t have this issue with my a90d but If is a big concern you can change the power curve in the settings so it limits the total output

[@tomas_m]

Is it possible to select only a single output? I'd like to have 2 differently sensitive headphones connected (don't want to wear out the plating on the jack), and use the less sensitive pair without the other blasting music.

[@dr.donath]

Nope, L70 everything can be played at the same time and everything can be used solo.

[@Berkanann]

How much better the GSX-Mini is compared to the A90D and Singxer?

[@jimatyeo]

Sadly after purchasing this unit after many glowing reviews, I have found its not that special. AS some others mention it is better than my 789 but it it doesn't sound better than my Feliks Audio Echo II or my Schitt Audio Lyr III. Plus I also bought the D90 DAC it worked properly for about 2 months and then it started to only work intermitently. Tried my best to get in touch with APOS to no avail until maybe 3 months after that I finally got an email from them saying send it in. However by then, since it had not been working a friend of mine who repairs computers and plays around building audio gear said he would take a look at it. So months later it is still in parts on his work bench and that feels like I threw my money right out the window. Will never buy anything from Topping or Apos again. If I get the urge, I will instead just throw my money out the window and cut out the middle man.

[@WhenKittensATK1125]

How did you disassemble the case? It looks like it has two ribbons connected to the front panel, so I couldn't fully remove it. I bought an used one and I can't change the volume manually without the remote.

[@Currawong]

I disconnected the ribbons. As they can't be replaced easily due to their short length, I bought two new long ones of the same type.

[@vaneast411]

Thanks!

[@Currawong]

Thank you very much!

[@dhg1839]

i have always had trouble with Topping products, personally i would not risk buying another

[@4epa1012]

Hi Currawong, Are you planning to review the Aune S9c Pro DAC/Amp and Aune S17 Pro amp anytime soon? I would love to hear your thoughts on these products.

[@Currawong]

The S17 looks a little interesting, as it seems to have a linear PSU rather than the cheap switching PSUs Topping likes to use. However, they are fudging their power figures. The S17 is definitely not Class A all the way out to 7W. It may not even be 7W RMS, but peak. If it isn't overburdened with soundstage-depth-killing negative feedback for the numbers (and it has a 5V output, obviously ideal for the APX-555 measurements, and they only state the 1kHz number, which is useless) it might be quite decent.

[@4epa1012]

@@Currawong Thanks for the reply! I might go for the S9c Dac/Amp combo to replace my Ifi Zen Can/Dac Signature V2 setup. It seems to be a decent AIO unit that has a linear PSU too. From what I see in the reviews it has a really good lively sound with wide soundstage, as opposed to the dry Topping sound.

[@mrjohnsuen]

One example is Pass Labs HPA-1 which ASR has done its usual measurement on. According to ASR, nothing is good (incl. HPA-1) except those from Topping and the likes who scores well on SINAD, THD, etc. According to Bob Katz who reviewed the same amp, and he finds the HPA-1 excellent and he's no hesitation to use it for mastering. In a nutshell, the audiophile world that ASR lives in is one that life is simple, a few basic, snapshot tests can absolutely tell if a guy is holistically good or bad. For those who may not know ASR, its a forum that pride itself with those SINAD, etc that Currawong mentioned in the vid.

[@kutokuro538]

IMO there might be some aspects that aren’t measurable by our current technology that contribute to the sound quality making some “better” amps actually sound worse than the “worse” amps

[@harisjaved1379]

Not really, they reviewed many chord units favorably.

[@harisjaved1379]

@@kutokuro538 wait…no…nothing is magical about sounds or waves. We can measure everything about them, unless we are talking about gravitational waves or relativistic physics.

[@Maver1ck911]

Is the SA-1 jumper mod worth the peace of mind you won't kill a 3k USD or above headphone?

[@eLcHiNoChannel]

I am new to audio equipment. I recently started with the LCD-XC and the baby stack from Shiit (Modi, Magni, Loki). This amp is popping up in many reviews. Wondering if I made the right choice with my first budget friendly setup.

[@gabrieljung6763]

that baby Schiit stack is always a keeper!

[@eLcHiNoChannel]

@@gabrieljung6763 Thank you! With some many options and just getting started on this hobby, I wasn't sure I made the right choice.

[@g-mail4743]

Such a great review, thank you. I own the A90D, I am an electronics guy, but don't have your background knowledge, so I greatly enjoyed this review. I like the A90D alot, its perfect for me who watches youtube videos, the news, and movies alot. I find it better than my old L30 to an extent being that I filter my incoming power. I own the Cavalli Liquid Platinum as well and I find the two amps to sound quite the same with the CLP maybe being more natural and the A90D being a fuller sound. Great review! thanks!

[@spiritualarchitect4276]

The A90D comes pre-set with BOTH the Preamp and Headphone Amp ON. How do you change it so only the Headphone Amp (HPA light) is ON?

[@Robert-ci6sj]

tbh I don't get what punchy sound even means when it comes to the A90D. I had it for a week and compared it to my RME ADI-2 Dac fs and the ADI-2 just wipes the floor with the A90D throws it in the bin and never looks back. It's seriously a difference of having foam plugs in your ears when listening to the A90D with for example the HD800s and pulling the plugs out once you go to the ADI-2. So much more sound stage, precision and details in the highs that is almost insane. The Topping had a slight edge when it came to certain bass tones but literally only that. All in all the HD800s became a completely different beast when connected to the ADI-2 and really disappointing when connected to the A90D. If people who only listened to the HD800s on a A90D think that their soundstage is huge and resolution insane, they have no freaking clue what those headphones are actually capable of - and i can't think of a reason why it would be different for other headphones.

[@memeswillneverdie]

I’ve got a pair of LCD Xs and im a sound engineer looking for an accurate reference sound with no extra colouration and to have as accurate a sound as possible, would the topping A90D suit that use case? It may not be the most pleasurable amp for audiophiles but I’m looking only for precision and accuracy.

[@Currawong]

I'd say so.

[@memeswillneverdie]

@@Currawong fantastic, I’ve been trying to look around for alternatives since there are quite mixed reviews, I’m getting a gesheli labs j2 dac and running balanced with a spdif input from my audio interface, From what I’ve seen the j2 is very precise and neutral while still being fun to listen to, would you agree with this assessment (the akm chip is the chip in planning to get)

[@Steve0310]

Thanks for the review. It was very interesting that you took the time to open the unit up. I'm not really a huge fan of the Topping/SML stuff (for that matter a lot of the THX stuff falls into the same category). A lot of that stuff sounds lifeless to me (flat, boring, sterile, etc). I judge equipment by listening to it, not by it's THD/SINAD numbers. I Have the Hifiman HE6se V2 and bought a Hifiman EF400 to drive it (on sale for $499). I think with the R2R DAC inside it does a good job (excellent bang for the buck). I also ended up buying a XDUOO MT-604 (on sale for $143 from Apos).to hook up via Balanced Cables to the output of the EF400. The funny thing is even though it's rated at less power, it seems to have at least as much, if not a tad more. Long story short, I love it as a whole package for under $650. I can use a tube flavor if I like or just use the EF400. Very happy with that set-up.

[@danielbrown2715]

Superb review, the inportance of power supplys can't be overestimated, i have a Project Headbox RS , i upgraded it by adding Project's optional power supply which i thought was expensive at £450 however it made a substantial improvement to the sound.

[@force330]

I own a Topping A90 pair with Hifiman Arya SM. Really enjoy to listening them. However, I am always thinking about as a Headfier. I can only upgrage one thing, Arya or A90. I felt in love with LCD5 & Meze Elite but I am also worry about I cannot push them to their normal performance with the A90. Or I sould upgrage my AMP first.

[@Currawong]

Headphones should come first. You can work out the rest later.

[@joanyadhatan]

4:11 😳😰😓 😅 very nice review though, thanks!

[@jazzandcocktails7]

Why I switched to Audio-Gd from Topping....

[@chungang7037]

Who hyped up balanced connections ?

[@mfgillia7606]

I was curious about that too - i.e., which one person single handedly caused balanced connections to become the standard for a large number of dacs and amps.

[@xyanide1986]

I dunno, studios?

[@Currawong]

The old HeadRoom (used to be at headphones.com -- see the Wayback Machine). Tyll made a balanced amp using two SE amps re-wired. It was called the Blockhead.

[@razisn]

I believe the comment was about balanced differential topology not balanced connections.

[@alphaniner3770]

I had a Topping A90 (not the D, that seems to be a slight upgrade) - and at first I was blown away by it's performance. But then after a few months I realized that I was never listening longer than about 20 minutes - I was switching tracks and albums all the time - I was getting restless and was never really drawn into the music. I guess that I was missing the life in the music, or perhaps I couldn't step away from critical listening. I now have 3 other amps, one cheaper, one more expensive and one the same price that I all prefer above the A90. That's why I sold it.

[@ariam6168]

If you have 3 amps doesn’t that tell the story? You’re a consumer audiophile always chasing the next best thing. No shade, just saying. You’ll sell your current selection like you did with the topping as soon as you get the itch again to “upgrade”

[@kato2395]

Same experience with my E50&L50 combo. Well said. I also stop listening to music after owning it for a few months.

[@kato2395]

Also do you mind naming those 3 amplifier that you enjoyed more than the a90d? The cheaper, more expensive and same price ones?

[@Currawong]

I see a tube amp in your future. :)

[@alphaniner3770]

@@kato2395 yes, the cheapest is an Audio GD r2r DAC/amp, middle is the Singxer SA-1, and then a Kinki Studio Vision THX-1. I know that the brand Audio GD is bashed by quite a few, but I really like it, and it's quite cheap compared to the competition :o)

[@suryapratamak1690]

Excellent breakdown. I really enjoy it. i have a90d and wells milo. I still prefer milo overall. But a90d is also very good amp with my warmer headphones. As you sayed, detailed and punchy, and i noticed no glare in the treble. But you mentioned power supply of topping, an you may be right. If topping could have an option for outboard linear power supply, i think the sq can be elevated still.

[@donniedarko5529]

Would something like a mojo2 into an a90d, help the Diana V2 and HD800S scale and get the most out of them(without going crazy budget wise) ?

[@Currawong]

A Mojo 2 will drive a HD800S fine. Not sure about the Diana, though on specs alone it'll work. The Mojo is quite capable, probably more so than people realise.

[@ahmedsafa91]

got for 200 dollars so no complains.. yet the timbre of the sound is little colder than my taste. but it suits well with warm headphones and dacs

[@wangmingchu1379]

Running the d90se and a90d stack for a month and I love it. I use them as my pc DAC/amp for media consumption so far really enjoying the combo with stellia. Just finished the Callisto protocol and it was a great experience

[@spiritualarchitect4276]

I have been using the A90D with my Stellia too. I think I need the D90 because my bass is lacking on older CD's. I added a Lokius but that did not help much. Question: The A90D comes pre-set with BOTH the Preamp and Headphone Amp ON. How do you change it so only the Headphone Amp (HPA light) is ON?

[@afrancois1968]

I have a A90D and it’s a substantial upgrade compared to my 789. I planned to upgrade the cable that came with my Focal Clear MG pro to a balanced one, good to hear that would be a good idea. I find it hard to believe that other amp’s would give more details, there’s tons of it. The A90D is connected to a Hegel P20 and Gustard X26 pro. All is connected using Sommercable Epilogue. Very good cables for the money. Had wait two month for deliver of those cables…

[@Currawong]

The Law of Diminishing Returns certainly hits hard above this price point.

[@WillieBloom]

Hi Alain. Do you have any hard-to-drive planars like the Hifiman HE6? I own the HE6SEv2. I purchased it on holiday and with me i had the Ifi iDSD Signature. It can drive the HE6's but it pushed the unit to its limits. Turbo mode, plugged in, gets quite warm but sounds good. Then I plugged the HE6 to my THX AAA 789. No. Just no. compared to the little DAC/amp that could (iDSD Signature) the Drop amp sounded flat and boring. Like its soul was dead inside. So I'm curious to hear from other audiophiles if they have hard-to-drive headphones and an amp like the A90D or something similar that pairs well with demanding planars. Thanks! /Will

[@Ezees23]

@@WillieBloom I got rid of my OG A90 after comparing it to discrete Class A and Class AB amps - even the cheaper ones were better than the A90 when driving the Arya and Arya Stealth. I use a Gustard H20 right now, and the A90 doesn't compare, LOL......

[@JTB--]

Did an A/B with the A90D($600) and the SMSL SH-9 THX AAA($290). Kept the SH-9. Don't get the hype for the A90/A90D

[@foupax]

I will try to answer. I have both, the SH-9 for more than a year and the A90D for two weeks now. My DAC is a VMV D1se and my HPs are the Sundaras and Focal Celestee. At present time, I prefer the A90D for classical music and jazz, and the SH-9 for electronics and rock. But this may change over time, to be followed. I must point out that the Celestees don't match at all with the A90D.

[@JTB--]

@@foupax At the end of the day it's all subjective. And synergy is key with your headphones and the genre's of music you like. And I have to add if someone also needs a preamp than the A90D becomes way more attractive

[@tho4318]

Hmm about the headphone amplifier blowing up headphones, interestingly enough one of the ones I've seen people complain about is Burson Audio's Soloist 3xp. And that's a 1k ish headphone amp.

[@mfgillia7606]

Evidently a consistent problem with some Burson amps has been an issue with unusually high fluctuating DC offsets particularly when swapping opamps.

[@wazzupi-pubg]

@currawong will you have a video about yamahas New flagship ?

[@Currawong]

If they send me a pair.

[@wazzupi-pubg]

@@Currawong you auditioned it a bit right ?!? Does it lean towards final d8000pro or susvara in signature ? I already own the d8000pro limited edition

[@Currawong]

I don't remember to be honest, especially given I couldn't compare them side-by-side.

[@20puskinas1992]

Question for Currawong. there is lot of talk that big capacitor banks are neccesary for dynamics, transients and other stuff... tiny transformers used in switched mode power supplies recharge capacitors many times faster than big toroidals used in linear power supplies... Wire is much longer in toroidal and thus need much more capacitance... Why does linear supply is better? if both wont be running out of steam anyway. P.S i dont think that Schiit power supplies is anything amazing for example or have high cost. Even Niimbus US5 toroidals are cheap. Also Schiit asgard also blown headphones? Why you didnt mention this?

[@zzezzobike]

I just ignore Topping users, never knowing what real music is but only pick up sounds and pieces. I like your taste and knowledge Mr. Currawong. Ignore negative comments.

[@chrisharris1522]

If you ignore them, then how do you know what they know?

[@mikeg2491]

I somewhat get what those ASR guys are driving at but I’m sorry I just can’t dig these cheap Chinese crap with their plastic shells and clicky buttons with no character. The whole philosophy is wrong to begin with too, if you’re going for accuracy or “engineer’s intent” you’d be seeking out the same exact hardware an old 70s Rolling Stone was recorded on, which frankly would sound like crap compared to today’s technology. If musicians didn’t intend for us to have fun or experiment with our records you wouldn’t have guys like Jerry Garcia wiring up 600 speakers to 100 McIntosh amps to create a wall of sound just because he could. And they DEFINITELY would not want you smoking grass either because nothing distorts music more than being high as fuck!

[@brodyjorgensen2663]

I own a brand new A90D but I'm waiting on the D90se. If it doesn't work out ill figure out how to afford a better one. 😆

[@Nightjar726]

FINALLY. someone is trying to explain what linear power supplies do and how they make a difference in sound quality and sound sig. All these products were just giving a certain suite of measurements and basing sound quality on just those. Thank you so so much for this and I am looking for more info from this. I have extensively discussed this with passion for sound as well. We need to move forward now from those recent suite of measurements.

[@onepieceatatime]

You can measure a car's acceleration from say 0-60, and while one might clearly be faster than another, that and similar measurements tell you only so much about how the car will actually perform on a race track or the road. Let an experienced sports car driver compare them, and you'll have a real world answer. And there's so much more involved beyond standard measurements - things like the synergy between the tire compound, the road surface, the suspension, the temperature, the humidity, wind, etc. - that you'd have to "measure" all the way down to the molecular level in real time to really know what's going on. That, or just drive the car. Audio is similar. Measure what you can, then listen.

[@maniacaudiophile]

The part about how power supply is like class A, AB, D are so so wrong... Most of all the switching power supply have a transformer still, to drop the voltage as well as provide galvanic isolation. Only vary rarely do you have direct mains step down switching power supply. If those are called de-amplifier, then tube amps with output transformer... Which drops tubes' fairly high output voltage swings to something speakers can use. Are you going to call tube amps as tube de-amp instead? Also class A and AB amps don't compare that well to linear regulators, since amps and voltage regulators' job are just so different. Unless you are comparing the difference between series and parallel linear regulation, which does resemble the difference between Class A and Class AB, where one of them will actually run cooler than idle if there's a load on it.

[@Currawong]

Regarding my comments, which I said were not entirely accurate, I was, for example, referring to what is mentioned about Class D and SMPSs in Wikipedia: "The structure of a class-D power stage is somewhat comparable to that of a synchronously rectified buck converter (a type of non-isolated switched-mode power supply (SMPS)), but works backward. Whereas buck converters usually function as voltage regulators, delivering a constant DC voltage into a variable load, and can only source current (one-quadrant operation), a class-D amplifier delivers a constantly changing voltage into a fixed load, where current and voltage can independently change sign (four-quadrant operation). A switching amplifier must not be confused with linear amplifiers that use an SMPS as their source of DC power." Both use high-frequency switching for efficiency, and both require a noise/low-pass filtering to remove the switching noise.

[@supergwizzo]

Sinad is related to music ... more details n micro details more space between instruments and Blacker background and more dynamic range ! 😅😅😅 😊😊

[@Jellias11]

I bought the entire topping setup for my office. I use the a90d for headphones and extender so I can run my headphones and my Polk r200’s, Svs sub, all balanced. I use 2 la90 amps in monoblock. I also run the optical from my tv through the 90 dac. The entire set up runs great with clean sound. It allows for flexibility and ease of use for an entire av system at a reasonable cost. I do prefer my Schitt Jotunheim 2, Bifrost 2, for my high end headphones. The Schitt is more revealing and I enjoy the sound over the topping. However the topping serves its purpose but I wouldn’t recommend it for the best quality audiophile sound.

[@dangerzone007]

If a worse measuring amplifier sounds better they're obviously not measuring the right things.

[@kellustzall3057]

Wow damn, measurement chasers are so desperate now. They really want to believe that actual professional people are making huge ass fundamental mistakes that somehow average consumers like them are terribly aware of.

[@wazzupi-pubg]

@@kellustzall3057 it's called having a narrative get with the program.

[@spamcan9208]

Correct me if I'm wrong but are humans even capable of detecting the measurement difference between amps at the levels being discussed today? For instance a test tone is different than something like a single trumpet playing the exact same frequency. This "hobby" is very frustrating and annoying. It's barely even about the music sometimes, you'd think some people are jamming out to test tones all day.

[@zackw4941]

I haven't heard the new Discrete, but I own the original A90. I found it to be significantly more 'musical' than something like a THX-789, which I also owned before. It's not quite in the same league with something like my Audio-gd Master 19, but it's not far off either. Anyone looking for a simple, work horse solid state could do a lot worse. Especially considering the small size and reasonable cost. Pair this with an R2R DAC such as Denafrips Ares and you have quite a nice sound. Easily an end game system for the sane among us.

[@carlosoliveira-rc2xt]

@@siddharthjaiman4712 Nonsense!

[@MRFUTURETECHNOLOGYGAMING]

Topping p50 Linear power supply Works well with the topping D90

[@Currawong]

That wont work. The D90 doesn’t use a wall-wart.

[@Bladel1965]

Maybe time to brush up your knowledge on the subject of PSU's in audio. More and more high end audio manufacturers are changing to switching PSU's because they are just better suited for the job. Benchmark is an example and they have a nice blog on their website about this topic, but also companies like Mola Mola use switching power supplies in their high end devices. Why? They're less noisy, for example, because their high switching frequency is far outside the audible frequency spectrum and can easily be filtered out so it doesn't interfere with the audio signals. Linear PSU's are subject to hum from mains (50 or 60Hz and 100 or 120Hz when rectified), which is exactly in the audible spectrum. These things can easily be measured.

[@scubaman2546]

Great review. The A90D is better for users who are obsessed through customizable volume controls.

[@lwdp74]

Topping has a 5v linear power supply for some of their DACs. I found it improved the sound more than any reviewers claimed. Be interested to build similar power supplies for Topping’s PA5 and LA90 power amplifiers, though they sound pretty good with their switching ones.

[@jungtarcph]

love the discussion of connecting a linear psu via the underside!!!

[@lwdp74]

PS Cheaper DACs benefit more. I tried the power supply on a $20. dollar DAC and the improvement was amazing.

[@User_not_found_403]

Used to own one. Sounded clean but had a weird tinny feeling to it. Something unnatural that I had difficulty describing. Also I had issues with the volume control randomly jumping around and skipping levels.

[@VaporEG]

He just said it was fixed with a firmware update.

[@ranjanthomas5982]

Audiophiles are a bit snobbish aren't they? Thanks for showing us the cheap switching power supplies on the inside. When you review the $30,000 dCS Lina headphone amplification system don't forget to mention that it uses a 9$ Alps RK27 volume control. Easy to disparage the more budget oriented brands like Topping but don't forget to point out the faults of the ''high end'' brands as well. They cheap out on components all the time as well. You pay for the marketing and a fancy case.

[@Currawong]

I had a look at a pic of the dCS Lina's innards, which show 4 amplification channels, and only a 2-channel Alps pot. That means, more likely, that the pot is being used to control a digitally activated volume, since it has a motor allowing it to be remote-controlled.

[@Dave30867]

There is not much inside this unit compared to the price of it i do not see the value in it myself. But i will probably get one if the price comes down in time . 🤔

[@dalejail]

of the sa-1 and a90d which is more studio reference in sound?

[@xyanide1986]

The Rupert neve rnhp

[@alphaniner3770]

I had the SA-1 and the A90 (not D) - and I would say that the Topping is a lot more studio reference.

[@olivergoldvalente]

So is there a better $600 amp that uses a better power supply and has just as pleasing a sound? I might have missed it, but most of the comparisons seemed in the thousands of dollars or they were tube amps, which regardless of clarity/detail should provide a different sound than desired by the audience buying this topping. You said you did not want to review the amp when starting the video and I felt that all the way through haha. I was hoping to get some useful comparisons or price to performance explanations. You just seemed bothered by doing this review. I'd love some recommendations it's very clear you know your stuff.

[@Currawong]

Did you watch the entire review?

[@olivergoldvalente]

@@Currawong What??? Really???? I'm coming to you because I'm not understanding your video...yeah. I watched the whole thing.

[@olivergoldvalente]

@@Currawong I'm still confused. I watched the entire video.

[@Currawong]

I have trouble believing that, considering I compared it to multiple amps around the same price from the 19 minute mark onwards.

[@olivergoldvalente]

@@Currawong After a rewatch I can understand my confusion. Regarding the Singxer sa-1, most people don't want to modify their amps. That made it a bit of a dead comparison to me. Then the SGA1 made more sense, but at this price point people are usually buying 1 amp as their main, so buying something underpowered would scare many, myself included, away. Most damning was how the comparisons were undercut by your point about the amps being less detailed than your other more expensive equipment. You said even your tubes bringing out more detail. I don't think insulting your audience and calling them salty during your statement about measurements was a great play either. If you don't see the value in amps under $600 then you should make a video about that! Might be an interesting talk on price to performance. The comparisons were barely two minutes of your 20 minute video and I was left with no good answer and you picking on your audience for their shopping habits. Your earnest alternative seemed to just spend more money.

[@peteranderson6932]

Way more important than cheap power supplies that may not last 10 years, as you state in the review, is the fact who will service these amplifiers inside the country where you live. Zero service is far more important than zero distortion static metrics. Nothing is more unsustainable than throw away devices because of zero consideration to easy service after the sale. Society should wake up to the costs of fad devices and the temporary philosophy that is the basis of such devices.

[@dougleydorite]

Electrical wizard!

[@enhncr]

If someone says that the amplifier “sounds” I say: go back to primary school. This is madness. Just do an abx tests and you’ll see there is no difference in sound between dacs and amps.

[@Currawong]

An engineer can change: The crosstalk vs. frequency pattern. Often done in amplifiers to bring the effect of greater soundstage. Change the amount of 2nd and 3rd harmonic distortion. Depending on amount, it's very audible. The amount of noise floor modulation, which masks detail. The power supply, which can improve bass distortion. This is measurable into very audible levels. The digital filter in DACs. This causes phase shifts which, with speakers and some headphones, with many recordings results in audible changes in the perception of the depth of soundstage.

[@DJMikeron]

Topping DACs are well fulled with technology like the new DX9 which was the biggest disappointment ever sound wise. Beautiful DAC but for 1300 euros a rip off. I’ve heard better DACs for 300 Euros

[@arrowzen7433]

So you can not upgrade the power supply on the this?…why the hell not a proper linear PS when you go for a discrete output stage?…at least make the option for an external…