“The best amp on earth” is $600: Zeos Reviews the TOPPING A90D

Note: This article is based upon the video "Where do we go from here? || The Topping A90 Discrete ..." made by Z Reviews on his YouTube channel and is printed here in partnership with Z Reviews. The review was originally posted on August 22nd, 2022. Edits have been made for clarity and length. The TOPPING A90D Amplifier is for sale on Apos Audio.


Usually when I start getting ready for a review, I pull out a couple of headphones and I listen for an hour or two–not five hours.

Before we get into that, let’s have a real quick history lesson. The THX AAA-789 changed the world. That was the most linear amplifier ever, and it stayed that way for approximately 12 to 14 months. And the reason it stayed that way for so long is because the TOPPING A90 hadn’t come out yet. People were asking, “Is the A90 the best amp ever?” And the answer was probably, at the time, pretty much yeah.

Let me tell you about the A90 Discrete though. Is the A90 Discrete the best amplifier ever? The answer to that question is **** yes. Is this the best amp ever made? Yes. That’s it. End of review. Thank you. Don’t forget to join my Patreon.

There’s only one other amplifier that comes close, which is a $5,000 Fidelice DAC/Amp combo. The A90D, on the other hand, is $600. It is $600, and it is perhaps the best-sounding amplifier there’s ever been.

I’m sitting here after five hours of listening to it. My ass hurts.

The Sound

How do I describe the sound? Let me first describe the sound of the $5,000 Fidelis, as a comparison. So the Fidelice… imagine that you get into the back of a Maybach. It’s a big heavy car. And you know it’s not going to win a drag race against a Ferrari, but it doesn’t matter because the cushions are so thick and made of some sort of special dead cow, and you just sit there, and you know you’re better than everyone else. When I plugged into the Fidelice, everything sounded opulent. It made you realize that everything I’d been listening to is garbage, and when I closed my eyes I could picture girls fanning me with big leaves, and someone’s rubbing my back…that’s what the Fidelice did.

The A90D is just like that, but it has more power.

I don’t think anyone’s gonna say anything negative about the actual shape of the A90D sound. It doesn’t remove any highs. It doesn’t quell the lows. The bass isn’t weak. I want to say it’s textbook. But I’m pretty sure the textbook hasn’t been written yet. If it has, only TOPPING has a copy of it.


The A90 was super linear without being dry. The 789 was a dry amp. You plugged into it, and it had nothing, but that’s what you wanted. You wanted nothing. You wanted clean and pure, but like sterile pure in the vacuum of space pure. The A90 gave you a little bit of atmosphere with the purity. And then Singxer came in and put its feet up on the table and drank a beer with you. And then the Burson did very similar things to the Singxer, but it was op-amp driven, which gave you this flavor. And then you have the iFi Zen Can here, and I love that damn thing. All of those amplifiers have little bits of nuance and detail and things I like about them. All of those things can be found in this one A90D. It doesn’t have a bass boost like the iFi, and it’s not class-A like the Singxer, but the warmth and creaminess and clarity is all there. It has this weird hodgepodge of layering, like a seven-inch high sandwich that does everything you’ve ever wanted.


This amp is a huge leap.

I believe this is the best-sounding headphone amp that exists on earth. Certainly for the price. Without a doubt for the price. If we’re talking about a price-to-performance, the king is here.

Everything is staged perfectly. Everything is placed perfectly. If you plugged in the shittiest headphones on earth into this, they would sound remarkably better. That’s my theory. This could almost fix bad headphones.