===>2150mW x 2 @16Ω THD+N<0.1% 1400mW x 2 @32Ω THD+N<0.1% 190mW x 2 @300Ω THD+N<0.1% 100mW x 2 @600Ω THD+N<0.1%
===>2150mW x 2 @16Ω THD+N<0.1% 1400mW x 2 @32Ω THD+N<0.1% 190mW x 2 @300Ω THD+N<0.1% 100mW x 2 @600Ω THD+N<0.1%
===>3500mW x 2 @32Ω THD+N<0.1% 2700mW x 2 @64Ω THD+N<0.1% 760mW x 2 @300Ω THD+N<0.1% 395mW x 2 @600Ω THD+N<0.1%
===>3500mW x 2 @32Ω THD+N<0.1% 2700mW x 2 @64Ω THD+N<0.1% 760mW x 2 @300Ω THD+N<0.1% 395mW x 2 @600Ω THD+N<0.1%
===> Rca and TRS (balanced) inputs
Total Score
Introduction
I’m here with a review of Topping A50iii, the last of the A series, priced at $199. The Topping A50iii is an extremely powerful amplifier. Combined with the Topping D50iii, the A50iii makes a great set and let’s see how good it is on its own.
I bought the product myself with the intention of writing an independent review. I spent about 150 hours with the Topping A50iii before writing my review.
Design & Build
The Topping A50iii has the same design line as the D50iii and is actually the same size. It looks less complicated, with 3 gain stages and a volume pot controlling the 6.35mm and 4.4mm outputs. On the back of the A50iii there are rca (single ended) and trs (balanced) inputs. There’s a button that allows you to switch between these inputs, and it’s clear even here that signal cleanliness is prioritized. This is exactly what comes out of the Topping A50iii box:
- -15V DC power adapter with European and US plug converters
- -6.35mm to 3.5mm adapter
- -Product information card
Topping A50iii comes with an adapter with interchangeable tips, compatible with different countries. I appreciated this a lot because they used a clever and simple mechanism instead of just putting a simple converter.
Specs & Technology
Like the D50iii, the Topping A50iii uses current components, but unlike the D50iii, the A50iii uses more components from the previous generation. The Topping A50iii has a very low total harmonic distortion and is also compatible with sensitive headphones. It does perhaps the most basic thing you would expect from an amplifier at its best, you get a linear gain response when you turn up the volume. I will give you a complete output informaiton chart instead of getting into technical details in this section:
| Parameter | SE IN/SE OUT | BAL IN/SE OUT | SE IN/BAL OUT | BAL IN/BAL OUT |
|---|---|---|---|---|
| THD+N @1kHz A-wt | <0.00006% @500mW (32Ω) <0.00006% @80mW (300Ω) | <0.00007% @500mW (32Ω) <0.00006% @80mW (300Ω) | <0.00007% @2000mW (32Ω) <0.00006% @320mW (300Ω) | <0.00012% @2000mW (32Ω) <0.00008% @320mW (300Ω) |
| THD @20-20kHz 90kBW | <0.0002% @500mW (32Ω) <0.0001% @80mW (300Ω) | <0.00005% @500mW (32Ω) <0.00003% @80mW (300Ω) | <0.0002% @2000mW (32Ω) <0.0001% @320mW (300Ω) | <0.0002% @2000mW (32Ω) <0.0001% @320mW (300Ω) |
| SNR @MAX OUT 1kHz A-wt | 141dB | 136dB | 144dB | 137dB |
| Dynamic Range @1kHz A-wt | 141dB | 136dB | 144dB | 137dB |
| Frequency Response | 20Hz-40kHz (±0.05dB) 10Hz-100kHz (±0.1dB) | 20Hz-40kHz (±0.1dB) 10Hz-100kHz (±0.5dB) | 20Hz-40kHz (±0.05dB) 10Hz-100kHz (±0.1dB) | 20Hz-40kHz (±0.05dB) 10Hz-100kHz (±0.1dB) |
| Output Level | 21Vpp @G=L 21Vpp @G=M 21Vpp @G=H | 21Vpp @G=L 21Vpp @G=M 21Vpp @G=H | 18Vpp @G=L 42Vpp @G=M 42Vpp @G=H | 18Vpp @G=L 42Vpp @G=M 42Vpp @G=H |
| AP measured noise level @A-wt | <0.7uVrms @G=L <0.7uVrms @G=M <1.2uVrms @G=H | <0.7uVrms @G=L <0.7uVrms @G=M <1.1uVrms @G=H | <0.9uVrms @G=L <0.9uVrms @G=M <2.1uVrms @G=H | <0.9uVrms @G=L <0.9uVrms @G=M <2.1uVrms @G=H |
| Actual noise level @A-wt | <0.3uVrms @G=L <0.3uVrms @G=M <1.0uVrms @G=H | <0.3uVrms @G=L <0.3uVrms @G=M <1.0uVrms @G=H | <0.7uVrms @G=L <0.7uVrms @G=M <2.0uVrms @G=H | <0.7uVrms @G=L <0.7uVrms @G=M <2.0uVrms @G=H |
| Input Sensitivity | 13Vrms @G=L 8.0Vrms @G=M 1.9Vrms @G=H | 9.2Vrms @G=L 8.0Vrms @G=M 1.9Vrms @G=H | 13Vrms @G=L 7.8Vrms @G=M 1.9Vrms @G=H | 9.2Vrms @G=L 7.8Vrms @G=M 1.9Vrms @G=H |
| Gain | -12.0dB @G=L 0dB @G=M 11.9dB @G=H | -12.0dB @G=L 0dB @G=M 11.7dB @G=H | -6.0dB @G=L 6.0dB @G=M 17.9dB @G=H | -6.0dB @G=L 6.0dB @G=M 17.7dB @G=H |
| Output Impedance | < 0.1Ω | < 0.1Ω | < 0.2Ω | < 0.2Ω |
| Input Impedance | 10.0kΩ @G=L 2.5kΩ @G=M 2.5kΩ @G=H | 2.0kΩ @G=L 2.0kΩ @G=M 2.0kΩ @G=H | 10.0kΩ @G=L 2.5kΩ @G=M 2.5kΩ @G=H | 2.0kΩ @G=L 2.0kΩ @G=M 2.0kΩ @G=H |
| Output Power | 2150mW x 2 @16Ω THD+N<0.1% 1400mW x 2 @32Ω THD+N<0.1% 190mW x 2 @300Ω THD+N<0.1% 100mW x 2 @600Ω THD+N<0.1% | 2150mW x 2 @16Ω THD+N<0.1% 1400mW x 2 @32Ω THD+N<0.1% 190mW x 2 @300Ω THD+N<0.1% 100mW x 2 @600Ω THD+N<0.1% | 3500mW x 2 @32Ω THD+N<0.1% 2700mW x 2 @64Ω THD+N<0.1% 760mW x 2 @300Ω THD+N<0.1% 395mW x 2 @600Ω THD+N<0.1% | 3500mW x 2 @32Ω THD+N<0.1% 2700mW x 2 @64Ω THD+N<0.1% 760mW x 2 @300Ω THD+N<0.1% 395mW x 2 @600Ω THD+N<0.1% |
| Load Impedance | >8Ω | >8Ω | >8Ω | >8Ω |
I would like to consider the Topping A50iii as a pre amp, but the A50iii is just a headphone amp. It doesn’t have a pre feature, which the Topping D50iii has. Although these two together make a complete set, I think such an amp should have a pre for stereo.
Sound
The Topping A50iii is a 90% neutral-sounding headphone amplifier that has almost no effect on the sound. Nevertheless, it adds a slight coloration to the sound with a micro warmth in the mid-range. When it comes to technical aspects and subtle nuances, the A50iii does a great job. It produces very clear and clean sound with very low distortion. Topping A50iii creates a transparent frequency response that adds texture without dampening the lower frequencies. It maintains the same transparency with very little coloration in the midrange and is very detailed in this area. In the treble range, there is a micro-coloring as in the mids, but it is a tiny brightness that has an analytical effect on the sound. In this area the Topping A50iii is both airy and has a natural extension.
The sound is generally well separated and well layered. It keeps dynamism and naturalness with very little maneuvers, staying true to the neutral axis.
Topping A50iii + D50iii With Hifiman Arya Stealth
In this part, I have analyzed the A50iii’s capabilities in the stack with the Hifiman Arya Stealth. Note that the Topping D50iii is used as a base here.
The Hifiman Arya Stealth with the Topping A50iii and D50iii pair sounds very analytical and wide, with a natural and slight midcentric presentation. A fully recessed sound and great imaging, yes this is a true planar performance. I have a hard time with this pairing in acoustic genres, but it’s very enjoyable in metal genres. When I turn on Far from Any Road by The Handsome Family, the song from that great show, I hear the vocals and the guitar very close together. I think this has something to do with the pairing. On the other hand, with this setup, Ne Obliviscaris – Forget Not wipes the rust off my ears. By the way, surprisingly listening to hiphop with this pairing is very enjoyable. With this setup you get a very flat sound, which lacks the necessary color in some genres, but the sound is still great.
Topping A50iii + Astell Kern SE300 (Line Out) With Hifiman Arya Stealth
Yeah, yeah, yeah, I know. It’s a bit weird, it’s not the first thing that comes to mind. But I couldn’t not write about it when it sounded so good, right?
That’s it! The Topping A50iii produces extraordinary power without touching the great tone of the SE300. When I take line out from the Astell Kern SE300, whether in OS or NOS mode, the sound I get is fantastic. I plug the line out from the SE300’s 4.4mm port into the balanced inputs of the A50iii (this requires a 4.4mm to 2×6.3mm cable) and use the A50iii in H gain mode with the volume pot at about 55%, listening through the 6.3mm output with the stock cable. This laborious pairing produces a great result. Layering, separation, positioning and overall imaging are at full potential. Resolution is very good, detail reproduction is top notch. The timbre is very realistic. The number one factor in achieving this sound is the Topping A50iii’s ability to deliver very high power with great signal quality and support the technique of the sound.
A Simple Advice For Use Case
First of all, of course, I recommend using the Topping A50iii in combination with the D50iii, which will give you a well-technically sound and neutral tonality. It will be a very refreshing stack, especially for closed back dynamic driver over ear headphones.
Let’s say you only listen to headphones, no speakers.
On the other hand, let’s say you already have only the Topping A50iii. It might make sense to use a dongle like iBasso dc07pro for the Dac. I know you will need to buy a special connector cable (4.4mm to 2xrca / 2×6.3mm). But on the other hand, with only two devices you will have both portable and desktop amplifier needs covered. The only thing missing here is a stereo dac. So this is only for those who listen to music through headphones. Also, the dongle you choose should have low THD+N numbers and as much as possible zero background noise so that the signal is clean. DC07pro is a good alternative.
Last Words
The Topping A50iii is an incredibly powerful headphone amp that produces a very clear and textured, well- separated and neutral sound with a quiet background. Honestly, I can’t see any downside to the A50iii other than the lack of a pre. I think the A50iii has advantages in terms of both sound and usability. Not only is it perfectly compatible with the D50iii, but it also worked very well with the devices I used as dacs by taking line outs. Considering that the price is also reasonable, it will do the job even on its own. Someone who only listens to iem can buy this device and start listening over-ear with their existing setup.
