Topping A30 Pro Sound Breakdown
Frequency Response –
Testing Methodology: RMAA via Startech External Sound Card
The A30 Pro offers a linear frequency response through the audible spectrum, an ideal result. This suggests that it adds no intentional coloration to the sound in line with Topping’s marketing material. Due to the quality of my sound card, I am unable to reliably test other measures such as distortion and crosstalk so they will be used as a personal reference only. Qualities here can impact the sound in subjective listening.
Output Impedance & Hiss –
The A30 Pro offers a huge spec bump relative the lower-end NFCA-based amplifiers from Topping but retains the same 0.1-ohm output impedance while promising a low noise floor. And this is exactly what the buyer receives. As usual, I confirmed this in subjective testing using the Campfire Audio Ara (8.5 Ohms, 94dB). This earphone has a mechanical crossover and a very low impedance, making it able to discern between even 1 and sub 1-ohm sources. It is also very sensitive to source noise. The A30 Pro here impressed me greatly here, in fact, more so than past Topping devices.
It too was dead silent on low and medium gain, picking up just a little EMI interference from my PC on high gain. This means even low volume listeners can enjoy a perfectly black noise floor when listening to sensitive IEMs and the effective dynamic range is increased. The Ara also sounded slightly more balanced from the A30 Pro, with a more even and textured treble, as opposed to my THX789 with its 1-ohm output impedance. This effectively demonstrates its incredibly low output impedance. It is impressive that Topping have been able to achieve this as the A30 Pro has more power than past devices and with zero noise or hiss. This makes the A30 Pro a sensational choice for sensitive multi-driver IEMs.
Driving Power –
The A30 Pro has huge driving power on paper, in fact, more than the A90 through single-ended. Indeed, in listening I never felt it was lacking and this makes it a great choice for those more invested in single-ended equipment. Max volume is huge, aided by the large gain steps too. It holds up well at high volumes, sounding less strained than most amplifiers I’ve tested. The A30 Pro scores a firm “very good” on dynamics on just about every pairing I threw at it, whether that be the Hifiman Sundara, the Final Audio D8000 Pro or anything in-between. I cannot say the same for every amplifier that comes through for review. Compared to the A50s and L30 too, you do notice a step up in overall dynamics and power.
Note attack is concise and there’s a more physical pressurization at the very bottom than the aforementioned models. That said, I do feel like the physical dimensions of the amp and the integrated power supply are limiting it to a degree compared to the best models in-class. This was most notable on explosive sub-bass heavy passages with lots of kick drum – think midway through “Lateralus” by TOOL around 4:30. Here, I found the A30 Pro did lose some tactility and didn’t offer quite the sub-bass responsiveness I wanted. The larger THX789 kept pace noticeably better despite having less peak output power. Complex passages were flattered with a deeper, more weighted slam and greater pressure, providing a more visceral listen even if in less busy passages, both perform similarly.
Testing Methodology: SPL volume matched AB with D8000 Pro connected to in-line splitter between THX 789 and A30 Pro both connected to SMSL SU-9.
As one would expect, the A30 Pro exemplifies a clean, linear sound. As always, with source reviews, the extent of the change between linear sources when impedance is disregarded is far less than you would encounter between headphone to headphone. However, subtle colouration is evident on each model that can enhance your particular setup. As before, the THX789 remains my personal benchmark as I purchased it myself and find it to offer the most well-rounded experience despite long since relinquishing its crown in the measurement department.
The A30 Pro offers an immaculately clean and linear sound that is incredibly even-handed throughout. As I spent more time with it, I found myself enjoying it more than most that pursue a similar style of sound as it lacked the dryer character many similar amps possess. Where the A30 Pro differentiates itself is with its note weight that is neither heavy nor light, but just about neutral. This means it sounds a little more separated than the more heavy-handed THX789 but also not quite as dainty as the A50s and SH-9. It means the amplifier is able to retrieve huge amounts of texture whilst upholding a highly accurate timbre and transparent tone.
Don’t dismiss its small size and integrated power supply, I was very impressed by the low-end control and dynamics on the A30 Pro. It kept up admirably with the THX789 here and did so with a more accurate note weight and size. The Drop amplifier has a noticeably bolder note presentation, often sacrificing separation and articulation for greater slam. While the 789 sounds more robust as a result, the A30 Pro is simply more accurate and no less dynamic or extended. It has a more linear sound, working to maximise detail retrieval. Alongside a slightly keener note attack, the A30 Pro is an altogether more articulate source that retrieves more fine texture in the mid-bass and provides generally higher note definition. As above, the THX does have a leg up on complex passages where the A30 Pro runs out of steam. But this is only in very specific instances so the extent this impacts the listening experience will rely on mostly your genre preferences.
The midrange too upholds a similar quality, being highly linear and showcasing minimal colouration. The A30 Pro sounds even and has an almost perfect coherence that can only be achieved with ultimate balance. In so doing, it sacrifices zero separation or definition. The THX789 once again sounds a little fuller here, it has a bolder note structure and sounds a bit more powerful. It also has slightly higher contrast with a sharper articulation that lends the impression of greater definition. However, boot up a song with many layers of vocal harmonisation such as Billie Eillish’s “my future” and the A30 Pro does sound cleaner and more refined, with greater delineation between each element in the midrange. While both are tonally transparent, the Topping has a more neutral note size and slightly higher note definition. The differences aren’t stark but appreciable, and the two qualities combined allow the A30 Pro to separate better and discern more texture than the Drop amplifier within the midrange.
Up top, the Topping continues this impression of refinement. It has a linear and well-resolved foreground paired with a darker albeit immaculately clean background, especially paired with its low noise floor. The THX789 does have a slightly sharper note attack in the foreground, giving the leading edge of notes a bit more zing and bite. However, it also rings a little more, which I do not consider greater detail retrieval. The A30 Pro sounds a bit more controlled here. Its transient response is a bit cleaner; it doesn’t have the same sharpness in its note attack but separates a little better, retrieving a hint more fine detail. Above, the THX789 provides a little more headroom and air while the A30 Pro provides a darker background forming a more stable presentation. The A30 Pro has less shimmer, decaying faster, trading energy for superb cleanliness. Albeit, this does come at the cost of top-octave sparkle which is a bit more pronounced on the THX789.
And with regards to soundstage performance, it’s a mixed bag to my ears. You get a good ability to expand in both width and depth. The THX789 is a little wider but tends to position wider too, emphasizing its sense of space more. While the A30 Pro is capable of similar positioning on certain tracks, it generally sounds a bit more intimate. On the contrary, it does have a great depth and projects well on most tracks, better than the THX789. The A30 Pro benefits from slightly sharper imaging overall with more pinpoint precise localisation. It is a bit faster than the THX789 and more holographic when called for. The THX789 meanwhile appears to layer a bit better, mostly across the lateral plane while the A30 Pro has a sharper centre image and sense of direction.