TOPPING A70 Pro Amp: Closer Examination

As with any matching amplifier meant to be stacked with the simultaneously-released DAC, the TOPPING A70 Pro follows the exact same design language down to the use of the same external CNC-machined aluminium alloy chassis at 222 x 176 x 48 mm, albeit slightly heavier at 1.27 kg, and comes in the same black or silver color options to better pair with the D70 Pro SABRE. The funny thing is, as evident from the previous page, the actual PCB inside doesn't extend the entire width of the unit and it's the same here too. Some of the empty space is used by the electronics for the display and volume wheel but I am not sure these needed to take the footprint they do. The good news is the identical shells translate to the inclusion of a dedicated 2" LCD display here too. Of course we also get the Hi-Res Audio badge visible here and then most of the same follows from the previous page including the company logo and product name, a set of three capacitive buttons to the right of the display and an IR receiver port in the middle, and then we get the three headphone outputs including full-size 4-pin balanced XLR, 4.4 mm balanced TRRS, and 6.35 mm (1/4") single-ended TRS connections. There is a matching volume knob/button at the end which makes more sense here on the amplifier.


This is a solid state amplifier and won't get hot like many tube amplifiers will. As such, the same lack of vents from the D70 Pro chassis continuing here wasn't unexpected to see. Things get busy on the back though, which makes sense given the TOPPING A70 Pro is not a beginner's amplifier but it's funny that here TOPPING has marked the inputs and outputs similar to how I would have liked the D70 Pro to also be marked. On the left is an accessory port allowing the A70 Pro to be connected to TOPPING's Ext90 input extender which adds three XLR stereo inputs and an RCA stereo input in addition to the one of each input type you already get with the A70 Pro. This means that you could have a plethora of different inputs feeding the A70 Pro amplifier, although practically most people will be happy with the one set each available here since you can use both simultaneously anyway. The XLR inputs are actually combo ports offering both 3-pin XLR and 1/4" TRS balanced input from a compatible source, including the D70 Pro SABRE as we saw on the previous page. You can also use the A70 Pro as a preamp and thus we get dual 3-pin XLR and a set of RCA outputs too. We see the same 12 V trigger as on the D70 Pro SABRE DAC and there is also a Type-C port for any firmware updates for the A70 Pro itself, which is nice to see for those looking for a longer-term solution. A handy toggle helps eliminate any ground loop noise—set it to GND in normal use and Lift if you experience said noise. Rounding off the back panel is another of the same 3-prong power cable inputs and the associated on/off switch itself.


The sticker on the bottom confirms the amplifier is rated for much more power in compared to the DAC, which makes sense and will continue to do so once you see how much power this thing can put out even if it does not take in anywhere near as much as the theoretical maximum. The same set of four feet are present here too, including with the gold trim around them. Disassembly of the A70 Pro amp is achieved in a similar manner as the D70 Pro SABRE DAC before and was done after all testing was finished until the same end point. Here too we see a very similar low noise integrated power supply in use and then the relevant section is for the amplification stage itself where TOPPING uses a new architecture it calls the "T'ang-ku-la" module which uses a 3-stage feedback circuit and promises dynamic range on a scale that is already well past the point of human hearing but also reduces heat generation which in turn improves component life and reduces noise. The amp also uses relays and resistor networks to allow R-2R volume control for increased precision and further reduced channel imbalance from the already impressive user experience in previous TOPPING amps. We still see plenty of heatsinks and large capacitors inside as usual and the A70 Pro amplifier has also been independently tested to please those who care purely about SINAD and similar such metrics.