Closer Examination

I knew going in that the Gustard A26 is a premium product that has quite a few tricks up its sleeve but even so I was not ready for the size and heft of this thing. It reminds me of larger integrated amps and 2-channel DACs you would require a dedicated audio rack for and it certainly would fit in nicely underneath your TV cabinet as part of a living room home theater setup. The Gustard A26 is 33 cm long, 26 cm wide, and 6.5 cm tall while coming in black or silver color options. Note that the silver here would be the top, front, and bottom panel with the sides still being black. Both versions look extremely classy if I say so myself, and I have the all-black version here which puts every other DAC reviewed to shame in terms of fit and finish. The thick sandblasted aluminium alloy case is very well executed without being a fingerprint or dust magnet either. There are softer corners in the front too, where we see the Gustard logo laser etched in white on this model in the top left corner and a small A26 on the bottom right corner. The rest of the front is occupied by a touch panel OLED screen with a glass screen protector on top. There are actual buttons here too but they are invisible until the display is turned on. The sides have a patterned aluminium section that might be a heatsink too, although the lack of any side or top vents suggest the A26 isn't expected to be a warm-running product.


The back is where all the action really is and also where we see Gustard has justified the size of the A26 with a vast plethora of connectors provided. Going from left to right, we have analog line out via single-ended RCA and balanced dual 3-pin XLR allowing you to connect the A26 to any device accepting analog audio inputs, such as a headphone amplifier or an integrated amp for speakers. Then we get to all the inputs, but don't be misled by that USB Type-C all the way at the top which is only to help update the firmware of the device and nothing else. I do wish Gustard had adopted Type-C for data connectivity too given the world is rapidly moving towards it and away from USB Type-B, which we do find here and what the provided cable is used with. Between the two is an RJ45 LAN input for internet connection to the streamer part of the A26, and I believe it maxes out at 100 Mbps which might seem low but is already overkill for anything the A26 can do. Gustard also provides I2S, coaxial, optical, and AES inputs here for use with more specific/prosumer gear. We also get a clock input for use with external clocks should you choose to partake; Gustard boasts about the internal clock while also aiming to market its own line of external clocks to get more sales of course. Given the external clock is fixed at 10 MHz and not a true multiple of standard 44.1/48 kHz playback rates, I am not convinced you will gain anything good doing so here. The right side caters to the power section of the A26 wherein you can select the operating voltage, thus making this easily usable if you take it with you around the world, as well as the expected power input connector itself. An easily accessible fuse and a dedicated on/off switch round off this section.


It's only on the underside that Gustard has decided to add some vent holes for any possible passive cooling. There isn't much else to see here outside of four large machined aluminium feet at the corners that have a knurled finish to help install/remove them should you wish to add in your own set of replacement feet and these stock feet come with a large rubber pad to add friction against the resting surface as well as prevent any scratches to the metal chassis itself.


I am deliberately going to avoid explaining how to disassemble the Gustard A26 because it isn't trivial to do so without also potentially getting a few other components loose/damaged along the way. Of course doing so also voids warranty and there isn't a practical reason for you to do so anyway—I did it purely out of academic interest to examine the build quality and design/components used here. The thick aluminium top panel is the first to come off and I decided to also remove the side and front panels at the same time by loosening some specific screws as well as the internal connector going to the screen that is placed on the front panel. There is a daughter PCB here helping power and control the touch screen and buttons.


This now provides a closer look at the bottom panel that in turn houses everything else. We see that Gustard has decided to split everything into three sections effectively, with more thick aluminium panels between them. I understand the Gustard R26 follows a similar design, perhaps the X26 Pro also. The left section caters to the power delivery into the A26, the middle section handles the digital inputs, and the right section is responsible for the analog outputs.


There are two 50 W toroidal transformers helping out with the power delivery stage on the A26. These come isolated from the chassis and are seemingly "audio grade." These also shift the center of gravity towards the first section and we see cables going over to the middle section. It looks like one transformer powers the digital inputs and another the analog outputs, thus reducing the power-based noise floor if you so care. The middle section uses high-grade Nichicon Gold capacitors as part of the power filtering stage responsible for the Gustard K2 internal femto-second clock which is a custom design again built around ultra-low noise and jitter reduction. We see voltage regulation on either end of the clock as well as an unlabeled Gustard controller—perhaps for the streamer/encoder functionality available here. There are also more familiar parts here including the XMOS XU216 USB bridge as well as an STC Micro STC15F2K60S2 microcontroller. Of interest was also the micro-SD slot that has a card installed for the A26 firmware and the relatively thick internal cabling throughout.


The analog output section is where we will see two of Asahi Kasei Microdevices' new flagship DAC—the AKM4499EXEQ, one of which was used in the TOPPING E70 Velvet and I quite liked it there. This is a dual-channel (stereo) DAC and thus, for a fully balanced architecture as used in the Gustard A26, you will need a minimum of two AKM4499EX units as seen here. This is also why some flagship DACs and DAPs go with four of these chips—quite overkill! The DACs are associated with an external AKM AK4191EQ digital data converter (modulator) that is responsible for the so-called "velvet sound" tech from AKM as well as the various digital filters on offer in the A26. There are plenty of other discrete components including diodes, more of those Nichicon Gold capacitors, op-amps and various transistors too before you get to the output connectors themselves. It's a nice design that no doubt helps elevate the A26 up a tier or two from the likes of the TOPPING and S.M.S.L DACs, and also helps achieve the various numbers listed in the specifications sheet. Note that different companies measure differently and we are well past the point of solid-state DACs having any practical noise perceivable to the human ear. As such, I am more interested to see if DACs can actually justify their cost in terms of the build, feature set, I/O, and whether there is any difference in the sound output more so than how they measure.