Aurender makes a fairly large number of music servers, which on initial examination looks complex, but in reality is quite simple, and quite logical in its pricing structure. Basically you just need to break it down to the Aurender N100 series vs the W20/N10
Aurender N100 Series
This is the series that is perfect for those of you with USB DACs who have medium/high performance needs. All of these handily outperform an SSD Mac Mini, but not crazy high end systems. If you have an Ayre QB9 or CODEX, Mac D150 or Preamp / Integrated / Receiver that has a quality asynchronous USB input, you should probably buy a '100' series Aurender.
The Aurender N100C is an N100H with an added digital Coax output.
The Two other Aurenders - W20SE & N10
Which leads us to the two remaining Aurender Music Servers: the W20SE and its little brother the N10.
If your DAC has best-performance Optical or (more realistically) AES/EBU input, you need a W20 or N10 because they are the only two Aurenders with Optical/AES in addition to USB. The N10/W20 are more future proof than the N100 series because they have USB, COAX, Optical, and AES/EBU outputs rather than the either/or nature of the N100H (USB out only) or N100C (Coax out only).
The N10 is a sonic performance improvement over the 100 series.
The Aurender W20SE
The W20SE is The Statement. It has massive internal metalwork/isolation with separately isolated motherboard/audio boards, battery power for the audio board, precision oscillator for low jitter, higher specification power supplies,all SSD storage, and is truly intended for those $100K+ system open class high performance systems.
Functionally the W20SE and N10 both have Optical/BNC/COAX/AES and USB. Above the N10, the W20 has three unique but important functional features:
A word clock BNC input which allows you to have an external clock time the outgoing bits (same clock will feed your DAC),
Dual-wire AES/EBU. You need this to connect some DACs to get their full performance and feature set (see below). This basically separates out the data over two channels to improve bandwidth and data flow.
PCM upsampling. This provides a huge improvement from sources such as Tidal and Qobuz.
The Aurender N10
Stepping down to the N10. It's an interesting combination in that it is fairly expensive at $7999, but if you have a high end Coax or single-wire AES/EBU Dac, it is the least expensive Aurender that supports this. It's a pretty big jump from the 100 series, but it will sound better and gives you multiple outputs.
What it has performance-wise is a higher grade oscillator for low jitter, phase lock loop, larger SSD, and generally a higher level of build quality and isolation than the 100 series. So it sounds better.
Functionally, it has Optical, Coax, BNC, AES/EBU and USB, so if you are a DAC-swapper or want to feed other components in your system it fits the bill. The big functional need is if you have a DAC with Coax or AES/EBU input (optical is lower performing). A less important but very convenient functional benefit is the ability to on-the-fly convert DSD files to PCM. This is terrific if you have something like a Berkeley Alpha or Reference DAC which only supports PCM data (no DSD). True, you can convert DSD to PCM using your computer and software, but this makes the experience seamless.
The Aurender W20 vs Aurender N10
I had the opportunity at CES to meet with my longtime friend John-Paul Lizars and I asked him if I could listen to the N10 vs the W20 on their reference system which featured a dCS Vivaldi DAC and a dCS Vivaldi Master Clock. This was a perfect and unique opportunity to hear the W20 shine in it's intended dual-wire, clocked configuration.
I first listened to the N10 and it was superb. It was easily some of the best digital sound I heard at CES. Effortless really and an excellent choice for a high end non-clock input DAC.
Now onto the W20....
John-Paul next disconnected the N10 and connected up the W20.
John-Paul connected two clock wires from the DCS Vivaldi Master Clock. One feeding the dCS Vivaldi DAC, one feeding Aurender W20. This synchronized them, and gave the W20 the benefit of an even higher end external clock. Next he connected the dual-wire AES/EBU. Dual-wire AES/EBU allows the Aurender W20/Vivaldi DAC to split the transmission of data over two, instead of one, data lines and improving data bandwidth, reducing digital errors, improving timing, resulting in better quality. Functionally, a dCS Vivaldi can play up to 24/192 and DoP over one AES/EBU. Going to 2-Wire AES/EBU increases the Vivaldi to 384kS/s & DoP and dCS encrypted native DSD. The big deal here is the native DSD.
John-Paul played the same tracks for me, and we listened and talked for a while. Sonically it was a huge improvement. The dual-wire AES/EBU, clock-synced Aurender W20/Vivaldi had a significantly larger soundstage, greater analog ease, and the refinement and stillness that was quite unique to the combination. I'd heard several Vivaldis at the show, and I can tell you this was absolutely magnificent amongst them. I have a pretty good feel for what improving to a lower-jitter clock sounds like, and the N10 vs W20 exemplified that perfectly. For what that system cost it was an easily recommendable upgrade. I personally would not buy a 2-wire AES/EBU, clock input super-DAC without budgeting for an Aurender W20.