 A frequently returning question is whether a network player sounds better using a network cable or Wi-Fi. An easy question, so let's see if there is an easy answer. Let's start by summing up some advantages and disadvantages of Wi-Fi. Of course, Wi-Fi is more convenient than installing network cabling to the position of your stereo. But cable as a medium is private to you and your family, while Wi-Fi as a medium is available to anyone. That doesn't mean they can access your network but it does mean they can use part of the available bandwidth. And if more people start using the same bandwidth, that's going to be a shortage. That's when problems occur for streaming. Although loading a big spreadsheet will take somewhat longer, the spreadsheet will arrive without errors. But with music you need those samples coming in at very regular intervals. If that fails, the sound quality might deteriorate due to buffers working overtime and when these fail, dropouts will occur. Since your neighbours might not use Wi-Fi constantly, the available bandwidth and thus the reliability of the Wi-Fi connection will vary. Luckily, developments in Wi-Fi offer opportunities. Nowadays two radio frequency bands are available for Wi-Fi, 2.4 and 5 GHz. 2.4 GHz is used traditionally for it has a fairly good reach. 5 GHz has less reach and doesn't travel through walls that well. At first sight that might look as a disadvantage but it's just what we need. For it means that it will work fine within your room while Wi-Fi signals from the neighbours will be weaker. So if your router is at ground floor, you will probably have good reception when using the 5 GHz band. Most routers also offer 2.4 GHz simultaneously and if that covers the rest of your house, that's fine. But if not, using mesh Wi-Fi, it is quite easy to have good and reliable Wi-Fi throughout the house. With mesh Wi-Fi you have two or more access points that talk to each other. I've placed TP-Link M5 mesh Wi-Fi stations in the stairwell on all three floors so they can communicate with each other without getting blocked by the concrete floors. The interior walls are Gibson blocks that do not block Wi-Fi signals that much. This setup gives me 85% signal quality throughout the house. I do have a wide connection to the third floor as well, since there are my NASs and the Roon Rock server that need to serve several clients simultaneously. But for client use like mobile devices, streamers and the like, Wi-Fi is sufficient. Another potential problem with Wi-Fi signals is interference from the radio signal used by Wi-Fi. Having a Wi-Fi access point a few meters away from your stereo is one thing. Having a streamer as part of your stereo communicating with your Wi-Fi access point and thus radiating radio waves is something else. Fortunately current audio equipment and most other equipment by the way is built so it has become insensitive to radio waves. I believe it's even part of the CE certification needed to sell equipment in the European Union and I'm sure equal laws will be in place in other markets. That doesn't mean there is no equipment around that is sensitive to radio waves from Wi-Fi or cell phones by the way. All the equipment, especially highly tweaked audio gear, sometimes is and of course poorly designed equipment will always be around. Over the last year audiophile switches have proven that UTP networks cause potential sound quality problems. I'm not going to repeat the problems here in depth but in short the problem lies in pollution of the ground plane of the DAC. Current point of view is that phase noise in the digital signal and leakage current from power supplies are the culprits. Just providing a galvanic separation isn't sufficient if your goal is high sound quality. Network specialists that claim that networks will be lossless are only right as long as the signal is in the digital domain. But when the digital to analogue conversion has to be done, these pollutions will cause jitter. Even the smallest amount of jitter can be audible depending on the spectral content of the jitter. Especially if the jitter contains low frequency components, say below 20 Hz. The bad news is that for instance transformers won't stop this. Re-clocking a signal won't completely solve it either. On the other hand, using UTP cable sufficient bandwidth is always guaranteed, provided your home mates don't use it all. Since glass fiber doesn't conduct electricity, there is no chance leakage from power supplies earlier in the chain pollutes the ground plane of the DAC. But here again, phase noise is simply passed on. Furthermore the network signal has to be converted to optical and back, which again might introduce additional phase noise. The SFB fiber transceiver needed to convert the optical signal back to unshielded twisted pan network cable again might add phase noise while its power supply might leak. At this point you might think that streaming never is going to sound good. I can assure you that only a limited number of CD players will sound equally good as my digital front end in setup 1, especially for about the same money. And there is no point in working hard on the front end if the amplifier and speakers are low-fi. A €1000 switch for a €600 stereo is giving very low return on investment, if any. For a 20K costing stereo it does give a high return, provided it is properly selected and set up. It is always important to follow the signal part and start investing closest to the source. If signal quality is lost upfront, you will never get it back. Make sure you use quality power supplies through any piece of gear that is connected directly or indirectly to your stereo. What power supply is the best depends on the gear you use but if you want or need a switch mode power supply, find one of medical great quality. Quality switch mode power supplies might be a better choice for digital gear that demands higher instant currents. They are capable of delivering current instantly. Linear power supplies are generally a better choice for less current hungry equipment and equipment that also contain analog electronics, like DACs and streamers with integrated DACs. But be careful with shielded twisted pair network cables since the shielding is a means of transport for voltage leakage. Let's kick in an open door. Quality pays. If you don't care too much about audio quality, this video is hardly interesting for you. I know I could have said that earlier. If sound quality does have a priority, there are two ways to go. Have an expert dealer help you or do it yourself. If you do it yourself, work systematically, again working from the source towards the loudspeakers. Try to avoid stacked solutions like a reclocker and a transformer inline in a signal path unless you are certain it leads to improvements. This not only goes for Ethernet connections, but for all digital connections. It is by the way cheaper in the end to start with quality equipment than to try to upgrade cheap equipment with problem solvers. It was my intention to end this video with my listening experiences, but Covid-19 interfered with that. I will pick that up later when we have it behind us. And talking of Covid-19, please be very, very careful. Stay at home if you can. It's worse enough that there are those that need to be working to keep us safe and nourished. Keep a distance when shopping, in both your interest and that of the supermarket staff, for it's a very aggressive virus. The famous late soccer player Johan Krav once said that every disadvantage has its advantage. If you stay at home, there is more time to enjoy the music. Please be careful.