I am utterly confused by reading all this now.
Can someone help me out?
Im planing on building my own plex server, as lowest budget possible and this My Cloud Expert Series EX2 Ultra plex, seems more than welcome.
My requirements are, running mkv files as big as 15-30GB on full 1080p (maybe upscale 4k at all??) and at lest 2-3 simultaneous streams?
As players i mostly use a mini voyo v2 pc and some smart tv’s with their dedicated plex app, so this NAS wont be needed to act as a playing streaming device, just as server.
Is it doable?
Thanks in advance
Hi @FlameCRO
first of all, welcome to the WD section of the Plex community.
Your requirements are direct bound to your players. If your players and Smart TVs are capable of playing MKV, then your major “problem” is solved. Best practise is to have the Plex client installed on these players which then supports co called DirectPlay. DirectPlay will not cause any transcoding but simply plays the content “as is”.
Within your requirements, wou wrote about upscaling to 4K. This is a feature which will be done by the TV, not by Plex. It’s working well on my 4K-TVs, so I don’t expect problems on other 4K TVs.
Remind that MKV is not a codec but a container. Inside any MKV, there is at least the encoded video stream and the encoded audio stream. So your player has to support the codecs that are in the MKV, for example H.264 or H.265 for video and some audio codecs. If your player does not support these codecs natively, you will get an error like “video codec not supported” or “unknown audio codec” from your player and Plex may offer transcoding - which will (not may) cause problems if your CPU is to weak to do this on the fly (EX2 Ultra’s CPU is ARM which is too weak, My CLoud PR2100 is Intel Quad-Core with GPU and powerfull enough for transcoding but a bit more costly than My Cloud EX2 Ultra). If you know that your players can support your codecs in use, you will not run into any problem with My Cloud EX2 Ultra.
File sizes of several dozen Gigabyte are no matter as these files will be streamed, not copied. Even several streams (you wrote 2-3 simultaneously) are no issue as the bandwidth needs per stream are very low in a cabled network. If you are on Wifi network with only one access point, several streams may be not possibile due to the bandwidth limitations of Wifi. If you have cabled connection, there are no bandwidth issues.
If you respect this, you will have a lot of fun 
best regards,
Jörg
Thanks @JoergAndreas
Well described, just what I was looking for.
But, some things are still a little bit confusing. So basically, I inside my network, no matter how many devices who are able to play the appropriate file systems such as mkv, will have no problems streaming or what so ever as long as the cables can deal with the bandwith,right? What about those who are not inside my network, but 2 blocks away, but a registered inside my plex list so he can enjoy the stuff, will he be able to stream the stuff off “my” cloud ex2 ultra?
One more thing buggs me, why do people keep saying the more powerful cpu and ram of the media server is, the more it can handle…but handle what?
Thanks
“Fasten your seatbelt”, I’ll try to explain…
no matter how many devices who are able to play the appropriate file systems such as mkv
Appropriate CODEC, not file system nor file ending 
A File System is what the NAS uses internally to store files. Your player or TV will not recognize this anyway.
You refer to file types or so called codecs. These are MP3, AAC, FLAC, H.264, H.265 etc. AVI and MKV are containers which have encoded files (or streams) inside. Supporting MKV does NOT mean that the inner codec will be supported too! Example: if your player states to support MKV (as file type) but not H.264 (as codec) you are lost and see an error message with “unsupported video codec”. A codec is a method to encode video and/or audio and pack both into a file. The player then is able to decode it back into video and audio which you then see and hear. There are standard codecs with huge base of supported players, but there are special codecs or proprietary codecs that can cause huge trouble.
will have no problems streaming or what so ever as long as the cables can deal with the bandwith,right?
Correct; as long as you are on cabled network, nothing will happen regarding bandwidth problems
What about those who are not inside my network, but 2 blocks away, but a registered inside my plex list so he can enjoy the stuff, will he be able to stream the stuff off “my” cloud ex2 ultra?
Think about this question again Where is the bandwidth limiter hidden? It’s your origin UPLOAD speed to the internet which limits the bandwidth. So, if you have 1 MBit/s upload speed into the Internet, you cannot stream above this level - I expect your can stream up to 50% net throughput, so if you have 1 MBit/s upload, you may end up in 500 KBit/s streaming bandwidth out off your own network into the internet. It does not matter if an external player is registered at your internal Plex; your external line is the limiter. So you - or better spoken your guest - will receive very limited streaming bandwidth; due to your upload speed.
why do people keep saying the more powerful cpu and ram of the media server is, the more it can handle
Because a lot of people out there are not familiar with the specialties of media streaming and network technology 
I am with media streaming now since more than 10 years, started somewhere in 2005 with the first media streaming device, introduced Buffalo LinkTheater with corresponding Media Server on the first NAS device (a monstruous NAS called TeraStation HD-HTGL with 4 x 160GB PATA drives inside and a 266 MHz PowerPC CPU). Even this NAS was able to stream a never-seen-before video recorded in Full-HD during German CeBIT in 2006. I used a very special monitor of Video7 which was the first Full-HD panel in the market, in the year 2006. Since these times, not that much as changed. It’s still a question of what the player is capable, not the server. If the player is OK, the server has no issues. If the player cannot support what you want, the server mostly is lost if you saved money on the wrong side (more below…)
It’s always the same thing: the capabilities of the media player limits what can be played. If the TV is not able to handle the stuff, you end up in a nightmare. Plex Client (Original Plex as App or OpenPHT) solves a lot of issues as this Plex Client can handle things different to a normal media server/client team. if you are using a dlna-certified player/server team, then the client sends a profile to the server where all the stuff in listed, what the client does support. Based on this profile, the clients gets from the server what the client is able to consume. Other way round, if the client does not support something, it will not be available. Or causes problems if the profile content is wrong.
Plex is different. Plex can rework original stuff into other formats which then can be used by the player device. This is called transcoding. A lot of people out there does not understand what transcoding means in reality. It means that the Server has to rework video and audio simultaneously from one format into another format and then sends this reworked stuff out. This means technically, that you need an extremely powerfull machine to serve this feature. Most CPUs in NAS are not made for this job, even a mid-range PC can run into problems with these jobs. See it like a professional “simultaneous interpreter” or " simultaneous translator", the job is to listen carefully to a speaker and translate everything on-the-fly into another language; you can imagine how hard this is. It’s the same for transcoding where the server has to render each frame into a different format but also has to take care that the fitting sound will not be messed up too.
At the end of the story (sorry for this long story): take care that your content fits to what your player support and you will not run into an issue.
But if you think that your player has to do things that the player never ever would support from scratch, then you may end up in the “my CPU is not powerfull enough” nirvana of this forum Subtitles are a very nice example for this capability-nirvana.
best regards;
Jörg
@JoergAndreas said:
But if you think that your player has to do things that the player never ever would support from scratch, then you may end up in the “my CPU is not powerfull enough” nirvana of this forum
Or, you just buy a server powerful enough for your needs, and you don’t have to care anymore about the client supported sites. I mean, this is the most interesting feature of Plex. I changed a couple of “media players with hard drive” when they started not supporting the formats I was throwing at them, but now with Plex I don’t care much about the client anymore: I know everything will play, because Plex will take care of current and future formats I might want to use 
Of course this is easy if you are a single user/single streamer, much more difficult if external users or remote access is taken into the equation
I think i finally have all the answers to the questions that have been bothering me.
The biggest question mark above my head was with the word “transcoding”, in short,so as long as I keep the “original” state of the movie, and i mean in the playback option theres a setting with Original to lower qualities, without the NAS ex2 ultra having to transcode to any lower quality, I am good, its all about transcoding (keep in mind all my players/TV’s can run all the correct codecs without any problems). Is that correct?
CPU and RAM are required only if transcoding is needed (plex decreasing the quality or adjusting to correct codec for player to be able to play), am I finally right? 
My voyo v2 is a mini pc with windows 10, and ive been using as a plex media server on my regular desktop PC for a few months now and voyo handled all without any problems, nor any hickups and such. So apparently its good for my plex content as it runs smoothly
@FlameCRO said:
I think i finally have all the answers to the questions that have been bothering me.
The biggest question mark above my head was with the word “transcoding”, in short,so as long as I keep the “original” state of the movie, and i mean in the playback option theres a setting with Original to lower qualities, without the NAS ex2 ultra having to transcode to any lower quality, I am good, its all about transcoding (keep in mind all my players/TV’s can run all the correct codecs without any problems). Is that correct?
CPU and RAM are required only if transcoding is needed (plex decreasing the quality or adjusting to correct codec for player to be able to play), am I finally right?
Your assumptions are all correct
Woohoo, finally.
I will be buying ex2 later today then.
Buuut, is it even capable of any transcoding at all?
Just out of curiosity…
Thank you @JoergAndreas, thank you for your time you spent on trying to explain 
, it really helped a lot!
I have been using an EX2 Ultra for Plex streaming. Works very well. I have no need for trans-coding so the EX2 Ultra does the job. I use it to stream to an ATV4, Roku, Samsung tv and iPads and no problems at all. The Plex server app for WD gets regular updates and these are easy to install. I’ve been happy with this purchase.
What are the best formats and sizes of videos for direct play / direct stream?
