Streaming from a NAS in RAID 6

To answer the question you asked - If you get a decent quality system, and most RAID 6 systems are enterprise quality, you shouldn't have any issues.

Please take this in the spirit of saving you lots of time and money, not as a put down: Your saying "I'm pretty new to this" begs me to add that there is absolutely no reason you need RAID 6 for personal backup and music streaming.  If you are really  paranoid, as I am  myself,  I'd recommend a high quality 1 bay NAS + automated online backup from one of the many providers out there. Then, relax and enjoy your music. 

RAID 6 is designed for 2 simultaneous drive failures. https://en.wikipedia.org/wiki/Standard_RAID_levels

RAID 6 doesn't necessarily give you "more secure" backup.  Rather, it is designed to avoid downtime for a storage system that needs to be continuously available.  In other words, someone gets fired if its not working.

The chances of your house burning down, or - more likely - your fiddling with the RAID controller and spending hours getting it back up again - are way higher than 2 simultaneous drive failures.

Also remember to have an external back up to the NAS RAID.  Even if it's only updated once a month - either physical or cloud ( just make sure you have band width/space on your internet plan )

One other setup piece is that you are connecting the NAS to a switch and the switch is connected to PC / Amp / Internet Router et al.  This will also the best access to the files.

Remember the higher up the RAID chain you go, the less 'useable' space you will have in your NAS.  i.e Four 3TB drives (in 'Just a Bunch of Disks' ) when formatted give 11TB of space (from 12TB), in RAID 5 it would go to 8TB and less in RAID 6.  If things were to fail it would take a few days to re build the disk array too. 

You need to calculate how much music and photos et al you have and how much you are adding to the drives on an annual rate, to give an idea of the space you will need and how soon you will use up the remaining space.. as that will help you determine the type of device/space you need.

Thanks everyone for your replies. I need to think long and hard over why I want a NAS and what my backup strategy needs to be.

The most vulnerable part of multi-bay NAS is the bay itself. I had the misfortune of a controller of a NAS fail and I could not have done any better if I had taken a sledgehammer to it. As the principle of RAID is to spread the data over the multiple disks and use algorithms to recreate a failed unit, if the controller loses the algorithmic 'thread' then the whole lot becomes mush. 

Wow! I didn't realise a multi-bay NAS could be so vulnerable. Maybe a good idea would be a 2 bay NAS in RAID1 mirroring (with big 3TB discs) and an online backup.

This has happened to me once. I now have a lot of stuff on NAS in a Just a Bunch Of Disks  array with backups and backups of the backups. I have another NAS running a RAID but have double backups also. Storage is cheap and external USB HDDs are a doddle to use.

Multibay is not as bad as you seem to have assumed, if it was as bad I would wonder why so many business users are able to survive. But yes I agree you are on the right track for home use with a simple 2 bay & a simple back up like USB is really all you need.   

I'm streaming from a 4-bay NAS configured in raid-6 after I had two almost simultaneous hd failures whilst it was configured in raid-5...

I had a backup of the NAS, but it's a tedious job to restore it - I had thought you could leave the backup drive plugged into the NAS to restore, but no, you have to plug the backup in somewhere else and copy everything across.